Patent Publication Number: US-9833044-B2

Title: Cleated article of footwear

Description:
BACKGROUND 
     It is advantageous, when participating in various athletic activities, to have footwear that provides traction and stability. Accordingly, sole structures for articles of footwear have been developed with cleat members to provide traction on a variety of surfaces. In particular, articles of footwear with interchangeable or removable cleats have been developed for sports, such as football, soccer, rugby, baseball, and golf. 
     After a period of use, cleat members on an article of footwear can become worn down. In the past, this would require replacement of the entire shoe. Removable cleats on an article of footwear were developed so that worn down cleat members could be easily removed and replaced with new cleat members. Removable cleat members also allow the user to select varied sizes or lengths of cleat members depending on the playing surface or the user&#39;s preference. 
     Cleat members have been previously developed with a ground-contacting portion on the bottom and a threaded portion on the top. Threaded portions on cleat members have been provided with either a single start thread or multi-start thread. 
     Single start threads provide a strong connection. However, the high number of turns required to attach and detach the cleat member with a single start thread becomes extremely time consuming. Multi-start threads have a steeper thread angle which enables the cleat member to be attached and detached with less rotation. Additionally, a multi-start thread is deeper cut than a single start thread, making the shear strength of the thread greater, so a shorter thread post can be used. However, known multi-start threaded cleat members may require additional locking mechanisms to prevent accidental loosening or unscrewing of the cleat member from the article of footwear. 
     Additional locking mechanisms may increase the weight of the cleat member and therefore the overall weight of the article of footwear. When additional locking mechanisms are included, the seal between the cleat member and the sole of an article of footwear may be more susceptible to debris collection, the additional mechanisms may be more susceptible to damage, and the cleat members may be more costly to manufacture. 
     There exists a need in the art for a cleat member for an article of footwear that provides quick attachment and release with minimal rotation, resistance to accidental loosening, a complete seal from debris, and a lightweight profile. 
     SUMMARY 
     The present disclosure is directed to improvements in cleat systems for articles of footwear, including provisions for quick attachment and release of cleat members, resistance to accidental loosening of cleat members during use, and providing a seal from debris at the interface of cleat members and the sole of the article of footwear. 
     For example, the present invention may include a removable cleat system for an article of footwear. The removable cleat system may include a cleat member having a multi-start thread arrangement configured to be attached to a base member incorporated into the sole of the article of footwear. In some embodiments, the cleat member may include three multi-start threads, each thread extending approximately 120 degrees or less about a fastening portion of the cleat member. In addition, the threads of the cleat member may have a changing draft angle. In order to provide increased binding force, the female threads of the base member may have a substantially constant draft angle. The threads of the cleat member may also include textured surfaces to increase binding within the base member. 
     In one aspect, the present disclosure is directed to an article of footwear including an upper and a sole including at least one base member. The base member may include a fastener receiving portion, the fastener receiving portion including at least one female thread. The cleat member may include a cleat body, the cleat body including a ground-engaging end and an opposite fastening end. The cleat member may further include a fastening portion extending from the fastening end of the cleat body. The fastening portion may be configured to engage with the fastener receiving portion of the at least one base member, the fastening portion including a post and at least one thread that extends around the post. The thread of the cleat member may be configured to engage with the female thread of the base member. 
     In another aspect, the present disclosure is directed to a cleat system for an article of footwear. The cleat system may include a base member configured to be disposed in a sole of an article of footwear. The base member may include a fastener receiving portion. The fastener receiving portion may include at least one female thread. The cleat system may also include a cleat member including a cleat body. The cleat body may include a ground-engaging end and an opposite fastening end. A fastening portion may extend from the fastening end of the cleat body. The fastening portion may be configured to engage with the fastener receiving portion of the at least one base. The fastening portion may include a post and at least one thread that extends around the post. The thread may include a draft angle, wherein the thread of the cleat member is configured to engage with the female thread of the base member. 
     In another aspect, the present disclosure is directed to a cleat member for an article of footwear. The cleat member may include a cleat body including a ground-engaging end and an opposite fastening end. The cleat member may further include a fastening portion extending from the fastening end of the cleat body. The fastening portion may be configured to be removably engaged with a fastener receiving portion disposed on a base on a sole of the article of footwear. The fastening portion of the cleat member may include a post and at least one thread that extends around the post. The thread may further include a draft angle. 
     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 different views. 
