Patent Description:
<CIT> relates to a sole structure, including multiple macro layers. Each of those macrolayers may include a spring plate and a layer of damping material. Macrolayers may be bonded or otherwise fixed relative to one another and provide constrained layer damping in response to impact forces occurring as a result of activity of a wearer of an article of footwear incorporating the sole structure.

<CIT> relates to a sole unit for footwear, comprising: a medial side, a lateral side, a top surface, and a bottom surface. The sole unit has at least one collapsible profile on a portion of its bottom surface, the collapsible profile being capable of selectively, resiliently canting a side of a user's foot upwardly on the side opposite an applied lateral force during use, the collapsible profile having a canting means for facilitating the selective canting of the user's foot. The invention is also directed to methods of constructing footwear in accordance with the foregoing.

<CIT> describes a traction plate for a shoe. The traction plate is removably attachable to the outsole of a shoe to provide traction on a surface for a shoe wearer. The plate includes a flange with one or more surface-engaging elements on one face. The plate also includes two or more shoe-coupling elements. The shoe-coupling elements are inserted into corresponding receptacles in a shoe-outsole and then rotated to affix the plate to the shoe. The shoe-coupling elements may be captively attached to the plate flange or attachable to the shoe receptacle with a rotation of no more than one full revolution.

<CIT> describes an article of footwear including a sole structure with multiple cleat systems is disclosed. A first cleat system has a first cleat design and one or more cleat member sets that are tuned to provide different levels of traction and flexibility to different regions of the sole structure. A second cleat system has a second cleat design and is disposed on the sole structure in a location to provide maximum traction for various playing surfaces. The sizes, material properties and arrangement of each cleat system are varied.

<CIT> relates to an improved article of footwear, specifically for use in the sport of tennis. The article of footwear addresses motions prevalent in the sport of tennis by enhancing performance and preventing injuries. The article of footwear is asymmetrical and the lateral and medial portions have features to performs different functions to enhance flexibility, balance control, propulsion, stability and support in the specific areas where needed. In part, the medial portion of the article of footwear is designed to provide flexibility while the lateral portion is designed to create stability. These differences in the medial and lateral portions of the article of footwear exist in the upper, e.g., lacing system, material composition, and material thickness differences, and/or in the sole, e.g., different midsole materials, supporting elements effecting only the lateral side.

Thus, according to an aspect, the objective relates to providing an improved ground-engaging component for articles of footwear. This objective is achieved by the subject-matter of the independent claim. Particular embodiments are defined in the dependent claims.

First, some general terminology and information is provided that will assist in understanding various portions of this specification and the invention(s) as described herein. As noted above, the present invention relates to the field of footwear. "Footwear" means any type of wearing apparel for the feet, and this term includes, but is not limited to: all types of shoes, boots, sneakers, sandals, thongs, flip-flops, mules, scuffs, slippers, sport-specific shoes (such as track shoes, golf shoes, tennis shoes, baseball cleats, soccer or football cleats, ski boots, basketball shoes, cross training shoes, etc.), and the like.

<FIG> also provides information that may be useful for explaining and understanding the specification and/or aspects of this invention. More specifically, <FIG> provides a representation of a footwear component <NUM>, which in this illustrated example constitutes a portion of a sole structure for an article of footwear. The same general definitions and terminology described below may apply to footwear in general and/or to other footwear components or portions thereof, such as an upper, a midsole component, an outsole component, a ground-engaging component, etc..

First, as illustrated in <FIG>, the terms "forward" or "forward direction" as used herein, unless otherwise noted or clear from the context, mean toward or in a direction toward a forward-most toe ("FT") area of the footwear structure or component <NUM>. The terms "rearward" or "rearward direction" as used herein, unless otherwise noted or clear from the context, mean toward or in a direction toward a rear-most heel area ("RH") of the footwear structure or component <NUM>. The terms "lateral" or "lateral side" as used herein, unless otherwise noted or clear from the context, mean the outside or "little toe" side of the footwear structure or component <NUM>. The terms "medial" or "medial side" as used herein, unless otherwise noted or clear from the context, mean the inside or "big toe" side of the footwear structure or component <NUM>.

Also, various example features and aspects of this invention may be disclosed or explained herein with reference to a "longitudinal direction" and/or with respect to a "longitudinal length" of a footwear component <NUM> (such as a footwear sole structure). As shown in <FIG>, the "longitudinal direction" is determined as the direction of a line extending from a rear-most heel location (RH in <FIG>) to the forward-most toe location (FT in <FIG>) of the footwear component <NUM> in question (a sole structure or foot-supporting member in this illustrated example). The "longitudinal length" L is the length dimension measured from the rear-most heel location RH to the forward-most toe location FT. The rear-most heel location RH and the forward-most toe location FT may be located by determining the rear heel and forward toe tangent points with respect to front and back parallel vertical planes VP when the component <NUM> (e.g., sole structure or foot-supporting member in this illustrated example, optionally as part of an article of footwear or foot-receiving device) is oriented on a horizontal support surface S in an unloaded condition (e.g., with no weight or force applied to it other than potentially the weight/force of the shoe components with which it is engaged). If the forward-most and/or rear-most locations of a specific footwear component <NUM> constitute a line segment (rather than a tangent point), then the forward-most toe location and/or the rear-most heel location constitute the mid-point of the corresponding line segment. If the forward-most and/or rear-most locations of a specific footwear component <NUM> constitute two or more separated points or line segments, then the forward-most toe location and/or the rear-most heel location constitute the mid-point of a line segment connecting the furthest spaced and separated points and/or furthest spaced and separated end points of the line segments (irrespective of whether the midpoint itself lies on the component <NUM> structure). If the forward-most and/or rear-most locations constitute one or more areas, then the forward-most toe location and/or the rear-most heel location constitute the geographic center of the area or combined areas (irrespective of whether the geographic center itself lies on the component <NUM> structure).

Once the longitudinal direction of a component or structure <NUM> has been determined with the component <NUM> oriented on a horizontal support surface S in an unloaded condition, planes may be oriented perpendicular to this longitudinal direction (e.g., planes running into and out of the page of <FIG>). The locations of these perpendicular planes may be specified based on their positions along the longitudinal length L where the perpendicular plane intersects the longitudinal direction between the rear-most heel location RH and the forward-most toe location FT. In this illustrated example of <FIG>, the rear-most heel location RH is considered as the origin for measurements (or the "<NUM> position") and the forward-most toe location FT is considered the end of the longitudinal length of this component (or the "<NUM> position"). Plane position may be specified based on its location along the longitudinal length L (between <NUM> and <NUM>), measured forward from the rear-most heel RH location in this example, <FIG> shows locations of various planes perpendicular to the longitudinal direction (and oriented in the transverse direction) and located along the longitudinal length L at positions <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> (measured in a forward direction from the rear-most heel location RH). These planes may extend into and out of the page of the paper from the view shown in <FIG>, and similar planes may be oriented at any other desired positions along the longitudinal length L. While these planes may be parallel to the parallel vertical planes VP used to determine the rear-most heel RH and forward-most toe FT locations, this is not a requirement. Rather, the orientations of the perpendicular planes along the longitudinal length L will depend on the orientation of the longitudinal direction, which may or may not be parallel to the horizontal surface S and/or perpendicular to the vertical planes VP in the arrangement/orientation shown in <FIG>.

The following Detailed Description will be better understood when read in conjunction with the accompanying drawings in which like reference numerals refer to the same or similar elements in all of the various views in which that reference number appears.

The reader should understand that the attached drawings are not necessarily drawn to scale.

In the following description of various examples of footwear structures and components, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various example structures and environments in which aspects of the invention may be practiced. It is to be understood that other structures and environments may be utilized and that structural and functional modifications may be made from the specifically described structures and functions without departing from the scope of the present invention which is defined by the appended claims.

While potentially useful for any desired types or styles of shoes, aspects of this invention may be of particular interest for athletic shoes, including track shoes or shoes for short to middle distance runs (e.g., for <NUM>, <NUM>, <NUM>, <NUM>, etc.), e.g., events run on a curved and/or banked track.

