Patent Publication Number: US-11659894-B2

Title: Sole system for an article of footwear incorporating a knitted component

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/847,533, filed Dec. 19, 2017, which is a continuation of U.S. patent application Ser. No. 14/598,389, filed Jan. 16, 2015. All applications listed in this paragraph are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND 
     The present disclosure relates generally to a vacuum formed knit sole system for an article of footwear incorporating a knitted component. The present disclosure also relates to an article of footwear comprising the knitted component forming the knit sole system. The present disclosure further is related generally to a method of vacuum forming the knitted component using an insert member to form the knit sole system. 
     Conventional articles of footwear generally include two primary elements, an upper and a sole structure. The upper is secured to the sole structure and forms a void on the interior of the footwear for comfortably and securely receiving a foot. The sole structure is secured to a lower area of the upper, thereby being positioned between the upper and the ground. In athletic footwear, for example, the sole structure may include a midsole and an outsole. The midsole often includes a polymer foam material that attenuates ground reaction forces to lessen stresses upon the foot and leg during walking, running, and other ambulatory activities. Additionally, the midsole may include fluid-filled chambers, plates, moderators, or other elements that further attenuate forces, enhance stability, or influence the motions of the foot. 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 sole structure may also include a sockliner positioned within the void and proximal a lower surface of the foot to enhance footwear comfort. 
     The upper generally extends over the instep and toe areas of the foot, along the medial and lateral sides of the foot, under the foot, and around the heel area of the foot. In some articles of footwear, such as basketball footwear and boots, the upper may extend upward and around the ankle to provide support or protection for the ankle. Access to the void on the interior of the upper is generally provided by an ankle opening in a heel region of the footwear. A lacing system is often incorporated into the upper to adjust the fit of the upper, thereby permitting entry and removal of the foot from the void within the upper. The lacing system also permits the wearer to modify certain dimensions of the upper, particularly girth, to accommodate feet with varying dimensions. In addition, the upper may include a tongue that extends under the lacing system to enhance adjustability of the footwear, and the upper may incorporate a heel counter to limit movement of the heel. 
     Articles of footwear often are constructed of many components. For example, an article of footwear may include many components, such as an upper, a sockliner, a strobel, a midsole, and an outsole. An outsole may have spikes, cleats, or other protrusions to provide additional traction under selected circumstances. Each of these components is attached to at least one, typically two, and maybe three or more of the other components. Some components thus are stitched to, adhered to, or otherwise attached to other components. 
     Construction of an article of footwear comprising many components may require that components having significantly different properties and characteristics must be attached to each other. For example, an upper may be formed from cloth, a midsole from soft foam, and an outsole from wear-resistant rubber. These components often can be adhered with adhesives. Adhesive may fail, causing delamination of the components. Further, wear may occur at joints between harder and softer materials, or between dissimilar materials. Therefore, such joints may cause premature failure of the article of footwear. Such joints also may provide uncomfortable sudden transitions between areas of softer or more compliant materials and areas of harder or more rigid materials. 
     Further, assembly of multiple components may be time-consuming and may lead to errors. For example, components from one style of an article of footwear may incorrectly be used on a different style of footwear. The number of potential errors and premature failures may be significant. 
     A variety of material elements (e.g., textiles, polymer foam, polymer sheets, leather, synthetic leather) are conventionally utilized in manufacturing an article of footwear. In athletic footwear, for example, the upper may have multiple layers that each include a variety of joined material elements. As examples, the material elements may be selected to impart stretch-resistance, wear-resistance, flexibility, air-permeability, compressibility, comfort, and moisture-wicking to different areas of the upper. Similarly, the sole structure may utilize a number of components to provide selected properties and characteristics. To impart the different properties to different areas of the article of footwear, material elements are often cut to desired shapes and then joined together, usually with stitching or adhesive bonding. Moreover, the material elements often are joined in a layered configuration to impart multiple properties to the same areas. As the number and type of material elements incorporated into the article of footwear increases, the time and expense associated with transporting, stocking, cutting, and joining the material elements also may increase. Waste material from cutting and stitching processes also accumulates to a greater degree as the number and type of material elements incorporated into the article of footwear increases. Moreover, articles of footwear with a greater number of material elements may be more difficult to recycle than articles of footwear formed from fewer types and numbers of material elements. By decreasing the number of material elements utilized in the article of footwear, therefore, waste may be decreased while increasing the manufacturing efficiency and recyclability of the upper. 
     Reducing the number of material elements may require that one material element provide multiple and additional properties and characteristics sought by users. Thus, there exists a need in the art for articles of footwear comprising a minimum number of material elements while providing a number of properties and characteristics sought by users. 
     SUMMARY 
     In one aspect, the invention provides an article of footwear including an upper and a sole system. The article of footwear comprises a knitted component formed of unitary knit construction, the knitted component including a knitted component lower portion forming a knit outsole of the sole system and a knitted component upper portion forming at least a portion the upper. An insert member can be disposed within an interior of the upper. The insert member having a plurality of protuberances extending away from a bottom side. The plurality of protuberances extending away from the bottom side of the insert member correspond with a plurality of cleat members extending away from an outsole bottom surface of the knit outsole. 
     In another aspect, the invention provides a method of manufacturing an article of footwear including an upper and a sole system incorporating a knitted component. The method includes knitting a knitted component upper portion and a knitted component lower portion of unitary knit construction so as to be a one-piece element. The method also includes providing an insert member having a plurality of protuberances on one side of the insert member and vacuum forming the knitted component lower portion around the insert member to form a knit outsole having a plurality of cleat members corresponding to the plurality of protuberances on the one side of the insert member. The method further includes incorporating the knitted component upper portion into at least a portion of the upper of the article of footwear. 
     Other systems, methods, features and advantages of the invention will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the invention, and be protected by the following claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views. 