         FIG. 1  is an isometric view of an exemplary embodiment of an article of footwear configured with cleat members; 
         FIG. 2  is a bottom perspective view of an exemplary embodiment of an article of footwear configured with cleat members; 
         FIG. 3  is an enlarged view of an exemplary embodiment of a cleat member configured to releasably attach to a base member disposed in a sole of an article of footwear; 
         FIG. 4  is an exploded view of an exemplary embodiment of a cleat member configured to releasably attach to a base member disposed in a sole of an article of footwear; 
         FIG. 5  is a representative view of an exemplary embodiment of a cleat member being releasably attached to a base member in a sole; 
         FIG. 6  is a representative view of an exemplary embodiment of a cleat member interlocking with a base in a sole; 
         FIG. 7  is a representative view of an exemplary embodiment of a cleat member releasably attached to a base member with an interlocking arrangement; 
         FIG. 8  is a schematic view of an exemplary embodiment of a cleat system; 
         FIG. 9  is a side view of an exemplary embodiment of a cleat member; 
         FIG. 10  is a cross-sectional view of an exemplary embodiment of a cleat member taken at section line  10 - 10  in  FIG. 9 ; 
         FIG. 11  is a cross-sectional view similar to  FIG. 10 , illustrating a draft angle of threads of a cleat member; 
         FIG. 12  is an exploded view of an exemplary embodiment of a cleat system including a cleat member and a base member configured for interlocking arrangement; 
         FIG. 13  is a top view of an exemplary embodiment of a cleat member; 
         FIG. 14  is a cross-sectional view of an exemplary embodiment of a base member; 
         FIG. 15  is a cross-sectional view of an exemplary embodiment of a cleat member; 
         FIG. 16  is a cross-sectional view of an exemplary embodiment of a cleat member and a base member with an interlocking arrangement; 
         FIG. 17  is a partial cross-sectional view of an exemplary embodiment of a cleat member being releasably attached to a base member; 
         FIG. 18  is a partial cross-sectional view of an exemplary embodiment of a cleat member being releasably attached to a base member; 
         FIG. 19  is a partial cross-sectional view of an exemplary embodiment of a cleat member releasably attached to a base member in an interlocking arrangement; and 
         FIG. 20  is a cross-sectional view of an exemplary embodiment of a cleat member releasably attached to a base member in a sole of an article of footwear. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is an exemplary embodiment of an article of footwear  100 . For clarity, the following detailed description discusses an exemplary embodiment, which may be suitable for use as a football shoe, but it should be noted that the present invention could take the form of any article of footwear including, but not limited to, soccer shoes, rugby shoes, baseball shoes as well as other types of shoes. As shown in  FIG. 1 , article of footwear  100 , also referred to as footwear  100 , is intended to be used with a left foot, however it should be understood that the following discussion may equally apply to a mirror image of article of footwear  100  that is intended for use with a right foot. 
     In some embodiments, article of footwear  100  may include one or more components. In an exemplary embodiment, footwear  100  may include an upper  102  configured to receive a wearer&#39;s foot, and a sole  104  secured to upper  102 . For clarity, only a portion of upper  102  is shown in  FIG. 1 . Generally, upper  102  may be any suitable type of upper. In particular, upper  102  could have any design, shape, size, and/or color. For purposes of illustration, upper  102  is shown generally in this embodiment. 
     Sole  104  may be fixedly attached to a bottom portion of upper  102 . In some embodiments, sole  104  may include one or more layers. For example, sole  104  may include an outsole, as shown in  FIG. 1 . Further, in some embodiments, the outsole may include multiple components and/or layers. For example, in some cases, the outsole may include one or more reinforcing plates, which may be part of a multi-layer outsole construction. In addition, although not shown in the figures, in some embodiments, sole  104  may include a midsole, which may provide cushioning and control of ground reaction forces. Further, in some embodiments, sole  104  may include an insole (also not shown), which may provide comfort, fit, and additional cushioning properties. 
     In some embodiments, sole  104  may include a ground-facing surface  106 . Ground-facing surface  106  may be configured to contact ground surfaces, including, but not limited to dirt, natural grass, synthetic grass or turf, as well as other types of playing surfaces. Sole  104  may also include a foot-side surface (not shown) disposed on an opposite side of sole  104  than ground-facing surface  106 . In an exemplary embodiment, the foot-side surface may be configured to contact a portion of upper  102 , a midsole layer, and/or an insole layer of footwear  100 . 
     Generally, each component of article of footwear  100  may be constructed of any suitable material. For example, one or more portions of sole structure may be constructed from any suitable material, including but not limited to elastomers, siloxanes, natural rubber, other synthetic rubbers, aluminum, steel, natural leather, synthetic leather, or plastics. Also, upper  102  may be made from any suitable material, including but not limited to, nylon, natural leather, synthetic leather, natural rubber, or synthetic rubber. 
     In some embodiments, the sole may include provisions for increasing traction with a ground surface. In some cases, the sole may include one or more cleat members to enhance traction with a ground surface. Generally, the term “cleat” or “cleat members”, as used in this detailed description and throughout the claims, includes any provisions disposed on a sole for increasing traction through friction and/or penetration of a ground surface. Alternatively, a cleat or cleat members may also be known as a “stud” or as “stud members”. Typically, cleat members may be configured for particular uses, including but not limited to, football, soccer, baseball, rugby, golf or any type of activity that requires traction. 
       FIG. 2  illustrates a bottom view of an exemplary embodiment of footwear  100  including cleat members. As shown in  FIG. 2 , in some embodiments, footwear  100  may include a plurality of cleat members  108 . For example, cleat members  108  may include a first cleat member  201 , a second cleat member  202 , a third cleat member  203 , a fourth cleat member  204 , a fifth cleat member  205 , a sixth cleat member  206 , and a seventh cleat member  207 . 
     Footwear  100  may include any suitable number of cleat members  108  provided on sole  104 . In addition, cleat members  108  may be positioned in any suitable arrangement on sole  104 . As shown in  FIG. 2 , cleat members  108  may be disposed in one or more regions of footwear  100 , including one or more of a forefoot region, a mid-foot region, and/or a heel region. In some embodiments, first cleat member  201 , second cleat member  202 , third cleat member  203 , fourth cleat member  204 , and fifth cleat member  205  may be located in a forefoot region of footwear  100 , as shown in  FIG. 2 . In addition, in some embodiments, sixth cleat member  206  and seventh cleat member  207  may be located in a heel region of footwear  100 , as also shown in  FIG. 2 . 