Some aspects of this invention relate to ground-engaging components for articles of footwear that include an outer perimeter boundary rim (e.g., at least <NUM> wide (<NUM> inches) or <NUM> wide (<NUM> inches)) that at least partially defines an outer perimeter of the ground-engaging component (e.g., the outer perimeter boundary rim may be present around at least <NUM>%, at least <NUM>% or at least <NUM>% of the outer perimeter of the ground-engaging component), wherein the outer perimeter boundary rim defines an upper-facing surface and a ground-facing surface opposite the upper-facing surface, wherein the outer perimeter boundary rim defines an open space at least at a forefoot support area of the ground-engaging component (and optionally over the arch support and/or heel support areas as well); and a forefoot edge support extending along and defining at least a portion of a first forefoot edge of the ground-engaging component. The forefoot edge support includes a bottom surface that slants in an outward and downward direction over a majority of a width of the bottom surface of the forefoot edge support from a location inside the interior perimeter edge of the outer perimeter boundary rim to the first forefoot edge. The first forefoot edge is an outermost forefoot side edge of the ground-engaging component, wherein the forefoot edge support includes a plurality of edge support components defining a free outer edge of the forefoot edge support. The plurality of edge support components are defined by a plurality of gaps that are located in the bottom surface, the plurality of gaps extending to the outermost forefoot side edge such that the plurality of edge support components and the plurality of gaps together define the outermost forefoot side edge. The forefoot edge support is provided only on a lateral forefoot side edge of the ground-engaging component, or the forefoot edge support is provided only on a medial forefoot side edge of the ground-engaging component. The ground-engaging components for articles of footwear according to the claimed invention further includes a matrix structure (also called a "support structure" herein) extending from the outer perimeter boundary rim (e.g., from the ground-facing surface and/or upper-facing surface) and at least partially across the open space at least at the forefoot support area to define an open cellular construction with plural open cells across the open space at least at the forefoot support area, wherein a plurality (e.g., at least a majority (and in some examples, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, or even at least <NUM>%)) of the open cells of the open cellular construction have curved perimeters with no distinct corners (particularly when viewed from the upper-facing surface).

In at least some example structures in accordance with some examples that help understand the claimed invention, the matrix structure further may define one or more partially open cells located within the open space and/or one or more closed cells (e.g., at the ground-facing surface of the outer perimeter boundary rim). The open space and/or the matrix structure may extend to all areas of the ground-engaging component inside its outer perimeter boundary rim (e.g., from front toe to rear heel, from medial side edge to lateral side edge, etc.). Furthermore, the matrix structure in at least some ground-engaging components in accordance with this invention will define secondary traction elements, e.g., at corners defined by the matrix structure around the open cells, partially open cells, and/or closed cells.

Additionally or alternatively, if desired, the matrix structure may define one or more cleat support areas. In some examples that help understand the invention, the cleat support areas may engage or support primary traction elements, such as track spikes or other cleat elements (e.g., permanently fixed cleats or track spikes, removable cleats or track spikes, etc.). The cleat support area(s) may be located: (a) within the outer perimeter boundary rim (e.g., on its ground-facing surface), (b) at least partially within the outer perimeter boundary rim (e.g., at least partially within its ground-facing surface), (c) within the open space, (d) extending from the outer perimeter boundary rim into and/or across the open space, and/or (e) between a lateral side of the outer perimeter boundary rim and a medial side of the outer perimeter boundary rim. The matrix structure further may define a plurality of secondary traction elements at various locations, e.g., dispersed around one or more of any present cleat support areas; between open and/or partially open cells of the matrix structure; at the outer perimeter boundary rim; at "corners" of the matrix structure; etc. As some more specific examples, the matrix structure may define at least four secondary traction elements dispersed around at least some individual open cells of the open cellular construction that have the curved perimeters with no distinct corners, and optionally, six secondary traction elements may be disposed around at least some of the individual open cells of the open cellular construction that have the curved perimeters with no distinct corners (e.g., in a generally hexagonal arrangement of secondary traction elements). At least some of the plurality of individual open cells that include secondary traction elements dispersed around them may be located at a medial forefoot support area, a central forefoot support area, a lateral forefoot support area, a first metatarsal head support area, a forward toe support area, and/or a heel area of the ground-engaging component.

While primary traction elements may be provided at any desired locations on ground-engaging components in examples that help understand the claimed invention, in some example structures the cleat support areas for primary traction elements will be provided at least at two or more of the following: (a) a first cleat support area (and optionally with an associated primary traction element) at or at least partially in a lateral side of the ground-facing surface of the outer perimeter boundary rim; (b) a second cleat support area (and optionally with an associated primary traction element) at or at least partially in a medial side of the ground-facing surface of the outer perimeter boundary rim; (c) a third cleat support area (and optionally with an associated primary traction element) at or at least partially in a medial side of the ground-facing surface of the outer perimeter boundary rim and located forward of the second cleat support area; and/or (d) a fourth cleat support area (and optionally with an associated primary traction element) at or at least partially in the ground-facing surface of the outer perimeter boundary rim and located forward of at least one of the second or third cleat support areas. All of these four cleat support areas (and/or any associated primary traction element) may be located forward of a perpendicular plane oriented at <NUM> of the ground-engaging component and/or the sole structure. Although some ground-engaging components according to some embodiments of the claimed invention will include only these four cleat support areas (and associated primary traction elements), more or fewer cleat support areas (and primary traction elements associated therewith) may be provided, if desired.

The matrix structure in accordance with the claimed invention includes open cells. In some examples that help understand the claimed invention, the matrix structure may include partially open cells, wherein geographical centers of at least three cells of this first set of "at least partially open cells" are "substantially aligned" or "highly substantially aligned" (the term "at least partially open cells" means one or more of partially open cells and/or open cells, which terms will be explained in more detail below). Optionally, the geographic centers of at least three cells (and in some examples, at least four cells or even at least six cells) of this first set will be "substantially aligned" or "highly substantially aligned," optionally in the forefoot support area, along a line that extends from a rear lateral direction toward a forward medial direction of the ground-engaging component and/or the article of footwear in which it may be contained. Open or partially open cells are considered to be "substantially aligned," as that term is used herein in this context, if the geographical centers of each of the cells in question lie on a straight line and/or within a distance of <NUM> (<NUM> inches) from a straight line. "Highly substantially aligned" cells each have their geographic centers lying on a straight line and/or within a distance of <NUM> (<NUM> inches) from a straight line. Matrix structures in accordance with at least some examples for the understanding of this invention may include two or more sets of open and/or partially open cells, wherein geographical centers of at least three cells within the respective sets are substantially aligned or highly substantially aligned with a straight line for that set (and optionally substantially aligned or highly substantially aligned with a straight line that extends from the rear lateral direction toward the forward medial direction of the ground-engaging component and/or sole structure). Some matrix structures in accordance with some examples for the understanding of this invention may include from <NUM> to <NUM> sets of substantially aligned cells and/or highly substantially aligned cells, or even from <NUM>-<NUM> sets of substantially aligned cells and/or highly substantially aligned cells. When multiple sets of substantially aligned cells and/or highly substantially aligned cells are present in a matrix structure, the aligned and/or highly aligned sets of cells may be separated from one another along the front-to-back and/or longitudinal direction of the ground-engaging component and/or sole structure.

Additional examples that help understand the claimed invention relate to sizes and relative sizes of cells within the support/matrix structure. In general, smaller cells sizes typically will result in more support, more stiffness, and less flexibility than larger cell sizes (e.g., assuming common materials, thicknesses, and/or structures). In at least some examples for the understanding of this invention, an average open cell size defined by the matrix structure on a medial forefoot side support area (and/or on a medial side of a front-to-rear center line) of the ground-engaging component will be smaller than an average open cell size defined by the matrix structure on a lateral forefoot side support area (and/or on a lateral side of the front-to-rear center line) of the ground-engaging component. As another example, an average open cell size defined by the matrix structure in a first metatarsal head support area ("big toe" side support area) of the ground-engaging component will be smaller than an average open cell size defined by the matrix structure in a fourth and/or fifth metatarsal head support area ("little toe" side support area) of the ground-engaging component.

As some additional potential features, in the arch support area and/or the forefoot support area, the matrix structure may define a first open cell and an adjacent second open cell, wherein the first open cell has a cross sectional area (e.g., area of the opening) of less than <NUM>% (and in some examples, less than <NUM>%, less than <NUM>%, or even less than <NUM>%) of a cross sectional area (e.g., area of the opening) of the second open cell, and wherein a geographic center of the first open cell is located closer to the medial side edge of the ground-engaging component than is a geographic center of the second open cell. A cell is "adjacent" to another cell if a straight line can be drawn to connect openings of the two cells without that straight line crossing through the open space of another cell and/or passing between two other adjacent cells and/or if the two cells share a wall. "Adjacent cells" also may be located close to one another (e.g., so that a straight line distance between the openings of cells is less than <NUM> inch (<NUM>) long (and in some examples, less than <NUM> inches long (<NUM>), or even less than <NUM> (<NUM>) inches long)). In these arrangements, the second open cell (the cell further from the medial side) may be elongated in a medial side-to-lateral side direction and/or the first open cell (the cell closer to the medial side) may be elongated in a front-to-rear direction.