         FIG.  1    is an isometric view of an exemplary embodiment of an article of footwear including a knit sole system; 
         FIG.  2    is a lateral side view of the exemplary embodiment of an article of footwear including a knit sole system; 
         FIG.  3    is a medial side view of the exemplary embodiment of an article of footwear including a knit sole system; 
         FIG.  4    is an underside view of the exemplary embodiment of an article of footwear including a knit sole system; 
         FIG.  5    is an exploded view of the exemplary embodiment of an article of footwear including a knit sole system with an insert member; 
         FIG.  6    is a schematic view of the exemplary embodiment of an article of footwear upper shown in phantom with an insert member disposed within the knit sole system; 
         FIG.  7    is a cross-sectional view of the exemplary embodiment of an article of footwear including a knit sole system with an insert member; 
         FIG.  8    is a schematic flowchart of an exemplary process for manufacturing an article of footwear including a knit sole system; 
         FIG.  9    is a representational view of an exemplary process of vacuum forming a knit sole system for an article of footwear incorporating a knitted component; 
         FIG.  10    is a representational view of a vacuum press for vacuum forming a knit sole system; 
         FIG.  11    is a representational view of a vacuum press including a last with an insert member for vacuum forming a knit sole system; 
         FIG.  12    is a representational view of a vacuum press having a knitted component being placed over the last for vacuum forming a knit sole system; 
         FIG.  13    is a representational view of a knitted component disposed in a last in a vacuum press for vacuum forming a knit sole system; 
         FIG.  14    is a representational view of a vacuum press closing over a last having the knitted component for vacuum forming a knit sole system; 
         FIG.  15    is a representational view of a closed vacuum press for vacuum forming a knit sole system; 
         FIG.  16    is a representational view of a vacuum press applying vacuum pressure to a knitted component for vacuum forming a knit sole system; 
         FIG.  17    is a representational view of a vacuum press being removed from a vacuum formed knit sole system; 
         FIG.  18    is an exploded view of an exemplary embodiment of cap elements disposed on cleat members of a knit sole system; 
         FIG.  19    is a cross-sectional view of an exemplary embodiment of an article of footwear including a knit sole system with cap elements on cleat members; 
         FIG.  20    is a cross-sectional view of an alternate embodiment of a cap element for a cleat member of a knit sole system; 
         FIG.  21    is a cross-sectional view of another alternate embodiment of a cap element for a cleat member of a knit sole system; 
         FIG.  22    is a cross-sectional view of another alternate embodiment of a cap element for a cleat member of a knit sole system; 
         FIG.  23    is a cross-sectional view of another alternate embodiment of a cap element with a tiered arrangement for a cleat member of a knit sole system; 
         FIG.  24    is an exploded view of an exemplary embodiment of an outsole cover assembly for a knit sole system of an article of footwear; 
         FIG.  25    is an isometric view of the exemplary embodiment of an outsole cover assembly for a knit sole system of an article of footwear; and 
         FIG.  26    is a cross-sectional view of the exemplary embodiment of an outsole cover assembly for a knit sole system of an article of footwear taken along line  26 - 26  in  FIG.  25   . 
     
    
    
     DETAILED DESCRIPTION 
     The following discussion and accompanying Figures disclose a variety of concepts relating to knitted components and the manufacture of knitted components. Although the knitted components may be utilized in a variety of products, an article of footwear that incorporates one of the knitted components is disclosed below as an example. The description will be directed in detail to an article of footwear. However, in addition to footwear, the knitted components may be utilized in other types of apparel (e.g., gloves or mittens) where the ability to securely grip an object may be enhanced by protuberances. Accordingly, the knitted components and other concepts disclosed herein may be incorporated into a variety of products for both personal and industrial purposes. 
       FIGS.  1  through  26    illustrate exemplary embodiments of an article of footwear having an upper and a knit sole system incorporating a knitted component and the associated method of manufacturing. The upper and knit sole system incorporate a knitted component that is vacuum-formed to produce a knit outsole having cleat members. The individual features of any of the knitted components described herein may be used in combination or may be provided separately in different configurations for articles of footwear. In addition, any of the features may be optional and may not be included in any one particular embodiment of a knitted component. 
     For consistency and convenience, directional adjectives are employed throughout this detailed description corresponding to the illustrated embodiments. The term “longitudinal” as used throughout this detailed description and in the claims refers to a direction extending a length or major axis of an article. In some cases, the longitudinal direction may extend from a forefoot region to a heel region of the article. Also, the term “lateral” as used throughout this detailed description and in the claims refers to a direction extending a width or minor axis of an article. In other words, the lateral direction may extend between a medial side and a lateral side of an article. Furthermore, the term “vertical” as used throughout this detailed description and in the claims refers to a direction generally perpendicular to a lateral and longitudinal direction. For example, in cases where an article is planted flat on a ground surface, the vertical direction may extend from the ground surface upward. It will be understood that each of these directional adjectives may be applied to individual components of an article, including an upper, a knitted component and portions thereof, and/or a sole system. 
       FIGS.  1  through  7    illustrate an exemplary embodiment of an article of footwear  100 , also referred to simply as article  100 . In some embodiments, article of footwear  100  may include a sole system  110  and an upper  120 . Although article  100  is illustrated as having a general configuration suitable for enhanced traction, concepts associated with article  100  may also be applied to a variety of athletic footwear types, including soccer shoes, baseball shoes, basketball shoes, cycling shoes, football shoes, tennis shoes, training shoes, walking shoes, and hiking boots, for example. The concepts may also be applied to footwear types that are generally considered to be non-athletic, including dress shoes, loafers, sandals, and work boots. Accordingly, the concepts disclosed with respect to article  100  may be applied to a wide variety of footwear types. 
     For reference purposes, article  100  may be divided into three general regions: a forefoot region  101 , a midfoot region  102 , and a heel region  103 . Forefoot region  101  generally includes portions of article  100  corresponding with the toes and the joints connecting the metatarsals with the phalanges. Midfoot region  102  generally includes portions of article  100  corresponding with an arch area of the foot. Heel region  103  generally corresponds with rear portions of the foot, including the calcaneus bone. Article  100  also includes a lateral side  104  and a medial side  105 , which extend through each of forefoot region  101 , midfoot region  102 , and heel region  103  and correspond with opposite sides of article  100 . More particularly, lateral side  104  corresponds with an outside area of the foot (i.e., the surface that faces away from the other foot), and medial side  105  corresponds with an inside area of the foot (i.e., the surface that faces toward the other foot). Forefoot region  101 , midfoot region  102 , heel region  103 , lateral side  104 , and medial side  105  are not intended to demarcate precise areas of article  100 . Rather, forefoot region  101 , midfoot region  102 , heel region  103 , lateral side  104 , and medial side  105  are intended to represent general areas of footwear  100  to aid in the following discussion. In addition to article  100 , forefoot region  101 , midfoot region  102 , heel region  103 , lateral side  104 , and medial side  105  may also be applied to sole system  110 , upper  120 , and individual elements thereof. 