     In some embodiments the footwear may include a customizable sole. For example, one or more of the cleat members may be removable from the sole. Providing cleat members that are removable may enable the wearer to replace worn down cleat members. In addition, cleat members of one size and configuration may be exchanged for cleat members having a different size and/or configuration. This may enable the wearer to choose cleat members to suit the conditions from game to game. The wearer may make the selection based on a variety of factors. For example, in some cases shorter cleat members may be selected for firm and/or dry surfaces, whereas longer cleat members may be selected for soft and/or wet surfaces. Other factors may also be considered when selecting cleat members for game-to-game use. In order to provide the cleat members with removability, the footwear may include a fastening system. The fastening system may include fastener features on the cleat member and associated with the sole. For example, in some embodiments, the cleat members may be removably attached to the sole using threaded connections. 
     In some embodiments, one or more of cleat members  108  may be removably attached to sole  104 , for example, using fasteners that are configured to be engaged with corresponding receiving elements within sole  104 . For example, in some embodiments, footwear  100  may include a cleat system. For example, as shown in  FIG. 2 , the cleat system may include first cleat member  201 . In addition, the cleat system may also include a base member  320  disposed in sole  104  and configured to receive first cleat member  201 . The cleat system, including first cleat member  201  and base member  320 , is discussed in greater detail below. 
     In some configurations the footwear may include provisions to reduce weight and simplify construction. For example, in some embodiments, only the cleat members that are more frequently desired to be interchanged may be removable, and the other cleat members on the footwear may be integrally formed with the sole. In some cases, the cleat members that are more frequently desired to be changed may be in the forefoot region. In other cases, the cleat members that are more frequently desired to be changed may be in the heel region. This variance in the frequency with which cleat members are desired to be changed may be related to multiple factors. In some cases, cleat members in one region of the footwear may wear down more quickly. Additionally, or alternatively, cleat members in certain regions of the footwear may be more desirable to be changed to a different size and/or configuration depending on the field conditions. 
     While one or more of cleat members  108  may be removable, plurality of cleat members  108  may also include one or more cleat members that are integrally formed with sole  104 . That is, in some embodiments, sole  104  may include one or more integral cleat members and one or more removable cleat members. For example, in some cases, cleat members in the forefoot region may be removable and cleat members in the heel region may be integrally formed with sole  104 . For instance, first cleat member  201 , second cleat member  202 , third cleat member  203 , fourth cleat member  204 , and fifth cleat member  205  may be removably attached to sole  104 , while sixth cleat member  206  and seventh cleat member  207  in the heel region may be integrally formed with sole  104 . In other cases, cleat members in the forefoot region may be integrally formed with sole  104  and cleat members in the heel region may be removable. For example, in some embodiments, first cleat member  201 , second cleat member  202 , third cleat member  203 , fourth cleat member  204 , and fifth cleat member  205  may be integrally formed with sole  104  and sixth cleat member  206  and seventh cleat member  207  may be removably attachable to sole  104 . 
     Since the footwear may include any suitable number of cleat members, the sole may include a corresponding number of base members to receive any number of removable cleat members. In some embodiments, each of the removable cleat members may be engaged with a base member on the sole. Accordingly, base members on a sole may be arranged in any particular design or pattern on any portion of a sole. Particular arrangements of base members and corresponding cleat members may be associated with different sports or different player positions within a sport. As shown in  FIG. 2 , a plurality of cleat members  108  may be releasably attached to the sole  104 . Accordingly, a corresponding number of base members may also be arranged on a forefoot region and/or a heel region of the sole, as shown. In other embodiments, base members may be disposed in other suitable patterns. 
     Referring now to  FIG. 3 , first cleat member  201  is illustrated as installed in ground-facing surface  106  of sole  104 . For example, as shown in  FIG. 3 , first cleat member  201  may be screwed into a base member disposed in sole  104 . The installation of first cleat member  201  in the base member is described in greater detail below. 
       FIG. 4  illustrates an exploded view of an exemplary embodiment of first cleat member  201  and base member  320 . In this embodiment, first cleat member  201  is configured to releasably attach to a fastener receiving portion  322  disposed within base member  320  in sole  104 . While  FIG. 4  illustrates the attachment of first cleat member  201  to fastener receiving portion  322 , it should be understood that the remaining plurality of cleat members  108  may be attached in a substantially similar manner to additional fastener receiving portions disposed within additional base members of sole  104 . 
     As shown in  FIG. 4 , first cleat member  201  includes a cleat body  304  having a ground-engaging end  300  and an opposite fastening end  302 . Ground-engaging end  300  is configured to contact a ground surface. Fastening end  302  may be located towards the point of attachment between cleat  200  and base member  320 . Ground-engaging end  300  is disposed at a portion of cleat member  200  that is located further from ground-facing surface  106  of sole  104 , when first clear member  201  is installed in sole  104 . Fastening end  302  is disposed at a portion of cleat member  200  that is located proximate to ground-facing surface  106  of sole  104 . 
     In some embodiments, for example, as shown in  FIG. 4 , cleat body  304  may have a generally truncated conical shape. In other embodiments, cleat body  304  may have other shapes. In the embodiment shown in  FIG. 4 , first cleat member  201  includes a ground-engaging portion  306  that is disposed at ground-engaging end  300  of cleat member  200 . Ground-engaging portion  306  of cleat member  200  may be configured to contact and/or penetrate a ground surface. 