In the forefoot support area, such a matrix structure may further define a first open cell, an adjacent second open cell, and an adjacent third open cell, wherein the first open cell has a cross sectional area (e.g., area of the opening) of less than <NUM>% of a cross sectional area (e.g., area of the opening) of the second open cell and/or of less than <NUM>% of a cross sectional area (e.g., area of the opening) of the third open cell. In such an arrangement, a geographic center of the first open cell may be located: (a) closer to the medial side edge than is a geographic center of the second open cell and/or (b) closer to the medial side edge than is a geographic center of the third open cell. If desired, the first open cell may be elongated in a front-to-rear direction.

The forefoot area of some example matrix structures in accordance with embodiments according to the claimed invention further may define a fourth open cell that is adjacent to the third open cell and adjacent a fifth open cell, wherein the fourth open cell has a cross sectional area (e.g., area of the opening) of less than <NUM>% of the cross sectional area (e.g., area of the opening) of the third open cell and/or of less than <NUM>% of a cross sectional area (e.g., area of the opening) of the fifth open cell. In this arrangement, a geographic center of the fourth open cell may be located: (a) closer to the medial side edge than is the geographic center of the third open cell and/or (b) closer to the medial side edge than is a geographic center of the fifth open cell.

As other options, the forefoot area of such a matrix structure further may include a fourth open cell that is adjacent to a fifth open cell and a sixth open cell, wherein the fourth open cell has a cross sectional area (e.g., area of the opening) of less than <NUM>% of the cross sectional area (e.g., area of the opening) of the fifth open cell and/or of less than <NUM>% of a cross sectional area (e.g., area of the opening) of the sixth open cell. In this arrangement, a geographic center of the fourth open cell may be located: (a) closer to the medial side edge than is the geographic center of the fifth open cell and/or (b) closer to the medial side edge than is a geographic center of the sixth open cell. If desired, in this arrangement, the first open cell (described above) may be separated from the fourth open cell by a seventh open cell, and this seventh open cell may be located adjacent to the third open cell and the fifth open cell. Also, if desired, this seventh open cell may have a cross sectional area (e.g., area of the opening) of less than <NUM>% of the cross sectional area (e.g., area of the opening) of the third open cell and/or of less than <NUM>% of a cross sectional area (e.g., area of the opening) of the fifth open cell, and wherein a geographic center of the seventh open cell is located: (a) closer to the medial side edge than is the geographic center of the third open cell and/or (b) closer to the medial side edge than is the geographic center of the fifth open cell.

Additional embodiments not according to the claimed invention relate to ground-engaging components for articles of footwear that include: a foot support member that defines an upper-facing surface and a ground-facing surface opposite the upper-facing surface; and (b) a forefoot edge support engaged with or integrally formed with the foot support member. And an outward slanted bottom surface of the forefoot edge support may originate within <NUM> inches (<NUM>) of the first forefoot edge and slant in an outward and downward direction from its origin toward the first forefoot edge. In some examples of this invention, the forefoot edge support may originate within <NUM> inches (<NUM>) and/or within <NUM> inches (<NUM>) of the first forefoot edge (e.g., measured in the transverse direction at a widest transverse width dimension of the forefoot edge support).

Still the claimed invention relates to ground-engaging components for articles of footwear that include: (a) an outer perimeter boundary rim that at least partially defines an outer perimeter of the ground-engaging component, wherein the outer perimeter boundary rim defines an upper-facing surface and a ground-facing surface opposite the upper-facing surface, and wherein the outer perimeter boundary rim defines an open space at least at a forefoot support area of the ground-engaging component; and (b) a forefoot edge support extending along and defining at least a portion of a first forefoot edge of the ground-engaging component, wherein a bottom surface of the forefoot edge support (which may constitute a bottom, ground-contacting surface of the ground-engaging component) slants in an outward and downward direction from a location adjacent the open space toward and to a location at or adjacent the first forefoot edge. In at least some pairs of sole structures and/or shoes containing the sole structures, the forefoot edge support may be provided only on the lateral forefoot side edge of that shoe, or the forefoot edge support may be provided only on the medial forefoot side edge of that shoe.

In at least some examples for the understanding of the invention, the forefoot edge support may extend downward from the ground-facing surface of the outer perimeter boundary rim. As some more specific examples, the outer perimeter boundary rim may define an exterior perimeter edge and an interior perimeter edge, and the forefoot edge support may originate and/or extend from the open space defined by the outer perimeter boundary rim, e.g., from a location inside the interior perimeter edge of the outer perimeter boundary rim. The forefoot edge support according to the invention extends outward beyond the exterior perimeter edge of the outer perimeter boundary rim. The forefoot edge support may terminate at one end, e.g., at a forward toe location and/or at its other end, e.g., at an arch support area. Each shoe may include a single forefoot edge support of this type, optionally only along one forefoot edge per sole structure (e.g., on the medial forefoot edge of the left shoe and the lateral forefoot edge of the right shoe).

According to the invention, to promote better flexibility and/or natural motion characteristics, the forefoot edge support includes a plurality of edge support components that define a free outer edge of the forefoot edge support. At least some (and optionally all) of these edge support components may extend from (and be interconnected at) a base area (e.g., located at or near the outer perimeter boundary rim) to the free outer edge. At the free outer edge, at least some of the plurality of edge support components may be separated from at least one respective adjacent edge support component by a gap of less than <NUM> (<NUM> inch), less than <NUM> (<NUM> inch), less than <NUM> (<NUM> inch), less than <NUM> (<NUM> inch), and in some examples, by a gap of less than <NUM> (<NUM> inch).

Additional embodiments relate to ground-engaging components that include "directional traction" features that facilitate and better support running around a curve (e.g., a curved (and optionally banked) track). When running a curved track, the runner's inside foot (e.g., left foot when running counter-clockwise) typically is the steering foot and the outside foot (e.g., the right foot when running counterclockwise) is the driving foot. Forces do not act on these two feet in the same manner when running the curve. For example, the inside foot typically changes direction relatively early in the step cycle such that stance and rotation occur off the medial, ball of the foot area (e.g., near the first metatarsal head area). Therefore, in accordance with at least some examples for the understanding of this invention, the ground-engaging component supporting the inside foot includes a single, medial side primary traction element at the medial, ball of the foot area (with other forefoot based primary traction elements provided well forward, e.g., for the toe-off phase of the step cycle), and cells of the ground-engaging component's matrix structure and/or secondary traction elements may be arranged along arcs around this medial, ball of the foot arranged primary traction element. For the outside foot, however, direction change occurs later in the step cycle (e.g., at the terminal stance and/or toe-off phase) such that stance and rotation occur off a medial, forefoot area (e.g., beneath the runner's "big toe"). Therefore, in accordance with at least some examples that help understand the claimed invention, the ground-engaging component supporting the outside foot includes a single, extreme forefoot primary traction element at the medial, toe area (with other forefoot based primary traction elements provided well rearward), and cells of the ground-engaging component's matrix structure and/or secondary traction elements may be arranged along arcs around this extreme forefoot primary element. These different arrangements and orientations of primary traction elements, matrix cells, and secondary traction elements in the right and left ground-engaging component structures help facilitate and support the different rotations and forces applied to the shoe when running a curve (e.g., on a curved or banked track).

Additional aspects of this invention relate to articles of footwear according to the appended claim <NUM>. The sole structures on a pair of shoes need not be mirror images of one another. The upper may be made from any desired upper materials and/or upper constructions, including upper materials and/or upper constructions as are conventionally known and used in the footwear art (e.g., especially upper materials and/or constructions used in track shoes or shoes for short and/or middle distance runs (e.g., for <NUM>, <NUM>, <NUM>, <NUM>, etc.)). As some more specific examples, at least a portion (or even a majority, all, or substantially all) of the upper may include a woven textile component and/or a knitted textile component (and/or other lightweight constructions).

Articles of footwear in accordance with at least some examples for the understanding of the claimed invention will not include an external midsole component (e.g., located outside of the upper). Rather, in at least some examples of this invention, the sole structure will consist essentially of the ground-engaging component, and the article of footwear will consist essentially of an upper (and its one or more component parts, including any laces or other securing system components and/or an interior insole or sock liner component) with the ground-engaging component engaged with it. Some articles of footwear according to aspects of this invention will include the upper-facing surface of the ground-engaging support component directly engaged with the upper (e.g., with a bottom surface of the upper and/or a strobel component). Optionally, the bottom surface of the upper (e.g., a strobel or other bottom upper component) may include a component with desired colors or other graphics to be displayed through the open cells of the matrix structure.