     In some embodiments, article  100  may include sole system  110  and upper  120  that are formed from portions of a knitted component incorporated into article  100 . The sole system  110  and upper  120  may be formed of unitary knit construction from a knitted component so as to form a one-piece element that includes sole system  110  and upper  120 . A portion of the knitted component may form a knit outsole of sole system  110  and another portion of the knitted component may form the majority of upper  120 . 
     In some embodiments, sole system  110  is secured to upper  120  and extends between the foot and the ground when article  100  is worn. In an exemplary embodiment, the primary element of sole system  110  is a knitted component lower portion  111  that forms a knit outsole  112  through a vacuum forming process, as further detailed below. Knit outsole  112  includes an outsole top surface or side  113  (see  FIG.  5   ), an outsole bottom surface or side  114 . In some embodiments, sole system  110  may include one or more protuberances or projections that may assist with providing traction to article  100 . In one embodiment, knit outsole  112  includes a plurality of ground-engaging cleat members  115  that extend outward from outsole bottom surface  114  in the vertical direction towards a ground surface. 
     Knitted component lower portion  111  forming knit outsole  112  is of unitary knit construction with the lower areas of upper  120 . In one embodiment, knit outsole  112  and upper  120  may be formed from different portions of a single one-piece knitted component. Outsole top surface or side  113  is located on the top surface of knit outsole  112 , and is positioned to extend under a lower surface of the foot. Outsole bottom surface or side  114  comprises the outer bottom ground-facing surface of sole system  110  and the bottom surface of article of footwear  100 . Referring now to  FIG.  4   , outsole bottom surface or side  114  faces away from the foot, and may be ground-engaging if, for example, ground-engaging cleat member  115  becomes embedded in the ground. Ground-engaging cleat members  115  protrude from outsole bottom surface  114  and include a cleat face  116  at a distal end that is oriented approximately parallel to outsole bottom surface  114 . In one embodiment cleat face  116  may be a knit surface of a portion of knitted component lower portion  111  that has been vacuum formed to produce cleat members  115 . 
     With this configuration, cleat face  116  of ground-engaging cleat member  115  engages the ground first. Although this configuration for sole system  110  provides an example of a sole system that may be used in connection with upper  120 , a variety of other conventional or nonconventional configurations for sole system  110  may also be used. Accordingly, the features of sole system  110  or any sole system utilized with upper  120  may vary considerably. 
     Upper  120  defines a void within article  100  for receiving and securing a foot relative to sole system  110 . The void is shaped to accommodate the foot and extends along a lateral side of the foot, along a medial side of the foot, over the foot, around the heel, and under the foot. Access to the void is provided by an ankle opening  121  located in at least heel region  103 . In further configurations, upper  120  may include additional elements, such as (a) a heel counter in heel region  103  that enhances stability, (b) a toe guard in forefoot region  101  that is formed of a wear-resistant material, (c) a collar extending around ankle opening  121 , and (d) logos, trademarks, and placards with care instructions and material information. 
     Many conventional footwear uppers are formed from multiple material elements (e.g., textiles, polymer foam, polymer sheets, leather, and synthetic leather) that are joined through stitching or bonding, for example. In contrast, in embodiments of the disclosure, a majority of upper  120  may be formed from a knitted component upper portion  130 , which extends through each of forefoot region  101 , midfoot region  102 , and heel region  103  along both lateral side  104  (shown in  FIG.  3   ) and medial side  105  (shown in  FIG.  2   ), over forefoot region  101 , and around heel region  103 . In addition, knitted component upper portion  130  forms portions of both an exterior surface and an opposite interior surface of upper  120 . As such, knitted component upper portion  130  defines at least a portion of the void within upper  120 . 
     In some embodiments, article of footwear  100  may be formed from a one-piece knitted component that includes knitted component lower portion  111 , forming knit outsole  112  of sole system  110 , and knitted component upper portion  130 , forming the majority of upper  120 . Thus, the upper and the outsole may comprise a textile knitted together as a one-piece knit element. Forming an article of footwear as a one piece knit textile element through knitting provides significant advantages over typical articles of footwear. For example, there is no need to attach a separate outsole to an upper, thus significantly reducing the number of steps required for assembly and, therefore, the possibility of assembly errors. Also, there are no joints between the outsole and the upper at which disparate properties and characteristics of the joined materials may cause excessive wear and premature failure. 
     In some embodiments, upper  120  and sole system  110  are formed by a single knitted component, including knitted component lower portion  111  and knitted component upper portion  130 .  FIG.  1    through  FIG.  7    illustrate such an embodiment, wherein upper  120  and sole system  110  comprise a single knitted component. In these embodiments, knitted component upper portion  130  and knitted component lower portion  111  of sole system  110  are formed of unitary knit construction so as to be a one-piece knit element. Boundary  117  depicts an area of demarcation between upper  120  and sole system  110 . However, for embodiments of article  100  including upper  120  and sole system  110  formed from a single knitted component that encloses the foot and includes knit outsole  112 , boundary  117  may not be actually physically present or visible on article  100 . That is, boundary  117  may represent an imaginary dividing line between the portions of the single knitted component that form each of upper  120  and sole system  110  and no indicia corresponding to boundary  117  may be present. In other embodiments, boundary  117  may represent a transition between types of yarns used to form each of knitted component lower portion  111  and knitted component upper portion  130 . 
     In various embodiments, the single knitted component incorporating into article  100 , including each of knitted component lower portion  111  and knitted component upper portion  130 , may incorporate various types of yarn that impart different properties to separate areas of upper  120  and/or sole system  110 . For example, one area or portion of knitted component upper portion  130  may be formed from a first type of yarn that imparts a first set of properties, and another area or portion of first knitted component upper portion  130  may be formed from a second type of yarn that imparts a second set of properties. In this configuration, properties may vary throughout upper  120  by selecting specific yarns for different areas of knitted component  130 . Similarly, knitted component lower portion  111  of sole system  110  may be knitted from various yarns, including any of the yarns used to form knitted component upper portion  130 . With this configuration, different yarns may be used to impart different properties to each of knitted component lower portion  111  and knitted component upper portion  130 , as well as to different areas within each of knitted component lower portion  111  and knitted component upper portion  130 . 