     In some embodiments, first cleat member  201  may include a lip  308 . For example, as shown in  FIG. 4 , lip  308  may be a portion of cleat body  304  disposed adjacent to fastening end  302 . In an exemplary embodiment, lip  308  may define an outer periphery of cleat body  304  of first cleat member  201 . In cases where cleat body  304  has a generally truncated conical shape, lip  308  may be associated with a wider portion of cleat body  304 . Ground-engaging portion  306  may be associated with the narrower portion of cleat body  304 . In other words, cleat body  304  may taper from a wider portion associated with lip  308  to a narrower portion associated with the ground-engaging portion  306 . 
     The cleat body may have additional provisions to facilitate installation and removal of the cleat member from the sole. For example, the cleat body may include provisions for engaging a tool that may be used to attach the cleat member to an article of footwear. For instance, in some cases, cleat body may include one or more grasping portions. Generally, the grasping portions may be recesses disposed on the cleat body. Grasping portions may have any suitable size and shape. Examples of various shapes include, but are not limited to, rectangles, squares, circles, ovals, polygonal and irregular shapes, as well as any other type of shape. Additionally, the depth of grasping portions can vary. By using different shapes recessed with different depths, grasping portions may be configured to engage a tool to attach a cleat member to an article of footwear. The absence of material in the recess may reduce the weight of a cleat member. 
     As shown in  FIG. 4 , at least one grasping portion  312  may be disposed on cleat body  304 . As further shown in  FIG. 4 , in an exemplary embodiment, grasping portion  312  may have a generally triangular shape. With this configuration, grasping portion  312  may engage a tool to secure first cleat member  201  to sole  104  of an article of footwear. 
     In some embodiments, cleat body  304  may be configured with multiple grasping portions that are substantially similar to grasping portion  312 . In some embodiments, first cleat member  201  may include three grasping portions. In some cases, the grasping portions may be disposed in an approximately evenly-spaced configuration around cleat body  304 . In other embodiments, a cleat member may include more or fewer grasping portions, which may be spaced evenly or unevenly around the cleat body of the cleat member. 
     As shown in  FIG. 4 , some embodiments, fastening portion  310  may extend outward from fastening end  302  of cleat body  304 . Additionally, fastening portion  310  may be configured to releasably attach first cleat member  201  to fastener receiving portion  322  of base member  320  in sole  104 . Generally, fastening portion  310  may be configured in any suitable manner to engage fastener receiving portion  322 . In particular, fastening portion  310  may be configured with a diameter sufficient to engage and fit within fastener receiving portion  322 . 
     In some embodiments, fastening portion  310  may include threading to engage fastener receiving portion  322 . For example, as seen in  FIG. 4 , fastening portion  310  may include a post  314  and at least one thread  316  that extends around the post  314 . Fastening portion  310  may be associated with any type of thread, including threads having various sizes and pitch diameters. In this arrangement, fastening portion  310  may be screwed into fastener receiving portion  322 . 
     As discussed above, the sole on the article of footwear may be provided with features configured to receive the fastening portion of the cleat members. In some embodiments, the sole may include a base member that features provisions that are capable of quickly receiving a cleat member. For example, the base member may include at least one female thread and an opening that is capable of receiving a cleat member. 
     As shown in  FIG. 4 , base member  320  may be disposed in sole  104 . In some embodiments, base member  320  may include fastener receiving portion  322  that is capable of receiving fastening portion  310  of cleat body  304 . As shown in  FIG. 4 , fastener receiving portion  322  may include a thread opening  326  that is configured to receive at least one thread  316  on first cleat member  201 . In an exemplary embodiment, fastener receiving portion  322  may include multiple thread openings that would accept a multi-start thread. The number of thread openings included on the base member may correspond directly to the number of threads on the cleat member. For example, in some embodiments, fastener receiving portion  322  may include three thread openings, as shown in  FIG. 4 , which may be configured to receive three threads of a cleat member. 
     In some embodiments, base member  320  may be integrally formed with sole  104 . For example, in such embodiments, base member  320  may be formed by molding fastener receiving portion  322  into sole  104  or by machining the cavity defined by fastener receiving portion. Such a configuration may expedite manufacturing, simplify construction, and reduce weight by eliminating additional materials. Such a configuration may also provide increased strength since there is not a separate piece to become detached from sole  104 . 
     In some embodiments, base member  320  may be formed of a separate piece of material. Such a separate piece of material may be attached to sole  104  in any suitable manner. For example, in some embodiments, base member  320  may be adhesively attached to sole  104 . In some embodiments, base member  320  may be press-fit (i.e., friction-fit) within a recess in sole  104 . In other embodiments, base member  320  may be co-molded with sole  104 . Further, base member  320  may be attached to sole  104  using any other suitable method. 
     Forming base member  320  as a separate piece of material from sole  104  may provide flexibility with manufacturing, by enabling the use of varied configurations. In addition, it would enable base member  320  to be formed of a different material than sole  104 . In some cases base member  320  may be formed of a stronger and/or more rigid material than sole  104 , which may reinforce the anchor point of first cleat member  201 . Alternatively, in some embodiments, base member  320  may be formed of a less rigid and/or more compressible material than sole  104 . The reduced rigidity and/or increased compressibility may provide increased comfort and/or improved ground contact by enabling first cleat member to move axially with respect to sole  104  and/or to deflect horizontally with respect to sole  104 . 