If desired, in accordance with at least some examples for the understanding of the invention, at least some portion(s) of a bottom surface of the upper (e.g., the strobel) may be exposed at an exterior of the shoe structure. As some more specific examples, the bottom surface of the upper may be exposed: (a) in the open space of the ground-engaging component (e.g., at least in the forefoot support area through open cells and/or partially open cells in any present matrix structure, etc.); (b) in the arch support area of the sole structure (e.g., through open cells and/or partially open cells in any present matrix structure, etc.); and/or (c) in the heel support area of the sole structure (e.g., through open cells and/or partially open cells in any present matrix structure, etc.).

More specific examples of structures and aspects of this invention now will be described with reference to the accompanying figures.

<FIG> and <FIG> provide lateral side and bottom views, respectively, of an article of footwear <NUM>. This example article of footwear <NUM> is a track shoe, and more specifically, a track shoe targeted for short or middle distance runs, such as <NUM>, <NUM>, <NUM>, <NUM>, etc. (e.g., races typically run on a curved and/or banked track). Such however, also may be used in shoes for other distance runs and/or other types of uses or athletic activities. The article of footwear <NUM> includes an upper <NUM> and a sole structure <NUM> engaged with the upper <NUM>. The upper <NUM> and sole structure <NUM> may be engaged together in any desired manner, including in manners conventionally known and used in the footwear arts (such as by adhesives or cements, by stitching or sewing, by mechanical connectors, etc.).

The upper <NUM> of this example includes a foot-receiving opening <NUM> that provides access to an interior chamber into which the wearer's foot is inserted. The upper <NUM> further may include a tongue member located across the foot instep area and positioned so as to moderate the feel of the closure system <NUM> (which in this illustrated example constitutes a lace type closure system).

As mentioned above, the upper <NUM> may be made from any desired materials and/or in any desired constructions and/or manners without departing from this invention. As some more specific examples, at least a portion of the upper <NUM> (and optionally a majority, all, or substantially all of the upper <NUM>) may be formed as a woven textile component and/or a knitted textile component. The textile components for upper <NUM> may have structures and/or constructions like those provided in FLYKNIT" brand footwear and/or via FLYWEAVI Tm technology available in products from NIKE, Inc. of Beaverton, OR.

Additionally or alternatively, if desired, the upper <NUM> construction may include uppers having foot securing and engaging structures (e.g., "dynamic" and/or "adaptive fit" structures), e.g., of the types described in <CIT>. As some additional examples, if desired, articles of footwear in accordance with this invention may include foot securing and engaging structures of the types used in FLYWIRE® Brand footwear available from NIKE, Inc. of Beaverton, Oregon. Additionally or alternatively, if desired, articles of footwear in accordance with this invention may include fused layers of upper materials, e.g., uppers of the types included in NIKE's "FUSE" line of footwear products. As still additional examples, uppers of the types described in <CIT> and/or <CIT> may be used without departing from this invention.

The sole structure <NUM> of this example article of footwear <NUM> now will be described in more detail. As shown in <FIG> and <FIG>, the sole structure <NUM> of this example includes one main component, namely a ground-engaging component <NUM>, optionally engaged with the bottom surface <NUM> (e.g., a strobel member) and/or side surface of the upper <NUM> via adhesives or cements, mechanical fasteners, sewing or stitching, etc. The ground-engaging component <NUM> of this example has its rearmost extent 242R located at a rear heel support area.

Notably, in this illustrated example, no external midsole or internal midsole component (e.g., a foam material, a fluid-filled bladder, etc.) is provided. In this manner, the shoe/sole components will absorb little energy from the user when racing, and the vast majority of the force applied to the shoe by the user will be transferred to the contact surface (e.g., the track or ground). If desired, an interior insole component (or sock liner) or an interior midsole component may be provided to at least somewhat enhance the comfort of the shoe. Alternatively, if desired, a midsole component could be provided and located between (a) a bottom surface of the upper <NUM> (e.g., a strobel member) and (b) the ground-engaging component <NUM>. Preferably, the midsole component, if any, will be thin, lightweight component, such as one or more of a foam material, a fluid-filled bladder, etc..

In this illustrated example, a bottom surface <NUM> of the upper <NUM> is exposed at an exterior of the sole structure <NUM> substantially throughout the bottom of the sole structure <NUM> (and exposed over more than <NUM>%, more than <NUM>%, and even more than <NUM>% of the bottom surface area of the sole structure <NUM>). As shown in <FIG>, the bottom surface <NUM> of the upper <NUM> is exposed at the forefoot support area, the arch support area, and/or the heel support area (through open cells <NUM> or any partially open cells <NUM> of the ground-engaging component <NUM> (also called the "open space" <NUM> herein) described in more detail below).

Example ground-engaging components <NUM> for sole structures <NUM>/articles of footwear <NUM> in accordance with examples of this invention now will be described in more detail with reference to <FIG>. As shown, these example ground-engaging components <NUM> include an outer perimeter boundary rim <NUM>, for example, that may be at least <NUM> (<NUM> inches) wide (and in some examples, is at least <NUM> (<NUM> inches) wide, at least <NUM> (<NUM> inches) wide, or even at least <NUM> (<NUM> inches) wide). This "width" Wo is defined as the direct, shortest distance from one (e.g., exterior) edge of the outer perimeter boundary rim 242O to its opposite (e.g., interior) edge by the open space <NUM>, as shown in <FIG>. While <FIG> shows this outer perimeter boundary rim 242O extending completely and continuously around and defining <NUM>% of an outer perimeter of the ground-engaging component <NUM>, other options are possible. For example, if desired, there may be one or more breaks in the outer perimeter boundary rim 242O at the outer perimeter of the ground-engaging component <NUM> such that the outer perimeter boundary rim 242O is present around only at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, or even at least <NUM>% of the outer perimeter of the ground-engaging component <NUM>. The outer perimeter boundary rim 242O may have a constant or changing width Wo over the course of its perimeter. The outer perimeter boundary rim 242O also may extend to define the outer edge of the sole structure <NUM>.

<FIG> further shows that the outer perimeter boundary rim 242O of the ground-engaging component <NUM> defines an open space <NUM> at least at a forefoot support area of the ground-engaging component <NUM>, and in this illustrated example, the open space <NUM> extends into the arch support area and the heel support area of the ground-engaging component <NUM>. The rearmost extent 242R of the outer perimeter boundary rim 242O of this example is located within the heel support area, and optionally at a rear heel support area of the ground-engaging component <NUM>. The ground-engaging component <NUM> may fit and be fixed to a bottom surface <NUM> and/or side surface of the upper <NUM>, e.g., by cements or adhesives, etc..

The ground-engaging components <NUM> of this example are shaped so as to extend completely across the forefoot support area of the sole structure <NUM> from the lateral side to the medial side. In this manner, the outer perimeter boundary rim 242O forms the medial and lateral side edges of the bottom of the sole structure <NUM> at least at the forefoot medial and forefoot lateral sides and around the front toe area. The ground-engaging component <NUM> also may extend completely across the sole structure <NUM> from the lateral side edge to the medial side edge at other areas of the sole structure <NUM>, including throughout the longitudinal length of the sole structure <NUM>. In this manner, the outer perimeter boundary rim 242O may form the medial and lateral side edges of the bottom of the sole structure <NUM> throughout the sole structure <NUM>, if desired.

The outer perimeter boundary rim 242O of this illustrated example ground-engaging component <NUM> defines an upper-facing surface 248U (e.g., see <FIG>, <FIG>, and <FIG>) and a ground-facing surface <NUM> (e.g., as shown in <FIG> and <FIG>) opposite the upper-facing surface 248U. The upper-facing surface 248U provides a surface (e.g., a smooth and/or contoured surface) for supporting the wearer's foot and/or engaging the upper <NUM> (and/or optionally engaging any present midsole component). The outer perimeter boundary rim 242O may provide a relatively large surface area for securely supporting a plantar surface of a wearer's foot. Further, the outer perimeter boundary rim 242O may provide a relatively large surface area for securely engaging another footwear component (such as the bottom surface <NUM> of the upper <NUM>), e.g., a surface for bonding via adhesives or cements, for supporting stitches or sewn seams, for supporting mechanical fasteners, etc..