     Yarns used in embodiments of the disclosure may be selected from monofilament yarns and multifilament yarns formed from natural or synthetic materials. Multifilament yarns may be twisted or untwisted. In some embodiments, yarn may be elastic or essentially inelastic. In some embodiments, yarn may be textured or have a natural finish. Natural materials may be selected from staple materials, such as silk, cotton, and wool. Synthetic materials may be selected from polymers that can be formed into filaments. Synthetic materials include but are not limited to polyesters; polyamides, such as any of the various types of homopolymeric and co-polymeric nylon; aramides, such as Kevlar® KEVLAR® and Nomex® NOMEX®; and urethanes, such as thermoplastic polyurethane. Fusible yarns also may be suitable for some embodiments. 
     In embodiments of the disclosure, the yarn used to form the article of footwear may incorporate yarns with different deniers, materials (e.g., cotton, elastane, polyester, rayon, wool, and nylon), and degrees of twist, for example. The different types of yarns may affect the physical properties of a knitted component, including aesthetics, stretch, thickness, air permeability, and abrasion-resistance. In some configurations, multiple yarns with different colors may be utilized to form the knitted component. When yarns with different colors are twisted together and then knitted, the knitted component may have a heathered appearance with multiple colors randomly distributed throughout. 
     In some embodiments, sole system  110  may be provided with additional components configured to provide support and stability to knit outsole  112 . In an exemplary embodiment, sole system  110  may include an insert member  300  that is configured to be placed in relationship with knit outsole  112  from an interior of article  100 . Insert member  300  may fill and provide structural support and/or rigidity for cleat members  115 . 
       FIG.  5    illustrates an exemplary embodiment of insert member  300  shown in an exploded view positioned above article  100 . Insert member  300  may be placed in relationship with knit outsole  112  to form sole system  110 . Insert member  300  is disposed below a foot of wearer when placed within article  100  and includes a top side  302  that faces towards the foot and an opposite bottom side  304  that faces away from the foot. In some embodiments, knit outsole  112  includes a plurality of cavities  200  in outsole top surface  113  that correspond with and form cleat members  115 . In this embodiment, cavities  200  forming cleat members  115  in knit outsole  112  may be hollow. 
     In an exemplary embodiment, insert member  300  may further include a plurality of protuberances  310  that extend away from bottom side  304 in a vertical direction. Protuberances  310  may be configured and designed so as to correspond with and fit within cavities  200  of knit outsole  112  to reinforce and provide support and/or rigidity to cleat members  115 . In one embodiment, the location, size, and arrangement of protuberances  310  on insert member  300  may be substantially similar and correspond with the location, size, and arrangement of cavities  200  on outsole top surface  113  forming cleat members  115 . For example, in exemplary embodiments, an article of footwear may include between 5 and 15 protuberances  310  that are associated with between 5 and 15 cleat members  115  (such as 11 protuberances  310  and 11 cleat members  115  as depicted in  FIG.  5   ). With this arrangement, protuberances  310  on bottom side  304  are aligned with cavities  200  on outsole top surface  113  so that when insert member  300  is placed in relationship with knit outsole  112  within the interior of article  100 , protuberances  310  substantially fill cavities  200  and provide reinforcement to cleat members  115 . Additionally, insert member  300  may have an outer peripheral edge defining a shape of insert member  300  that is configured and designed to fit within the interior of upper  120  of article  100 . 
     Referring now to  FIG.  6   , insert member  300  having protuberances  310  extending from bottom side  304  is shown in relationship with knit outsole  112 . In this embodiment, knitted component upper portion  130  and knitted component lower portion  111  are shown in phantom view to illustrate the relationship of insert member  300  within knit outsole  112 . As seen in  FIG.  6   , when insert member  300  is located within the interior of upper  120  of article  100  so that bottom side  304  is facing outsole top surface  113 , protuberances  310  are aligned with and fill cavities  200  of corresponding cleat members  115 . 
     In some embodiments, insert member  300  is placed or affixed to outsole top surface  113  of knit outsole  112 . A cross-sectional view shown in  FIG.  7   , illustrates insert member  300  in place on outsole top surface  113  of knit outsole  112 . Protuberances  310  are located within and substantially fill cavities  200  to reinforce cleat members  115 . Top side  302  of insert member  300  may be the foot-contacting surface and bottom side  304  faces the opposite direction towards outsole top surface  113 . Outsole bottom surface  114  includes the ground-engaging cleat members  115  that are facing downward in a vertical direction away from outsole bottom surface  114 . Cleat face  116  of cleat members  115  is a knit surface that may be directly in contact with the ground when article  100  is worn. Other surfaces of knit outsole  112 , such as portions of outsole bottom surface  114 , also may be at least partially directly in contact with the ground when article  100  is worn. 
     With this configuration, insert member  300  fills and provides support to cleat members  115 . Insert member  300  is disposed below a foot of a wearer of article  100  and, in some embodiments, may be configured as a midsole element. That is in some embodiments, additional inserts may be provided within the interior of upper  120 , such as an insole element, to provide further cushioning to a foot of a wearer. In other embodiments, insert member  300  may be used within upper  120  without any additional inserts or elements. In this way, insert member  300  can serve as both a reinforcing member for knit outsole  112  and as a cushioning or padding material for a foot of a wearer. 
     In various embodiments, insert member  300  may be formed from a variety of different materials. Materials for forming insert member  300  may include any suitable reinforcing material. Reinforcing materials may include compositions that provide minimal support. Such compositions may be used to tune a cushioning response. More typically, however, a reinforcing material may be selected for its rigidity and strength. The material may be foamed material, such as foamed plastic materials. For example, foamed thermoplastic polyurethane may be suitable. The density of foamed materials may be controlled to tune cushioning response. Higher density may give a more supportive response and better reinforcement of ground-engaging cleat members. 
     In some embodiments, insert member  300  may be monolithic or may have zones that provide additional support or resistance to twisting, for example. For example, in some embodiments, a material having a greater rigidity may be used to form protuberances  310  of insert member  300  and a material having a lesser rigidity may be used to form remaining portions of insert member  300 . In some cases, portions or the entirety of insert member  300  may comprise foamed thermoplastic material. In other cases, one or more portions of insert member  300  may be formed from different materials. For example, in one embodiment, insert member  300  may comprise a zone of low-density foam, a zone of high-density foam, and a zone of unfoamed material. 