     In some embodiments, the base member may include one or more features that secure the base member within the sole. For example, in some embodiments, the base member may include a rim (or lip) that extends radially away, in a substantially horizontal direction, from an upper portion of the base member. By including a rim having a larger diameter compared to the lower portion of the base member, the rim may secure the base member within the sole by preventing the base member from being pulled out of the sole. 
     For example, as shown in  FIG. 4 , in some embodiments, base member  320  may include an upper rim  328  extending from an upper portion of base member  320 . Upper rim  328  may be wider than the lower portion of base member  320 . As shown in  FIG. 4 , base member  320  may include a bottom face  324 , which may have a smaller size than upper rim  328 . As shown in  FIG. 4 , bottom face  324  may be substantially aligned (e.g., flush) with, and in abutting engagement with, ground-facing surface  106  of sole  104 . Accordingly, upper rim  328  may prevent the egress of base member  320  from the recess within sole  104  in which it lies. 
     In addition, base member  320  may also include one or more support members  330 , which may be configured to reinforce base member  320 . For example, as shown in  FIG. 4 , support members  330  may extend substantially radially from the main body of base member  320 , which may reinforce the base member  320  overall. In addition, support members  330  may extend downward from upper rim  328 , thus providing a reinforcing buttress between the main body of the base member  320  and the upper rim  328 . This may strengthen upper rim  328 . 
     The quick and secure attachment of a cleat member is beneficial to the user, especially when attaching or exchanging one or more cleat members on a sole. In some embodiments, the cleat member may be configured to be fully attached to the footwear in less than one complete turn (i.e., less than 360 degrees of rotation of the cleat member relative to the footwear). For example, in some embodiments, the cleat member may be configured to be fully attached to the footwear in less than approximately one half turn (i.e., 180 degrees). Further, in some embodiments, cleat members may be configured to be fully attached to a sole within approximately one-third turn (i.e., 120 degrees) or less.  FIGS. 5 through 7  illustrate the progression of a cleat member interlocking with a base member in a sole of an article of footwear in approximately one-third turn.  FIG. 5  shows the system just prior to engagement between the threads of the cleat member and the fastener receiving portion of the base member.  FIG. 6  shows the cleat member partially engaged after approximately one sixth of a turn.  FIG. 7  shows the cleat member fully engaged with the base member after another one sixth of a turn (one third turn total; i.e., approximately 120 degrees). 
     For purposes of this disclosure, the terms “fully attached,” “fully installed,” “fully engaged,” “full engagement,” “full attachment,” and other such terms will be understood to mean that the cleat member is completely screwed in as far as it will go. In such condition, the binding of the cleat member to the footwear is at its peak and the footwear is in condition for use. Further, in such condition, an upper lip of the body portion of the cleat member is in contact with the base member or the lower surface of the sole. 
     In some embodiments, a tool (not shown) may be used to turn first cleat member  201  into base member  320  of sole  104 . The tool may provide additional grip and torque for removal. In an exemplary embodiment, the tool may turn first cleat member  201  by engaging with one or more grasping portions  312 . In  FIGS. 5-7 , grasping portion  312 , which may be configured to receive a removal tool, is shaded for purposes of identification. Each of  FIGS. 5-7  shows both a perspective view and a bottom view. The location of the shaded grasping portion  312  illustrates the various positions of first cleat member  201  during the rotational installation, including a starting point shown in  FIG. 5 , a mid-point shown in  FIG. 6 , and a final position shown in  FIG. 7 . 
     As shown in  FIG. 5 , fastening portion  310  is aligned with fastener receiving portion  322  at the starting position of the installation process. For reference, this is indicated by the initial position of grasping portion  312 . Referring now to  FIG. 6 , first cleat member  201  is shown being screwed into base member  320  of sole  104 . For reference, grasping portion  312  is shown midway between the initial position and a final position in both the perspective view and bottom view of  FIG. 6 . As shown in  FIG. 7 , first cleat member  201  is fully installed securely attached to base member  320  in sole  104 . Accordingly, for reference, grasping portion  312  is shown in a final position in  FIG. 7 . In this exemplary embodiment, first cleat member  201  has been fully attached to base member  320  in approximately one-third turn (i.e., approximately 120 degrees of rotation about the central axis of first cleat member  201 ). With this fully attached arrangement, first cleat member  201  may resist becoming loose while the article of footwear is being worn. 
       FIG. 8  shows a schematic elevation view of cleat system  400 . As shown in  FIG. 8 , post  314  of cleat member  200  may include a proximal end  317  located furthest away from ground-engaging end  306 . In some embodiments, post  314  may also include a distal end  319  that is located opposite the proximal end  317  and closer to the ground-engaging end  306  of first cleat member  201 . In some embodiments, thread  316  may include a first proximal end  311  and a second distal end  313 . As shown in  FIG. 8 , the first proximal end  311  of thread  316  may be located at proximal end  317  of post  314 . Further, second distal end  313  may be opposite first proximal end  311  and proximate to distal end  319  of post  314 . 