<FIG>, <FIG>, <FIG>, and <FIG> further illustrate that the ground-engaging component <NUM> of this example sole structure <NUM> includes a support structure <NUM> that extends from the outer perimeter boundary rim 242O into and at least partially across (and optionally completely across) the open space <NUM>. The top surface of this example support structure <NUM> at locations within the open space <NUM> lies flush with and/or smoothly transitions or morphs into the outer perimeter boundary rim 242O to provide a portion of the upper-facing surface 248U (and may be used for the purposes of the upper-facing surface 248U as described above).

The support structure <NUM> of these examples extends from the ground-facing surface <NUM> of the outer perimeter boundary rim 242O to define at least a portion of the ground-facing surface <NUM> of the ground-engaging component <NUM>. In the illustrated examples of <FIG> and <FIG>, the support structure <NUM> includes a matrix structure (also labeled <NUM> herein) extending from the ground-facing surface <NUM> of the outer perimeter boundary rim 242O and into, partially across, or fully across the open space <NUM> to define a cellular construction. The illustrated matrix structure <NUM> defines at least one of: (a) one or more open cells located within the open space <NUM>, (b) one or more partially open cells located within the open space <NUM>, and/or (c) one or more closed cells, e.g., located beneath the outer perimeter boundary rim 242O and/or primary cleat support area. An "open cell" constitutes a cell in which the perimeter of the cell opening is defined completely by the matrix structure <NUM> (note, for example, cells <NUM> in <FIG>). A "partially open cell" constitutes a cell in which one or more portions of the perimeter of the cell opening are defined by the matrix structure <NUM> within the open space <NUM> and one or more other portions of the perimeter of the cell opening are defined by another structure, such as the outer perimeter boundary rim 242O (note, for example, cells <NUM> in <FIG>) and/or a forefoot edge support (described in more detail below). A "closed cell" may have the outer matrix structure <NUM> (e.g., at the ground-facing surface <NUM>) but no opening (e.g., the cell may be formed such that the portion of the matrix <NUM> that would define the cell opening is located under the outer perimeter boundary rim 242O and/or is covered by the forefoot edge support). As shown in <FIG>, in this illustrated example matrix structure <NUM>, the openings of at least <NUM>% of the open cells <NUM> and/or partially open cells <NUM> of the open cellular construction (and optionally, at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, or even at least <NUM>%) have openings with curved perimeters and no distinct corners (e.g., round, elliptical, and/or oval shaped, e.g., as viewed at least from the upper-facing surface 248U). The open space <NUM> and/or matrix structure <NUM> may extend to all areas of the ground-engaging component <NUM> within the outer perimeter boundary rim <NUM>.

As further shown in <FIG> and <FIG>, the matrix structure <NUM> further defines one or more primary traction element or cleat support areas <NUM>. Four separate cleat support areas <NUM> are shown in the examples of <FIG>, with: (a) three primary cleat support areas <NUM> on the medial side of the ground-engaging component <NUM> (one at or near a medial forefoot support area or a medial midfoot support area of the ground-engaging component <NUM>, one forward of that one in the medial forefoot support area, and one forward of that one at the medial toe support area) and (b) one primary cleat support area <NUM> on the lateral side of the ground-engaging component <NUM> (at or near a lateral forefoot support area or a lateral midfoot support area of the ground-engaging component <NUM>). Primary traction elements, such as track spikes <NUM> or other cleats, may be engaged or integrally formed with the ground-engaging component <NUM> at the cleat support areas <NUM> (e.g., with one cleat or track spike <NUM> provided per cleat support area <NUM>). The cleats or track spikes <NUM> (also called "primary traction elements" herein) may be permanently fixed at cleat mount areas in their associated cleat support areas <NUM>, such as by in-molding the cleats or track spikes <NUM> into the cleat support areas <NUM> when the matrix structure <NUM> is formed (e.g., by molding). In such structures, the cleat or track spike <NUM> may include a disk or outer perimeter member that is embedded in the material of the cleat support area <NUM> during the molding process. As another alternative, the cleats or track spikes <NUM> may be removably mounted to the ground-engaging component <NUM> at cleat mount areas, e.g., by a threaded type connector, a turnbuckle type connector, or other removable cleat/spike structures as are known and used in the footwear arts. Hardware or other structures for mounting the removable cleats may be integrally formed in the cleat support area <NUM> or otherwise engaged in the cleat support area <NUM> (e.g., by in-molding, adhesives, or mechanical connectors).

The cleat support areas <NUM> can take on various structures without departing from this invention. In the illustrated example, the cleat support areas <NUM> are defined by and as part of the matrix structure <NUM> as a thicker portion of matrix material located within or partially within the outer perimeter boundary rim 242O and/or located within the open space <NUM>. As various options, if desired, one or more of the cleat support areas <NUM> may be defined in one or more of the following areas: (a) solely in the outer perimeter boundary rim 242O, (b) partially in the outer perimeter boundary rim 242O and partially in the open space <NUM>, and/or (c) completely within the open space <NUM> (and optionally located at or adjacent the outer perimeter boundary rim 242O). When multiple cleat support areas <NUM> are present in a single ground-engaging component <NUM>, all of the cleat support areas <NUM> need not have the same size, construction, and/or orientation with respect to the outer perimeter boundary rim 242O and/or open space <NUM> (although they all may have the same size, construction, and/or orientation, if desired).

While other constructions are possible, in this illustrated example (e.g., see <FIG>), the cleat support areas <NUM> are formed as generally hexagonal shaped areas of thicker material into which or at which at least a portion of the cleat/spike <NUM> and/or mounting hardware will be fixed or otherwise engaged. The cleat support areas <NUM> are integrally formed as part of the matrix structure <NUM> in this illustrated example. The illustrated example further shows that the matrix structure <NUM> defines a plurality of secondary traction elements <NUM> dispersed around the cleat support areas <NUM>. While other options and numbers of secondary traction elements <NUM> are possible, in this illustrated example, a secondary traction element <NUM> is provided at each of the six corners of the generally hexagonal structure making up the cleat support area <NUM> (such that each cleat support area <NUM> has six secondary traction elements <NUM> dispersed immediately around it). The secondary traction elements <NUM> of this example are raised, sharp points or pyramid type structures made of the matrix <NUM> material and raised above a base surface <NUM> of the generally hexagonal cleat support area <NUM> (and may have a structure like those described below in conjunction with <FIG>). The free ends of the primary traction elements <NUM> extend beyond the free ends of the secondary traction elements <NUM> (in the cleat extension direction and/or when the shoe <NUM> is positioned on a flat surface) and are designed to engage the ground first. Note <FIG> and <FIG>. If the primary traction elements <NUM> sink a sufficient depth into the contact surface (e.g., a track, the ground, etc.), the secondary traction elements <NUM> then may engage the contact surface and provide additional traction to the wearer. In an individual cleat mount area <NUM> around a single primary traction element <NUM>, the points or peaks of the immediately surrounding secondary traction elements <NUM> that surround that primary traction element <NUM> may be located within <NUM> inches (<NUM>) (and in some examples, within <NUM> inch (<NUM>) or even within <NUM> inch (<NUM>)) of the peak or point of the surrounded primary traction element <NUM> in that mount area <NUM>.

In at least some examples of this invention, the outer perimeter boundary rim 242O and the support/matrix structure <NUM> extending into/across the open space <NUM> may constitute an unitary, one-piece construction. The one-piece construction can be formed from a polymeric material, such as a PEBAX® brand polymer material or a thermoplastic polyurethane material. As another example, if desired, the ground-engaging component <NUM> may be made as multiple parts (e.g., split at the forward-most toe area, split along the front-to-back direction, and/or split or separated at other areas), wherein each part includes one or more of: at least a portion of the outer perimeter boundary rim 242O and at least a portion of the support/matrix structure <NUM>. As another option, if desired, rather than an unitary, one-piece construction, one or more of the outer perimeter boundary rim 242O and the support/matrix structure <NUM> individually may be made of two or more parts. The material of the matrix structure <NUM> and/or ground-engaging component <NUM> in general may be relatively stiff, hard, and/or resilient so that when the ground-engaging component <NUM> flexes in use (e.g., when sprinting or running fast), the material tends to return (e.g., spring) the component <NUM> back to or toward its original shape and structure when the force is removed or sufficiently relaxed (and optionally return energy to the wearer's foot), e.g., as occurs during a step cycle when the foot is lifting off the ground.

Optionally, the outer perimeter boundary rim 242O and the support structure <NUM>, whether made from one part or more, will have a combined mass of less than <NUM> grams (exclusive of any separate primary traction elements, like spikes <NUM>, and/or primary traction element mounting hardware), and in some examples, a combined mass of less than <NUM> grams, less than <NUM> grams, less than <NUM> grams, or even less than <NUM> grams. The entire ground-engaging component <NUM> also may have any of these weighting characteristics.