     In some embodiments, an insert member disposed within the interior of upper  120  may be used during the manufacturing of an article  100  to form the shape of a knit outsole, including one or more cleat members disposed on the knit outsole.  FIGS.  8  through  17    illustrate an exemplary process of vacuum forming a knitted component using an insert member to form a knit outsole. In an exemplary embodiment, insert member  300  may be used during the manufacturing of article  100  to form the shape of knit outsole  112 , including plurality of cleat members  115  corresponding to the shape of protuberances  310  of insert member  300 . In one embodiment, a vacuum forming process may be used to shape knitted component lower portion  111  around insert member  300  within upper  120  to form knit outsole  112 . 
     Thus, embodiments of the disclosure provide a method of manufacturing an article of footwear with a sole system having a knit outsole. In accordance with the method, a one-piece knitted component is knitted to include a portion that is vacuum formed around an insert member to produce the knit outsole. A ground-engaging cleat member is formed in the ground-facing side of the knit outsole by vacuum forming the portion of the knitted component around the insert member having a protuberance extending away from a bottom side of the insert member. The vacuum formed cleat member may have a ground-engaging face comprising a knitted surface that engages the ground and may provide traction. 
     Referring now to  FIG.  8   , an exemplary process  800  for manufacturing an article of footwear including a knit sole system is illustrated. In one embodiment, process  800  may include one or more steps that may be repeated to form a completed article of footwear with a knit sole system. The order of the steps is exemplary, and in other embodiments, additional or different steps not shown in  FIG.  8    may be included to produce an article of footwear having a knit sole system. In an initial step  802 , a knitted component configured to be incorporated into the upper of the article of footwear is knit. In an exemplary embodiment, the knitted component may be knit in the configuration of a bootie, including an upper portion for extending around and covering over the top of the foot of a wearer, as well as a lower portion for extending underneath the foot of the wearer. With this configuration, the knitted component may be knit as a bootie that is a one-piece element formed of unitary knit construction that encloses the foot of a wearer. 
     In one embodiment, step  802  may include knitting a knitted component, including portions of a knitted component substantially similar to knitted component lower portion  111  and knitted component upper portion  130 , to form a foot-enclosing knit bootie. Although knitting may be performed by hand, the commercial manufacture of knitted components is generally performed by knitting machines. An example of a knitting machine suitable for producing a knitted component includes a knitting machine having a configuration of a V-bed flat knitting machine for purposes of example, but any of the knitted components described herein may be produced on other knitting machines. The disclosure also is described in detail as it relates to knitted textiles formed by weft knitting, but textiles formed by any suitable knitting process, including but not limited to: weft knitting processes, for example, flat knitting operations or circular knitting operations; warp knitting process; or any other knitting process suitable for providing a knitted textile, may be used. In such embodiments, suitable knitting machines, for example, circular knitting machines or warp knitting machines may be used to form a foot-enclosing knit bootie of unitary knit construction at step  802 . 
     Knitted component  111 , knitted component  130 , and other embodiments of foot-enclosing booties can be formed of unitary knit construction. As used herein, the term “unitary knit construction” means that the respective component is formed as a one-piece element through a knitting process. That is, the knitting process substantially forms the various features and structures of unitary knit construction without the need for significant additional manufacturing steps or processes. A unitary knit construction may be used to form a knitted component having structures or elements that include, in the case of weft knitting, one or more courses of yarn or other knit material that are joined such that the structures or elements include at least one course in common (i.e., sharing a common yarn) and/or include courses that are substantially continuous between each of the structures or elements, or that include, in the case of warp knitting, one or more wales of yarn or other knit material that are joined such that the structures or elements include at least one wale in common (i.e., sharing a common yarn) and/or wales that are substantially continuous between each of the structures or elements. With this arrangement, a one-piece element of unitary knit construction is provided. 
     Examples of various configurations of knitted components and methods for forming knitted components with unitary knit construction are disclosed in U.S. Pat. No. 6,931,762 to Dua; U.S. Pat. No. 7,347,011 to Dua, et al.; U.S. Patent Application Publication 2008/0110048 to Dua, et al.; U.S. Patent Application Publication 2010/0154256 to Dua; and U.S. Patent Application Publication 2012/0233882 to Huffa, et al.; each of which is incorporated herein by reference in its entirety. Knitted component lower portion  111 , knitted component upper portion  130 , and other embodiments of foot-enclosing knit booties remain formed of unitary knit construction when other elements, such as logos, trademarks, placards with care instructions or other information, such as material information and size, tensile or structural elements, are added following the knitting procedure. 
     In some embodiments, a knitted component for forming a knit sole system may include areas knit using durable yarns and/or fusible yarns. Durable yarns and/or fusible yarns typically may provide the wear resistance users likely will prefer to have in ground-engaging areas and areas of the knit sole system that are likely to experience greater wear. For example, the outer surface of the knit sole system comprises a knitted textile, but is likely to experience greater wear because the surface faces the ground and is, at least in part, adjacent ground-engaging cleat members that are configured to be in contact with a ground surface. Further, fusible yarns may provide not only excellent wear resistance, but also support for the bottom of the foot when activated. Strands of fusible yarn may, when heated, fuse to form an impermeable mass and may also impart rigidity to the knitted component. 
     In an exemplary embodiment, cleat members  115  formed in knit outsole  112  may incorporate fusible yarns into knitted component lower portion  111  to impart rigidity to knit outsole  112 . Fusible yarns incorporated into a knitted component may further assist with allowing the knit outsole to retain the shape of inert member used during the vacuum forming process  800  to shape the knit outsole. Fusible yarns also may provide a highly water resistant surface that helps keep the interior of the article of footwear free of water that otherwise would enter the article of footwear from the outside. 
     Next, at step  804 , an insert member, including an insert member substantially similar to insert member  300 , described above, may be manufactured. In one embodiment of step  804 , the insert member may include a midsole, however, as noted above, in other embodiments, the insert member may be used with additional elements, for example, an insole element, or may be used alone and take the place of an insole element or other components. During step  804 , the insert member may be manufactured with a plurality of protuberances that will be used to form the various cleat members or traction elements of the knit outsole. 
     After a suitable midsole insert member has been made at step  802  with the desired location, size, and arrangement of protuberances for forming cleat members on the knit outsole, the midsole insert member may be placed inside the foot-enclosing knit bootie. At step  806 , the foot-enclosing knit bootie is vacuum formed around the foot-enclosing knit bootie to shape the knit outsole. 