     In some embodiments, cleat member may include provisions to reduce weight, increase binding force, increase durability, and prevent the introduction of debris between the cleat member and the footwear. For example, in some embodiments, a portion of the cleat body may be hollowed out around the post to form a recess. This structure may eliminate material from the cleat member, thus reducing weight. In addition, this absence of material may provide the outer lip of the cleat body with some flexibility. Due to this flexibility, the lip may deflect upon engagement with the sole or the base member. This deflection may increase the binding force between the components. In addition, this deflection may also provide a close fit, thus preventing the introduction of debris between the lip and the sole or base member. This arrangement also provides a shorter exposed fastening portion of the cleat member, thereby providing a shorter overall profile length of the cleat, which may increase durability. 
     As shown in  FIG. 8 , in some embodiments, first cleat member  201  may include a recess  318  extending around post  314 . Recess  318  may be defined between post  314  and an angled interior wall  340  that extends at an inward angle towards post  314  from lip  308  of cleat body  304 . Thus, fastening portion  310  of first cleat member  201  may include an upper exposed portion  414  and a recessed portion  406 . Recessed portion  406  of fastening portion  310  may extend partially below lip  308  and may be surrounded by recess  318  of cleat body  304 . Thus, the full length  418  of fastening portion  310  may be formed by exposed portion  414  and recessed portion  416 , as shown in  FIG. 8 . 
       FIGS. 9 and 10  illustrate similar views of first cleat member  201 .  FIG. 9  shows a side elevation view of cleat member  201 , and  FIG. 10  shows a cross-sectional view taken at section line  10 - 10  in  FIG. 9 . As shown in  FIG. 10 , in some embodiments, cleat body  304  and fastening portion  310  may be integrally molded. For example, the cleat body  304  and fastening portion  310  may be formed of a unitary piece of material. A cleat body of unitary construction may have greater strength than a cleat body that is formed from two different material elements joined together. A unitary cleat member may also be lighter weight. Unitary cleat members may also facilitate recycling, since the cleat member does not include different materials. However, in some embodiments, cleat body  304  and fastening portion  310  may be formed of separate pieces that are attached together. Two-piece cleat members may enable different materials to be used for the two components. Accordingly, materials may be more selectively chosen for their properties according to the desired characteristics of each component. For example, it may be desirable to utilize a relatively stronger material, such as a metal, for fastening portion  310 , whereas it may be desirable to utilize a relatively lightweight material, such as plastic, for cleat body  304 . 
     A cleat member may include provisions for quick attachment to a base member in an article of footwear. For example, in some embodiments, the cleat member may include a multi-start thread. Accordingly, the cleat member may include multiple threads. Each of the threads may have a relatively steep angle, and may extend less than a full revolution around the post of the cleat member. 
     As shown in  FIG. 9 , first cleat member  201  may include a multi-start thread  316 . For example, fastening portion  310  of first cleat member  201  may include three threads, including a first thread  406 , a second thread  408 , and a third thread  410 . In some embodiments, first thread  406 , second thread  408 , and third thread  410  may be spaced equally from one another. 
     Cleat members may be attached, as well as replaced, quickly when the length of the thread does not extend fully around the post of a cleat. As represented in  FIG. 9 , the threads may sweep around the post approximately 180 degrees. This forms a relatively steep thread, providing a large axial translation for a small amount of rotation. Accordingly, a 180 degree sweep around the post allows for quick attachment of the cleat member to the article of footwear. In such embodiments, the cleat member may be attached in approximately one-third of a turn (i.e., approximately 120 degrees of rotation of the cleat member). In some embodiments, the threads may each extend less than approximately 180 degrees around post  314 . Further, in some embodiments, the threads may each extend no more than approximately 120 degrees around post  314 . (This angular sweep of the threads is shown in further detail in  FIGS. 12 and 13 .) 
     In some embodiments, threads from the fastening portion may include features that lock the cleat in place and provide increased binding when the cleat is attached to the base member. For example, in some embodiments, the thread may include a draft angle, thereby giving the fastening portion of the cleat member an effective wedge-shape. That is, the thread may protrude from the post an increasing distance along the length of the thread. Thus, the more the cleat member is threaded into the fastener receiving portion of the base member, the tighter the thread may bind within the base member. To further increase the binding, the female thread of the fastener receiving portion may have a consistent depth, as opposed to a corresponding wedge-shape. Therefore, the wedge-shape of the male thread of the fastening portion of the cleat member may provide tight securement and increased binding of the cleat when inserted into the fastener receiving portion of the base member. Aspects of the interaction between the drafted thread of the cleat member and the female thread of the base member are discussed below with respect to  FIGS. 10-20 . 
     As noted above,  FIG. 10  shows a cross-sectional view of the cleat member taken at section line  10 - 10  in  FIG. 9 . In some embodiments, fastening portion  310  may include at least one thread that may have a draft angle, thus making the thread wedge-shaped. As shown in  FIG. 10 , each of first thread  406 , second thread  408 , and third thread  410  may have a draft angle. (In other embodiments, one or more of the threads may not include a draft angle.) That is, each of first thread  406 , second thread  408 , and third thread  410  may extend further from post  314  the further away from fastening end  302  the threads extend. For example, as shown in  FIG. 10 , in some embodiments, second thread  408  may extend a first radial distance R 1  from post  314  at one end of second thread  408  and a second radial distance R 2  from post  314  at a second end of second thread  408 . First radial distance R 1  may be located at proximal end  402  of second thread  408  closest to fastening end  302  of first cleat member  201 . Second radial distance R 2  may be located at a distal end  404  of second thread  408  closest to ground-engaging end  300  of first cleat member  201 . As shown in  FIG. 10 , first radial distance R 1  may be smaller than second radial distance R 2 . Thus, the second radial distance R 2  may be larger than first radial distance R 1 , thereby providing increased binding the further second thread  408  is inserted into the fastener receiving portion of the base member. 