<FIG> are provided to illustrate additional features that may be present in ground-engaging components <NUM> and/or articles of footwear <NUM> in accordance with at least some aspects of this invention. <FIG> is a view similar to that of <FIG> with the rear heel RH and forward toe FT locations of the sole structure <NUM> identified and the longitudinal length L and direction identified. Planes perpendicular to the longitudinal direction (and going into and out of the page) are shown, and the locations of various footwear <NUM> and/or ground-engaging component <NUM> features are described with respect to the locations of these planes. For example, <FIG> illustrates that the rear-most extent 242R of the ground-engaging component <NUM> is located at <NUM>. In some examples of this invention, however, this rear-most extent 242R of the ground-engaging component <NUM> may be located within a range of <NUM> and <NUM> with respect to the shoe's and/or sole structure's overall longitudinal length L, and in some examples, within a range of <NUM> to <NUM> or even <NUM> to <NUM> based on the overall shoe's and/or overall sole structure's longitudinal length L.

Potential primary traction element attachment locations for the four illustrated primary traction elements <NUM> are described in the following table (with the "locations" being measured from a center location (or point) of the ground-contacting portion of the cleat/spike <NUM> and being measured with respect to the longitudinal length(s) of the sole structure <NUM> and/or the footwear structure <NUM>):.

Notably, in this illustrated example, the only lateral side primary cleat element <NUM> (or at least the only lateral side forefoot primary cleat element <NUM>) is located further rearward than all of the medial side primary cleat elements (or at least rearward of all medial side forefoot primary cleat elements <NUM>). If desired, however, one or more additional primary traction elements <NUM> can be provided at other locations of the ground-engaging component <NUM> structure, including rearward of either or both of the identified rear cleats, between the identified medial cleats, forward of either or both of the forward-most cleats, and/or between the lateral and medial cleats (e.g., in the matrix structure <NUM> within the open area <NUM>, at a central forward toe location, etc.).

<FIG> further illustrates that the forward-most extent of the outer perimeter boundary rim 242O is located at <NUM> (at the forward-most toe location FT). This forward-most extent of the outer perimeter boundary rim <NUM>, however, may be located at other places, if desired, such as within a range of <NUM> and <NUM>, and in some examples, within a range of <NUM> to <NUM> or even <NUM> to <NUM>, based on the shoe structure's overall longitudinal length.

<FIG> further illustrates that in this example ground-engaging component structure <NUM>, some cells of the matrix structure <NUM> are generally formed in lines or along curves that extend across the ground-engaging component <NUM> and the sole structure <NUM>. The term "cells" used in this context is used generically to refer to any one or more of open cells <NUM>, partially open cells <NUM>, and/or closed cells (e.g., cells completely formed by the matrix structure <NUM> and closed off within the outer perimeter boundary rim 242O) in any numbers or combinations. In some example structures <NUM> for the understanding of the invention, from <NUM> to <NUM> "lines" or "curves" of adjacent cells may be formed in the ground-engaging element structure <NUM> (and in some examples, from <NUM>-<NUM> lines or curves of adjacent cells or even from <NUM>-<NUM> lines or curves of this type). Each "line" or "curve" of adjacent cells extending in the generally medial-to-lateral side direction may contain from <NUM> to <NUM> cells, and in some examples, from <NUM> to <NUM> cells or from <NUM>-<NUM> cells.

More specifically, and referring to <FIG> (which is a view similar to <FIG>), the ground-facing surface <NUM> of the ground-engaging component <NUM> is shown with additional lines to highlight certain cell features that may be present in at least some example structures for the understanding the invention. For example, this illustrated matrix structure <NUM> defines several sets of at least partially open cells (meaning open cells <NUM> and/or partially open cells <NUM>), wherein geographical centers of at least three cells of these sets of at least partially open cells are substantially aligned or highly substantially aligned. Examples of these "sets" of "aligned" cells are shown in <FIG> at alignment lines 400A-<NUM> Notably, while not a requirement for any or all "sets" of three or more aligned cells, at least the "alignment lines" 400A-400F shown in this illustrated example extend from a rear lateral direction toward a forward medial direction of the ground-engaging component <NUM> and/or the sole structure <NUM> (and not necessarily in the direct transverse direction). If desired, any one or more sets of cells may be substantially aligned along a line that extends from the rear lateral direction toward the forward medial direction of the ground-engaging component <NUM> and/or sole structure <NUM>. These sets of "substantially aligned" or "highly substantially aligned" cells can help provide more natural flexion and motion for the foot, e.g., as the person's weight rolls forward in a direction from the heel to the toe and/or from the midfoot to the toe during a step cycle. For example, the substantially aligned or highly substantially aligned open spaces <NUM> along lines 400A-400F (as well as lines <NUM>-400I) provide and help define lines of flex that extend at least partially across the sole structure <NUM> and/or the ground-engaging component <NUM> from the lateral side to the medial side direction and help the ground-engaging component <NUM> bend with the foot as the wearer rolls the foot forward for the toe-off phase of a step cycle.

<FIG> further shows sets of adjacent cells located along one or more lines or curves 402A-402D that extend in the generally forward-to-rear direction of the ground-engaging component <NUM> and/or sole structure <NUM>. One or more of the lines or curves 402A-402D may be oriented so that their concave surface (if any) faces the medial side of the ground-engaging component <NUM> and/or sole structure <NUM> and so that their convex surface (if any) faces the lateral side of the ground-engaging component <NUM> and/or sole structure <NUM>. The curve(s) (e.g., 402A, 402B) may be generally gently and smoothly curved (e.g., arcs of a circle) or relatively linear. While four generally front-to-back sets of adjacent at least partially open cells are shown as lines or curves 402A-402D in <FIG>, more or fewer sets could be provided, if desired. As a more specific example, from one to eight linear or curved sets of adjacent at least partially open cells 402A-402D could be provided across the ground-engaging component <NUM> and/or sole structure <NUM>, and each of these sets of cells 402A-402D may include from <NUM>-<NUM> cells, and in some examples, from <NUM>-<NUM> cells, or from <NUM>-<NUM> cells in the forefoot area. These sets of adjacent at least partially open cells 402A-402D also can help provide more natural flexion and motion for the foot as the person's weight rolls forward from the heel and/or midfoot to the toe and from the lateral side to the medial side during a step cycle. For example, adjacent open spaces <NUM> along lines or curves 402A-402D provide and help define lines or curves of flex that extend across the foot from the rear-to-front direction and help the ground-engaging component <NUM> bend along a front-to-back line or curve with the foot as the wearer rolls the foot from the lateral side to the medial side for the toe-off phase of a step cycle.

As shown by <FIG> and <FIG>, in these illustrated example ground-engaging components <NUM>, an average open cell <NUM> size defined by the matrix structure <NUM> on a medial forefoot side support area of the ground-engaging component <NUM> is smaller than an average open cell <NUM> size defined by the matrix structure <NUM> on a lateral forefoot side support area of the ground-engaging component <NUM>. Compare, for example: (a) the areas of the open cells (e.g., cell opening area) along line/curve 402C and those toward the medial side with (b) the areas of the open cells (e.g., cell opening area) along curve 402B and those toward the lateral side. Also, as further shown in these figures, an average open cell <NUM> size defined by the matrix structure <NUM> in a first metatarsal head support area ("big toe" side) of the ground-engaging component <NUM> is smaller than an average open cell <NUM> size defined by the matrix structure <NUM> in a fourth and/or fifth metatarsal head support area ("little toe" side) of the ground-engaging component <NUM>. The smaller open cells <NUM> at the first metatarsal head support area provide somewhat greater stiffness and support, e.g., to receive force/weight during the toe-off or push-off phase of a step cycle.

Also, in this same vein, if desired, the matrix structure <NUM> may define open cell <NUM> sizes such that an average open cell size (e.g., cell opening area) defined by the matrix structure <NUM> on a medial side of a longitudinal center line of the ground-engaging component <NUM> and/or sole structure <NUM>, at least at the forefoot support area, is smaller than an average open cell size (e.g., cell opening area) defined by the matrix structure <NUM> on a lateral side of the longitudinal center line, again, at least at the forefoot support area. The "longitudinal center line" of a ground-engaging component <NUM> and/or a sole structure <NUM> can be found by locating the center points of line segments extending in the transverse direction (see <FIG>) from the lateral side edge to the medial side edge of the ground-engaging component <NUM> and/or the sole structure <NUM> all along the longitudinal length of the component <NUM>/sole structure <NUM>.