     In some embodiments, an additional optional step  808  may be included in process  800  to provide protection to ground-engaging surfaces of the formed cleat members of the knit outsole. In this embodiment, step  808  includes a step of applying a cap element to the cleat member. As will be further described below, the cap element may provide protection to the knit surface of the cleat face, including cleat face  116 , that engages the ground surface. The cap element may also be configured to provide enhanced traction to the knit outsole. 
     Referring now to  FIG.  9   , a representational view of step  806  of process  800  of vacuum forming a knit sole system for an article of footwear incorporating a knitted component is illustrated. As shown in this embodiment, knitted component lower portion  111  is vacuum formed around insert member  300  to form knit outsole  112 . In an exemplary embodiment, bottom side  304  of insert member  300  includes protuberances  310  that will be used to form cavities  200  of cleat members  115  on knit outsole  112 . In this embodiment, bottom side  304  of insert member  300  is brought in relation with outsole top surface  113  of knitted component lower portion  111 . 
     Once insert member  300  and knitted component lower portion  111  are brought in relation with each other, a vacuum forming process may be applied to shape knitted component lower portion  111  around bottom side  304  of insert member  300 , including the shape of protuberances  310 . Once vacuum formed, knitted component lower portion  111  forms knit outsole  112 , including cleat members  115  extending from outsole bottom surface  114 . 
     In some embodiments, fusible yarn may be knitted in this area, for example, at least on portions of knitted component  111  aligned with and corresponding to protuberances  310  for forming ground-engaging cleat members  115 . Fusible yarn may be optionally heated at step  806  to soften the outer surfaces of the yarn to assist with conforming to the shape of insert member  300  and protuberances  310 . Upon cooling, fusible yarn may also provide additional rigidity and assist with retaining the shape of cleat member  115 . Alternatively, a stiffening resin or plastic may be applied and activated and cured or heated at step  806  to assist with rigidity and/or shape retention. 
       FIGS.  10  through  17    illustrate various steps of the process of vacuum forming described generally with reference to step  806  of process  800 . In this process, additional or different steps may be performed during the vacuum forming process without detracting from the principles of the exemplary process described herein. 
     Referring now to  FIG.  10   , an exemplary embodiment of a vacuum press  1000  suitable for performing the vacuum forming process is illustrated. In this embodiment, vacuum press  1000  includes a moveable portion  1002  and a base portion  1010 . Moveable portion  1002  is configured to move between an open and closed position in relation with base portion  1010  and allows an article to be placed on base portion  1010  for the vacuum forming process. In other embodiments, however, other configurations of a vacuum press with a different arrangement or different components, may be used. 
     In an exemplary embodiment, moveable portion  1002  of vacuum press  1000  includes a support  1004  surrounding and holding in place a flexible membrane  1006 . In some cases, flexible membrane  1006  may be any suitable flexible material, including, for example, silicone or rubber. In other cases, different flexible materials may be used. In addition, in some embodiments where heat is applied during the vacuum forming process, flexible membrane  1006  may further include heating elements or other mechanisms for providing heat to flexible membrane  1006 . In this embodiment, flexible membrane  1006  includes an outside surface  1008  and an opposite inside surface  1009 . Inside surface  1009  is configured to contact an article during the vacuum forming process and faces downward towards base portion  1010  of vacuum press  1000 . 
     In some embodiments, base portion  1010  may include features configured to assist with holding an article in place in vacuum press  1000  during the vacuum forming process. In an exemplary embodiment, where an article of footwear, for example, article  100 , is being vacuum formed, base portion  1010  may include a last  1012  that is configured to receive an upper or bootie of an article of footwear. In this embodiment, last  1012  is arranged with a bottom surface  1014  oriented in an upwards direction away from base portion  1010  and facing towards inside surface  1009  of flexible membrane  1006 . With this arrangement, a bottom portion of an upper or bootie that is configured to extend under the foot of a wearer can be placed on bottom surface  1014  of last  1012  to assist with forming the knit outsole. 
     Referring now to  FIG.  11   , insert member  300  is shown being placed onto bottom surface  1014  of last  1012  in preparation of vacuum forming the knit outsole using vacuum press  1000 . As shown in this embodiment, top side  302  of insert member  300  is placed onto bottom surface  1014  of last  1012  such that bottom side  304  of insert member  300  that includes protuberances  310  is facing upwards away from base portion  1010  of vacuum press  1000 . With this arrangement, last  1012  may be ready to receive an upper or bootie of an article of footwear for the vacuum forming process of a knit outsole. 
     Next, as shown in  FIG.  12   , upper  120  that includes knitted component upper portion  130  and knitted component lower portion  111  formed of unitary knit construction so to form a one-piece foot-enclosing bootie is prepared for the vacuum forming process. In an exemplary embodiment, upper  120  is placed in an inverted position over last  1012  having insert member  300  disposed on bottom surface  1014 , as described above in reference to  FIG.  11   . In one embodiment, ankle opening  121  may facilitate placement of upper  120  over last  1012  such that insert member  300  may be located within the interior of upper  120 . 
     Referring now to  FIG.  13   , upper  120  has been placed over last  1012  having insert member  300  disposed on bottom surface  1014 . In this configuration, bottom side  304  of insert member  300  that includes protuberances  310  is placed in loose relation with outsole top surface or side  113  within the interior of upper  120 . Outsole bottom surface or side  114  of knitted component lower portion  111  faces outwards away from base portion  1010  of vacuum press  1000 . As shown in  FIG.  13   , protuberances  310  on insert member  300  may form loose mounds or lumps in outsole bottom surface  114  of knitted component lower portion  111  prior to the application of the vacuum forming step. 
     Next,  FIG.  14    illustrates moveable portion  1002  of vacuum press  1000  being moved towards base portion  1010  to place vacuum press  1000  in a closed position before application of the vacuum forming step. As shown in this embodiment, inside surface  1009  of flexible membrane  1006  is being brought towards outsole bottom surface  114  arranged on last  1012 .  FIG.  15    illustrates vacuum press  1000  in a closed position with moveable portion  1002  brought into contact with base portion  1010 . Together, moveable portion  1002  and base portion  1010  form a seal with flexible membrane  1006  disposed around and covering last  1012 . As shown in  FIG.  15   , outside surface  1008  of flexible membrane  1006  extends upwards and away from base portion  1010  where last  1012  having upper  120  placed thereon is located. In this embodiment, vacuum press  1000  is prepared for the application of the vacuum forming process. 