     In addition, the threads may have a substantially triangular cross-sectional shape. Accordingly, due to the increasing extension of the threads from the post, not only does the radial distance increase along the length of threads, but also the height of threads may also increase along the length of threads. For example, as shown in  FIG. 10 , the beginning of second thread  408  may have a first height H 1 . Additionally, third thread  410  may have a second height H 2  at a location that is distal to the location of height H 1  of second thread  408 . First height H 1  may be located closest to fastening end  302  of first cleat member  201 , while second height H 2  may be located closer to ground-engaging end  300  of first cleat member  201 . 
       FIG. 11  illustrates the draft angle of the threads that is produced by the increasing radial distances discussed above. In particular,  FIG. 11  shows a tangent line  500  in alignment with a first radial edge  505  of first thread  406  and second radial edge  510  of second thread  408 . Tangent line  500  may form a draft angle  515  with a longitudinal axis  520  through first cleat member  201 . Draft angle  515  may form a wedge-shape in which the radial edges of the threads are arranged in a conical configuration. 
     Draft angle  515  may have any suitable measurement. In some embodiments, draft angle  515  may be approximately 10 degrees. In other embodiments, draft angle  515  may be between about 5 degrees and about 10 degrees. In other embodiments, draft angle  515  may be less than about 5 degrees. For example, in some embodiments, draft angle  515  may be between approximately 1 degree and approximately 5 degrees. Further in some embodiments, draft angle  515  may be between about 3 degrees and about 5 degrees. 
       FIG. 12  illustrates an exploded view of the cleat system. In particular,  FIG. 12  shows first cleat member  201  in a top perspective view and shows base member  320  in a lower perspective view, such that the cleat system is illustrated in a clam shell like arrangement.  FIG. 12  illustrates several features of first cleat member  201  in more detail. 
     In some embodiments, the threads of the cleat member may include provisions to further increase binding upon insertion into the fastener receiving portion of the base member. For example, in some embodiments, one or more of the faces of the threads may include a texture. For example, in some embodiments, at least one of the threads may include a micro-texture. Micro-texture, or a surface that has been roughened, may assist in providing a tight fit to help prevent unintentional loosening of a cleat member from an article of footwear. 
     Stippled shading on first thread  406 , second thread  408 , and third thread  410  in  FIG. 12  schematically illustrates texture on the surfaces of these threads. The texture may have any suitable surface roughness. The texture may be formed on the surfaces of the threads by any suitable method, such as bead blasting, sand blasting, machining, molding, coatings, or any other suitable technique. 
     In some embodiments, the cleat member may include additional features to provide reinforcement. For example, in some cases, the cleat member may include one or more fin elements extending from the inner wall of the cleat body within the recess around the post. These fin elements may provide reinforcement to the wall of the cleat body. 
     As shown in  FIG. 12 , first cleat member  201  may include at least one fin  342  in recess  318  along angled interior wall  340  of cleat body  304 . In some embodiments, first cleat member  201  may include a plurality of fins  342 , as shown in  FIG. 12 . Fins  342  may have any configuration suitable for reinforcing angled interior wall  340 . For example, as shown in  FIG. 12 , in some embodiments, fins  342  may have a curved turbine-blade type configuration. This configuration may provide reinforcement against the torque applied during installation of first cleat member  201 . 
       FIG. 13  shows a top view of first cleat member  201 .  FIG. 13  illustrates two features discussed above, in greater detail. In particular,  FIG. 13  shows the sweep of the threads, as well as the draft angle. 
     As discussed above, in some embodiments, the cleat member may have a thread that extends partially around the post. For example, at least one thread may extend less than approximately 180 degrees around the post  314 . For example, as shown in  FIG. 13 , in some embodiments, first thread  406 , second thread  408 , and third thread  410  may extend less than approximately 120 degrees around post  314 . Angle dimensions  120  shown in  FIG. 13  illustrate the angular distance between the distal ends of the threads. As shown in  FIG. 13 , in some cases, the distal end of each thread may be located approximately 120 degrees from the proximal end. In some embodiments, at least one thread may extend approximately 180 degrees around post  314 . For example, as illustrated by a dashed line  600 , in some embodiments, the threads may extend approximately 180 degrees around post  314   
     As also discussed above, in some embodiments, the cleat member may include threads that have a draft angle causing the threads to have a different radius at one end of the thread than at the other end of the thread. As shown in  FIG. 13 , first thread  406  may extend from a first proximal end  605  to a first distal end  610 . In addition, third thread  410  may extend from a second proximal end  615  to a second distal end  620 . As shown in  FIG. 13 , first thread  406  may extend a first radial distance R 3  from post  314  at first proximal end  605 . As also shown in  FIG. 13 , third thread  408  may extend a second radial distance R 4  at second distal end  620 . The difference between beginning first radial distance R 3  and second radial distance R 4  is a radial difference D 1 . Due to radial difference D 1 , the draft angle of the threads assists in the tightening of the first cleat member  201  to the article of footwear as it is wedged into a female thread of the base member, causing the female thread to expand against the male thread. 