Additional potential features of various specific areas of the ground-engaging component <NUM> now will be described in more detail. As shown in <FIG>, in the forefoot support area, the matrix structure <NUM> of this example defines a first open cell (e.g., 252A) and an adjacent second open cell (252B) in which the first open cell 252A has a cross sectional area (area of the opening) of less than <NUM>% (and in some adjacent cell pairs, less than <NUM>% or even less than <NUM>%) of a cross sectional area (area of the opening) of the second open cell 252B. Further, a geographic center of the first (smaller) open cell 252A is located closer to the medial side edge <NUM> than is a geographic center of the second (larger) open cell 252B. As shown in <FIG>, the first (smaller) open cell 252A is elongated in a front-to-rear direction. Also, while not shown in specifically identified cells in <FIG>, the second (larger) open cell 252B may be elongated in a medial side-to-lateral side direction, if desired. The matrix structure <NUM> of <FIG> includes additional adjacent cell pairs or sets (e.g., 252C, 252D, and 252E) having one or more of the same relative size and/or location characteristics of adjacent cell pair 252A/252B described above. Also, if desired, the adjacent cell pairs or sets (e.g., 252A/B, 252C, 252D, 252E) may lie adjacent one another (e.g., with the smaller cells of the pair or sets (closer to the medial side edge <NUM>) adjacent one another moving in the front-to-back direction and the larger cells of the pair or sets (further from the medial side edge <NUM>) adjacent one another moving in the front-to-back direction.

As further shown with respect to the open cells labeled 252A-252E in <FIG>, the larger and smaller open cells may be arranged adjacent one another in generally triangular arrangements and/or such that some open cells <NUM> (or other cells) will have six cells around and adjacent to them. More specifically, the cells 252A-252E (and others) are arranged such that two smaller, adjacent (and closer to the medial side edge <NUM>) open cells are located adjacent one larger open cell (which is located further from the medial side edge <NUM> than the two smaller adjacent open cells). Likewise, two larger, adjacent (and further from the medial side edge <NUM>) open cells are located adjacent one smaller open cell (which is located closer the medial side edge <NUM> than the two larger adjacent open cells). Thus, two of the smaller open cells and one larger open cell are located in a generally triangular arrangement and two larger open cells and one smaller open cell are located in a generally triangular arrangement. This generally triangular arrangement may be repeated one or more times in the forefoot matrix structure area.

<FIG> are provided to help illustrate potential features of the matrix structure <NUM> and the various cells described above. <FIG> provides an enlarged top view showing the upper-facing surface 248U at an area around an open cell <NUM> defined by the matrix structure <NUM> (the open space is shown at <NUM>). <FIG> shows an enlarged bottom view of this same area of the matrix structure <NUM> (showing the ground-facing surface <NUM>). <FIG> shows a side view at one leg <NUM> of the matrix structure <NUM>, and <FIG> shows a cross-sectional and partial perspective view of this same leg <NUM> area. As shown in these figures, the matrix structure <NUM> provides a smooth top (upper-facing) surface 248U but a more angular ground-facing surface <NUM>. More specifically, at the ground-facing surface <NUM>, the matrix structure <NUM> defines a generally hexagonal ridge <NUM> around the open cell <NUM>, with the corners 504C of the hexagonal ridge <NUM> located at a junction area between three adjacent cells in a generally triangular arrangement (the junction of the open cell <NUM> and two adjacent cells 252J, which may be open, partially open, and/or closed cells, in this illustrated example).

As further shown in these figures, along with <FIG> (which shows a sectional view along line 5E-5E of <FIG>), the side walls <NUM> between the upper-facing surface 248U at cell perimeter 244P and the ground-facing surface <NUM>, which ends at ridge <NUM> in this example, are sloped and/or curved. Thus, the overall matrix structure <NUM>, at least at some locations between the generally hexagonal ridge <NUM> corners 504C, may have a triangular or generally triangular shaped cross section (e.g., see <FIG>). Moreover, as shown in <FIG> and SD, the generally hexagonal ridge <NUM> may be sloped or curved from one corner 504C to the adjacent corners 504C (e.g., with a local maxima point P located between adjacent corners 504C). The side walls <NUM> may have a planar surface (e.g., like shown in <FIG>), a partially planar surface (e.g., planar along some of its height/thickness dimension Z), a curved surface (e.g., a concave surface as shown in <FIG>), or a partially curved surface (e.g., curved along some of its height dimension Z).

The raised corners 504C of the generally hexagonal ridge <NUM> in this illustrated example ground-engaging component <NUM> may be formed as sharp peaks that may act as secondary traction elements at desired locations around the ground-engaging component <NUM>. As evident from these figures and the discussion above, the generally hexagonal ridges <NUM> and side walls <NUM> from three adjacent cells (e.g., <NUM> and two 252J cells) meet at a single (optionally raised) corner 504C and thus may form a substantially pyramid type structure (e.g., a pyramid having three side walls 252F, <NUM> that meet at a point 504C). This substantially pyramid type structure can have a sharp point (e.g., depending on the slopes of walls 252F, <NUM>), which can function as a secondary traction element when it contacts the ground in use. This same type of pyramid structure formed by matrix <NUM> also may be used to form the secondary traction elements <NUM> at cleat support areas <NUM> and/or around closed cells (e.g., beneath the outer perimeter boundary rim <NUM>).

Not every cell (open, partially open, or closed) in the ground-engaging component <NUM> needs to have this type of secondary traction element structure (e.g., with raised pointed pyramids at the generally hexagonal ridge <NUM> corners 504C), and in fact, not every generally hexagonal ridge <NUM> corner 504C around a single cell <NUM> needs to have a raised secondary traction element structure. One or more of the ridge components <NUM> of a given cell <NUM> may have a generally straight line structure along the ground-facing surface <NUM> and/or optionally a linear or curved structure that moves closer to the upper-facing surface 248U moving from one corner 504C to an adjacent corner 504C. In this manner, secondary traction elements may be placed at desired locations around the ground-engaging element <NUM> structure and left out (e.g., with smooth corners 504C and/or edges in the z-direction) at other desired locations. Additionally or alternatively, if desired, raised points and/or other secondary traction elements could be provided at other locations on the matrix structure <NUM>, e.g., anywhere along ridge <NUM> or between adjacent cells. As some more specific examples, a portion of the arch support area (e.g., area <NUM> in <FIG>) may have no or fewer prominent secondary traction elements (e.g., smoother matrix <NUM> walls), while other areas (e.g., the heel support area <NUM>, the forefoot area <NUM> (e.g., including one or more of the forward toe area, the lateral forefoot side support area, the medial forefoot side support area, and/or the central forefoot support area, including areas beneath at least some of the metatarsal head support areas) may include the secondary traction elements (or more pronounced secondary traction elements).

Notably, in this example construction, the matrix structure <NUM> defines at least some of the cells <NUM> (and 252J) such that the perimeter of the entrance to the cell opening <NUM> around the upper-facing surface 248U (e.g., defined by perimeter 244P of the ovoid shaped opening) is smaller than the perimeter of the entrance to the cell opening <NUM> around the ground-facing surface <NUM> (e.g., defined by the generally hexagonal perimeter ridge <NUM>). Stated another way, the area of the entrance to the cell opening <NUM> from the upper-facing surface 248U (e.g., the area within and defined by the perimeter 244P of the ovoid shaped opening) is smaller than the area of the entrance to the cell opening <NUM> from the ground-facing surface <NUM> (e.g., the area within and defined by the generally hexagonal perimeter ridge <NUM>). The generally hexagonal perimeter ridge <NUM> completely surrounds the perimeter 244P in at least some cells. These differences in the entrance areas and sizes are due to the sloped/curved sides walls <NUM> from the upper-facing surface 248U to the ground-facing surface <NUM> as shown in <FIG>, and <FIG>.

<FIG> show views similar to those in <FIG>, respectively, but with a portion of the matrix structure <NUM> originating in the outer perimeter boundary rim 242O (and thus the cell is a partially open cell <NUM>). As shown in <FIG>, in this illustrated example, the matrix structure <NUM> morphs outward and downward from the ground-facing surface <NUM> of the outer perimeter boundary rim 242O. This may be accomplished, for example, by molding the matrix structure <NUM> as an unitary, one-piece component with the outer perimeter boundary rim member 242O. Alternatively, the matrix structure <NUM> could be formed as a separate component that is fixed to the outer perimeter boundary rim member <NUM>, e.g., by cements or adhesives, by mechanical connectors, etc. As another option, the matrix structure <NUM> may be made as an unitary, one-piece component with the outer perimeter boundary rim member 242O by rapid manufacturing techniques, including rapid manufacturing additive fabrication techniques (e.g., 3D printing, laser sintering, etc.) or rapid manufacturing subtractive fabrication techniques (e.g., laser ablation, etc.). The structures and various parts shown in Figs. SF-<NUM> may have any one or more of the various characteristics, options, and/or features of the similar structures and parts shown in <FIG> (and like reference numbers in these figures represent the same or similar parts to those used in other figures).