       FIG.  16    illustrates a representation of the vacuum forming process using vacuum press  1000  on last  1012  having upper  120  placed thereon. As shown in this embodiment, the application of a vacuum within the interior of vacuum press  1000  between moveable portion  1002  and base portion  1010  draws flexible membrane  1006  down towards base portion  1010 . With this configuration, inside surface  1009  of flexible membrane  1006  exerts pressure onto upper  120  placed upon last  1012 , including insert member  300  located on bottom surface  1014  of last  1012 . Accordingly, the pressure of the vacuum forming process causes knitted component lower portion  111  of upper  120  on last  1012  to be drawn down onto bottom side  304  of insert member  300  that includes protuberances  310 . In some embodiments, heat also may be applied during the vacuum forming process along with the pressure from the vacuum. 
     Referring now to  FIG.  17   , moveable portion  1002  is moved to the open position away from base portion  1010  after the application of the vacuum forming process. In this embodiment, knit outsole  112  including cleat members  115  is shown formed on outsole bottom surface  114  of knitted component lower portion  111  of upper  120  placed on last  1012 . As described above, the location, size, and arrangement of cleat members  115  corresponds and aligns with the location, size, and arrangement of protuberances  310  on bottom side  304  of insert member  300  that has been placed on last  1012 . With this arrangement, a one-piece foot-enclosing bootie may be formed with a knit outsole. 
     In addition, insert member  300  may be used not only for forming the knit outsole during the vacuum forming process, such as process  800  described above, but may also remain disposed with the interior of upper  120  and placed in relation with outsole top surface  113  such that protuberances  310  align with and fill cavities of cleat members  115 . With this arrangement, insert member  300  may both form knit outsole  112  and provide cushioning to a foot of a wearer and/or reinforcement to cleat members  115 . 
     In some embodiments, additional components or elements may be associated with a sole system, including sole system  110 , to provide for enhanced traction and/or wear resistance to portions of the article of footwear. In an exemplary embodiment, sole system  110  may include provisions that at least partially cover portions of cleat members  115  on outsole bottom surface  114 . In one embodiment, sole system  110  may include cap elements  1800  that at least partially cover portions of cleat members  115  on outsole bottom surface  114  of knit outsole  112 . In this embodiment, cleat face  116  of cleat members  115  is formed from a knit surface of knitted component lower portion  111  and cap elements  1800  may be attached or joined to cleat face  116  to at least partially cover this knit surface. 
     In an exemplary embodiment, cap elements  1800  may include a top side  1802  and an opposite bottom side  1804 . As shown in  FIG.  19   , top side  1802  of cap element  1800  is configured to face away from outsole bottom surface  114  and may directly engage with a ground surface when an article is worn. Bottom side  1804  of cap element  1800  is configured to be attached or joined with cleat face  116  on cleat member  115 . In various embodiments, cap elements  1800  may be joined with or attached to cleat face  116  using any suitable mechanism. For example, in some cases, cap elements  1800  may be bonded to cleat face  116  using a thermoplastic polymer material. In other cases, cap elements  1800  may be attached to cleat face  116  by directly forming cap elements  1800  onto the knit surface using a molding or printing process. In still other cases, cap elements  1800  may be adhesively joined to cleat face  116 . Additionally, in some embodiments, portions of a knitted component forming a knit outsole, including knitted component lower portion  111 , may include yarns that facilitate or assist with attaching cap elements  1800  to the knit outsole. For example, fusible yarns or yarns incorporating a thermoplastic polymer material may be used to facilitate or assist with attaching cap elements  1800  to the knit outsole. 
     In some embodiments, cap elements  1800  may be formed from any suitable material that may be used to form a traction element or an outsole. Examples of suitable materials include, but are not limited to: polymers, elastomers, siloxanes, natural rubber, other synthetic rubbers, aluminum, steel, natural leather, synthetic leather, plastics, or other materials suitable for providing traction or protection. With this configuration, cap elements  1800  may cover portions of cleat face  116  of cleat members  115  so as to provide wear protection to the knit surface of knitted component lower portion  111  forming knit outsole  112 . In addition, cap elements  1800  may also be configured to provide enhanced traction or a gripping surface to cleat members  115  and/or portions of the knit outsole  112 . 
       FIGS.  18  and  19    illustrates an exemplary embodiment of cap element  1800  that has a shape that approximately corresponds with and is similar to the shape of cleat face  116 . However, in other embodiments, a cap element may have different shapes and/or configurations.  FIG.  20  through  23    various alternate embodiments of cap elements that may be used with knit outsole  112  to at least partially cover a portion of one or more cleat members  115 . 
     Referring now to  FIG.  20   , an alternate embodiment of a cap element  2000  is illustrated. In an exemplary embodiment, cap element  2000  may entirely cover cleat face  116  of cleat member  115 , as well as extending up along one or both sides of cleat member  115 . In this embodiment, cap element  2000  includes a lower portion  2002  that covers cleat face  116  of cleat member  115  and two extending portions  2004  disposed on either side of lower portion  2002  that extend away from lower portion  2002  along the sides of cleat member  115  towards outsole bottom surface  114 . In some cases, extending portions  2004  may extend at least partially along the sides of cleat member  115 . In other cases, extending portions  2004  may extend the entirety of the sides of cleat member  115  to an area adjacent to or abutting with outsole bottom surface  114 . With this configuration, an entirety of cleat member  115 , or at least a substantial majority of cleat member  115 , may be covered by cap element  2000 . In some cases, cap element  2000  may be used in embodiments where additional protection or rigidity for cleat member  115  of knit outsole  112  is desired, in addition to enhanced traction that may be generally provided by a cap element. 
     Referring now to  FIG.  21   , another alternate embodiment of a cap element  2100  is illustrated. In an exemplary embodiment, cap element  2100  may extend less than the entirety of cleat face  116  of cleat member  115 . In this embodiment, cap element  2100  includes a lower portion  2102  that covers less than the entirety of cleat face  116  of cleat member  115 . In an exemplary embodiment, cap element  2100  may be located approximately a first distance D 1  from one side of cleat member  115  and a second distance D 2  from the opposite side of cleat member  115 . In some cases, first distance D 1  and second distance D 2  may be approximately equal so as to center cap element  2100  and lower portion  2102  on cleat face  116  of cleat member  115 . In other cases, first distance D 1  and second distance D 2  may be different so as to offset cap element  2100  towards one side or the other of cleat face  116 . With this configuration, a portion less than the entirety of cleat face  116  of cleat member  115  may be covered by cap element  2100 . In some cases, cap element  2100  may be used in embodiments where enhanced traction for specific portions of cleat member  115  of knit outsole  112  is desired. 