       FIGS. 14-20  further illustrate the wedging action of the threads due to the increasing thread thickness of the male threads of the cleat member when inserted into the female threads of the base member, which may have a constant thickness. 
       FIG. 14  shows a cross-sectional view of an exemplary embodiment of base member  320 . As shown in  FIG. 14 , base member  320  may include a thread opening  326  that is capable of accepting at least one thread  316  of at least one cleat member  201 . Base member  320  may also include at least one female thread  332  that extends from thread opening  326 . In an exemplary embodiment, female thread  332  may maintain a constant female thread height C 1  along the entire interior of thread  316 , as shown in  FIG. 14 . 
       FIG. 15  shows a cross-sectional view of first cleat member  201 . In this embodiment, only one thread is shown for purposes of illustration. However, it will be understood that first cleat member  201  may include more than one thread as shown in other figures. As discussed above, thread  316  of first cleat member  201  may include proximal end  402  and distal end  404 . Proximal end  402  may be aligned with and inserted into thread opening  326  of base member  320 . As shown in  FIG. 15 , proximal end  402  may include a first thread height H 3  that is less than a second thread height H 4  at distal end  404 . 
     Once proximal end  402  of thread  316  is aligned with thread opening  326  and first cleat member  201  is turned, the increase in thread height of thread  316  helps provide a binding force that wedges the cleat thread into place. 
       FIG. 16  shows a cross-sectional view of an assembled cleat system. As shown in  FIG. 16 , base member  320  is disposed within sole  104  of an article of footwear. In  FIG. 16 , first cleat member  201  is shown fully attached to base member  320 . Accordingly,  FIG. 16  further shows the threads of first cleat member  201  as being fully wedged into the female threads of base member  320  as far as the threads will go with lip  308  of cleat body  304  in contact with ground-facing surface  106  of sole  104 . 
       FIGS. 17 through 19  illustrate different stages of a cleat member interlocking with a base member in a sole. The figures represent the progression of the cleat thread in relation to the female thread of the base member as the cleat member is screwed in place. In  FIG. 17 , fastening portion  310  of first cleat member  201  is shown as being inserted into fastener receiving portion  322  of base member  320 . In the position shown in  FIG. 17 , the threads are aligned and first cleat member  201  turns freely, however, there is little if any binding between the threads. Proximal end  402  of cleat thread  316  is shown extending partially into female thread  332  of base member  320 .  FIG. 17  further shows a dashed reference line  420  illustrating the location of thread  316  upon full engagement with female thread  332 . 
     In  FIG. 18 , first cleat member  201  is shown as having been screwed in part way such that thread  316  begins to bind with female thread  332  of base member  320 . As shown in  FIG. 18 , thread  316  extends further horizontally into female thread  332 , as illustrated by the reduced distance between thread  316  and reference line  420 , which indicates the location of the thread at full engagement. 
       FIG. 19  shows first cleat member  201  fully engaged with base member  320 . In  FIG. 19 , distal end  404  of cleat thread  316  is shown wedged into female thread  332  of base member  320 . First cleat member  201  has been turned approximately one-third of a rotation from initial engagement between cleat thread  316  and female thread  332 . 
     With cleat thread  316  in full engagement with female thread  332 , binding may occur between the surfaces of the threads. For example, as shown in  FIG. 19 , the walls of female thread  332  may be deflected and/or compressed by the surfaces of cleat thread  316 . A dashed line  422  indicates the original, uncompressed location of the wall of female thread  332 . In addition, double lines  650  illustrate the compression of the wall of base member  320 . It will be understood that the amount of compression of the wall is illustrated schematically in  FIG. 19 . As shown in  FIG. 19 , the draft angle of cleat thread  316 , when engaged within the constant profile of the female thread, causes a binding force that wedges the cleat thread  316  into place. 
     The forces that may be produced by the wedging effect of the draft angle of cleat thread  316  are shown in  FIG. 20 . As shown in  FIG. 20 , cleat thread  316  of first cleat member  201  may exert vertical forces on female thread  332  of the base member  320 . These vertical forces are illustrated by arrows  655 . These vertical forces may cause the expansion of female thread  332  by slightly compressing the walls of female thread  332  (see  FIG. 19 ), thus producing additional binding forces that tightly lock the cleat in place. These forces help keep the cleat attached securely to the article of footwear. 
     In some embodiments, the cleat member may include provisions for preventing the introduction of debris between the engagement surfaces of the cleat body and the ground facing surface of the footwear sole. For example, in some embodiments, the seal between the cleat member and the sole may be augmented by deflection of the lip of the cleat body. This is beneficial because debris may wear down thread surfaces, which can decrease the strength and tightness of the hold between the cleat and base member. 
     As shown in  FIG. 20 , lip  308  at the outer periphery of cleat body  304  may be configured to flare outward upon full attachment of first cleat member  201  to base member  320 . For example, as shown in  FIG. 20 , lip  308  may splay radially outward upon engagement with ground-facing surface  106  of sole  104 . This deflection is illustrated by a dashed reference line  660 , which shows the position of the outer surface of lip  308  before such deflection. This deflection provides a tighter seal at the interface between cleat body  304  and ground-facing surface  106  of sole  104 , which may prevent debris from collecting between the threads of first cleat member  201  and base member  320 . In some embodiments, the length of the post and the size/shape of the lip of the cleat body may be designed to enhance this deflection. 
     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.