     Referring now to  FIG.  22   , another alternate embodiment of a cap element  2200  is illustrated. In an exemplary embodiment, cap element  2200  may entirely cover cleat face  116  of cleat member  115 , as well as extending up along one or both sides of cleat member  115  and also covering a portion of outsole bottom surface  114 . In this embodiment, cap element  2200  includes a lower portion  2202  that covers cleat face  116  of cleat member  115  and further extends on either side of cleat member  115  and towards outsole bottom surface  114 , where cap element  2200  also covers at least a portion of outsole bottom surface  114 . In some cases, cap element  2200  may be configured in the shape of a semi-spherical or hemi-spherical dome that covers over cleat member  115 . In other cases, cap element  2200  may have a different shape that covers cleat member  115  and a portion of outsole bottom surface  114 . With this configuration, an entirety of cleat member  115  and a portion of outsole bottom surface  114  may be covered by cap element  2200 . In some cases, cap element  2200  may be used in embodiments where a change in the shape of cleat member  115  of knit outsole  112  is desired, or where the material forming cap element  2200  is used to reinforce sides of cleat member  115 , in addition to enhanced traction that may be generally provided by a cap element. 
     Referring now to  FIG.  23   , another alternate embodiment of a cap element  2300  is illustrated. In an exemplary embodiment, cap element  2300  may have a tiered configuration that presents at least two different surfaces having different heights extending away from cleat face  116  of cleat member  115  in the vertical direction. In an exemplary embodiment, tiered cap element  2300  may combine features of previous embodiments of cap elements, described above. For example, in this embodiment, tiered cap element  2300  may generally include the features of cap element  1800  with the features of cap element  2100 . As shown in  FIG.  23   , tiered cap element  2300  includes a lower portion  2302  that covers cleat face  116  of cleat member  115 , and presents a first surface located at a first height from cleat face  116 . In addition, tiered cap element  2300  further includes an upper portion  2310  that presents a second surface  2312  located at a second height from cleat face  116  that is greater than and located on top of the first surface of lower portion  2302 . With this configuration, benefits of multiple configurations of cap elements may be combined with cap element  2300 . In other embodiments, other features of the various embodiments of cap elements described above may be similarly combined together into other embodiments of a cap element for use with knit outsole  112  and sole system  110 . 
     In some embodiments, rather than providing individual cap elements to cover each cleat member  115  of knit outsole  112 , an outsole cover assembly may be provided to cover all of knit outsole  112 , including cleat members  115  and outsole bottom surface  114 .  FIGS.  24  through  26    illustrate an exemplary embodiment of an outsole cover assembly  2400  that may be configured to cover all of knit outsole  112 , including cleat members  115  and outsole bottom surface  114 . 
     Referring now to  FIG.  24   , outsole cover assembly  2400  is shown in exploded relation with article  100 . In an exemplary embodiment, outsole cover assembly  2400  has a top surface  2402  and an opposite bottom surface  2404 . Top surface  2402  is configured to be brought in relation with outsole bottom surface  114 . In some cases, top surface  2402  of outsole cover assembly  2400  may be joined with or attached to outsole bottom surface  114  of knit outsole  112  using any of the methods described above for attaching a cap element to cleat members  115  of knit outsole. Bottom surface  2404  of outsole cover assembly  2400  is configured to interact with a ground surface and may assist with providing durability, protection, and/or traction to sole system  110  of article  100 . 
     In some embodiments, outsole cover assembly  2400  may be formed with one or more recesses  2412  in top surface  2402  of outsole cover assembly  2400  that are configured to align with and correspond to cleat members  115  on outsole bottom surface  114  of knit outsole  112 . In an exemplary embodiment, the location, size, and arrangement of recesses  2412  of outsole cover assembly  2400  may be selected to be substantially similar to the location, size, and arrangement of cleat members  115  on outsole bottom surface  114  of knit outsole  112 . In one embodiment, recesses  2412  form cleat cover elements  2410  that extend outward from bottom surface  2404  of outsole cover assembly  2400 . With this configuration, an entirety of cleat member  115  and outsole bottom surface  114  of knit outsole  112  may be covered by cleat cover elements  2410  and outsole cover assembly  2400 . Accordingly, as shown in  FIG.  25   , when knit outsole  112  of article  100  is brought in relation to and joined with outsole cover assembly  2400 , cleat members  115  are received into recesses  2412  of outsole cover assembly  2400 . 
     In some embodiments, outsole cover assembly  2400  may further include a lip  2414  that extends around an outer periphery along a peripheral edge of outsole cover assembly  2400 . Lip  2414  may be configured to extend above top surface  2402  of outsole cover assembly  2400  along the outer periphery to form a wall or raised portion. Additionally, lip  2414  may define a shape of the outer periphery of outsole cover assembly  2400  that is substantially similar to and corresponds with the shape of knit outsole  112 , including outsole bottom surface  114 . In some embodiments, when article  100  is brought in relation with outsole cover assembly  2400 , lip  2414  may at least partially extend upwards along medial or lateral sides of knitted component lower portion  111 , as shown in  FIG.  26   . With this configuration, lip  2414  may assist with aligning article  100  within outsole cover assembly  2400  and also assist with providing support and/or rigidity to portions of sole system  110  and article  100 . 
     In various embodiments, outsole cover assembly  2400  may be made from any suitable material, including any of the materials described above for making a cap element, as well as any other suitable materials for making an outsole. In addition, while in the present embodiments outsole cover assembly  2400  covers substantially all of knit outsole  112  and cleat members  115 , in other embodiments, an outsole cover assembly may cover only portions of knit outsole  112  and/or selected cleat members  115  located in specific portions or regions of sole system  110 . With this configuration, desired additional durability, wear resistance, rigidity, and/or traction may be provided by an outsole assembly in selected areas of sole system  110 . 
     While various embodiments of the invention have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims. As used in the claims, “any of”, when identifying the previous claims, is intended to mean (i) any one claim or (ii) any combination of two or more claims identified.