<FIG> provide various views of another example sole structure <NUM> for an article of footwear in accordance with some examples of this invention. This example sole structure <NUM> may be used in articles of footwear, such as track shoes targeted for short or middle distance runs, such as <NUM>, <NUM>, <NUM>, <NUM>, etc., including shoes for use on a curved and/or banked track. The sole structure <NUM> may be used with any desired type of upper and/or overall shoe construction, including shoe constructions and/or uppers having any of the constructions and/or upper <NUM> features described above in conjunction with the shoe <NUM> of <FIG>.

The sole structure <NUM> of this example now will be described in more detail. As shown in <FIG>, the sole structure <NUM> of this example includes one main component, namely a ground-engaging component <NUM>, that optionally may be engaged with a bottom surface (e.g., a strobel member) and/or side surface of an upper (e.g., like bottom surface <NUM> and upper <NUM>) via adhesives or cements, mechanical fasteners, sewing or stitching, etc. The ground-engaging component <NUM> of this example has its rearmost extent 642R located at a rear heel support area and its forward most extent 642T at the forward toe support area.

Like the structures described above, if desired, utilizing this example ground-engaging component <NUM>, no external midsole or internal midsole component (e.g., a foam material, a fluid-filled bladder, etc.) need be provided in the article of footwear. In this manner, the shoe/sole components will absorb little energy from the user when racing, and the vast majority of the force applied to the shoe by the user will be transferred to the contact surface (e.g., the track or ground) and returned to the user's foot. If desired, an interior insole component (or sock liner) and/or interior midsole component may be provided to at least somewhat enhance the comfort of the shoe. Alternatively, if desired, a midsole component could be provided and located between (a) a bottom surface of the upper (e.g., a strobel member) and (b) the ground-engaging component <NUM>. Preferably, the midsole component, if any, will be thin, lightweight component, such as one or more of a foam material, a fluid-filled bladder, etc..

Also, in this illustrated example ground-engaging component <NUM>, a bottom surface of the upper may be exposed at an exterior of the sole structure <NUM> substantially throughout the bottom of the sole structure <NUM> (and exposed over more than <NUM>%, more than <NUM>%, and even more than <NUM>% of the bottom surface area of the sole structure <NUM>). Like the example shown in <FIG>, the bottom surface of the upper may be exposed at the forefoot support area, the arch support area, and/or the heel support area (through open cells <NUM> or any partially open cells <NUM> of the ground-engaging component <NUM>).

Features of this example ground-engaging component <NUM> for sole structures <NUM> now will be described in more detail with reference to <FIG>. As shown, this example ground-engaging component <NUM> includes an outer perimeter boundary rim 642O, for example, that may be at least <NUM> (<NUM> inches) wide (and in some examples, is at least <NUM> (<NUM> inches) wide, at least <NUM> (<NUM> inches) wide, or even at least <NUM> (<NUM> inches) wide). This "width," as described above with respect to <FIG>, is defined as the direct, shortest distance from one (e.g., exterior) edge of the outer perimeter boundary rim 642O to its opposite (e.g., interior) edge by the open space <NUM>, as shown in <FIG>. While <FIG> and <FIG> show this outer perimeter boundary rim 642O extending completely and continuously around the ground-engaging component <NUM>, other options are possible. For example, if desired, there may be one or more breaks in the outer perimeter boundary rim 642O at the outer perimeter of the ground-engaging component <NUM> such that the outer perimeter boundary rim 642O is present around only at least <NUM>%, at least <NUM>%, at least <NUM>%, at least <NUM>%, or even at least <NUM>% of the outer perimeter of the ground-engaging component <NUM>. The outer perimeter boundary rim 642O may have a constant or changing width over the course of its perimeter. Alternatively, if desired, the outer perimeter boundary rim 642O may be interrupted by and/or terminate at the area of the forefoot edge support, as will be described in more detail below.

<FIG> and <FIG> further show that the outer perimeter boundary rim 642O of the ground-engaging component <NUM> defines an open space <NUM> at least at a forefoot support area of the ground-engaging component <NUM>, and in this illustrated example, the open space <NUM> extends into the arch support area and the heel support area of the ground-engaging component <NUM>. The rearmost extent 642R of the outer perimeter boundary rim 642O of this example is located within the heel support area, and optionally at a rear heel support area of the ground-engaging component <NUM>.

The outer perimeter boundary rim 642O of this illustrated example ground-engaging component <NUM> defines an upper-facing surface 648U and a ground-facing surface <NUM> opposite the upper-facing surface 648U. The upper-facing surface 648U provides a surface for supporting the wearer's foot and/or engaging the upper (and/or optionally engaging any present midsole component). The outer perimeter boundary rim 642O may provide a relatively large surface area for securely supporting at least a portion of (and optionally all of) a plantar surface of a wearer's foot. Further, the outer perimeter boundary rim 642O may provide a relatively large surface area for securely engaging another footwear component (such as the bottom surface of the upper), e.g., a surface for bonding via adhesives or cements, for supporting stitches or sewn seams, for supporting mechanical fasteners, etc..

<FIG> further illustrate that the ground-engaging component <NUM> of this example sole structure <NUM> includes a support structure <NUM> that extends from the outer perimeter boundary rim 642O into and at least partially across (and optionally completely across) the open space <NUM>. The top surface of this example support structure <NUM> at locations within the open space <NUM> lies flush with and/or smoothly transitions into the outer perimeter boundary rim 642O to provide a portion of the upper-facing surface 648U (and may be used for the purposes of the upper-facing surface 648U as described above). This support structure <NUM> extends from the ground-facing surface <NUM> of the outer perimeter boundary rim 642O to define at least a portion of the ground-facing surface <NUM> of the ground-engaging component <NUM>. This sole structure <NUM>, including the support structure <NUM>, may have any of the characteristics, options, features, etc., of the sole structure <NUM> described above in conjunction with <FIG> (including any features of the matrix structure <NUM>). Accordingly, more detailed explanations of the potentially common features of sole structure <NUM> and/or support structure <NUM> are omitted.

One difference between the sole structure <NUM> of <FIG> and the sole structures <NUM> described above relates to the inclusion of a forefoot edge support <NUM> extending along and defining at least a portion of a forefoot edge of the ground-engaging component 64O. As shown in <FIG>, <FIG>, <FIG>, a bottom surface <NUM> of the forefoot edge support <NUM> slants in an outward and downward direction from a location adjacent or within the open space <NUM> toward the outer forefoot edge of the ground-engaging component <NUM>. The bottom surface <NUM> may be relatively flat or smoothly curved and may contact the ground in use. The slanted bottom surface <NUM> builds up the forefoot perimeter edge of the ground-engaging component <NUM> to provide additional support, e.g., when running curves on a track (and particularly if the curves are banked). For track events that run around an oval track in a counter-clockwise direction, the forefoot edge support <NUM> may be provided on the lateral side of the right shoe and/or on the medial side of the left shoe (as will be described in more detail below in conjunction with <FIG> and <FIG>). As further shown in the figures, in this illustrated example, the forefoot edge support <NUM> terminates at one end 660T at a forward toe location (e.g., at P = <NUM> to <NUM>, and in some examples, at P = <NUM> to <NUM>, or even at P = <NUM> to <NUM>) and at its other end 660A at or near an arch support area (e.g., at P = <NUM> to <NUM>, and in some examples, at P = <NUM> to <NUM>).

Further, as shown in <FIG> and <FIG>, the bottom surface <NUM> of the forefoot edge support <NUM> may have a maximum width dimension "Ws" of less than <NUM> inches (<NUM>) wide, and in some examples, less than <NUM> inches (<NUM>) wide, less than <NUM> inches (<NUM>) wide, or even less than <NUM> inches (<NUM>) wide, measuring in the transverse direction, measuring outward from the open space, and/or measuring from the outside edge of the support structure <NUM>. At its maximum width dimension Ws location in the transverse direction, the forefoot edge support surface <NUM> may extend in the transverse direction for a distance less than a distance that the open space <NUM> and/or the support structure <NUM> extends at that same transverse direction location, e.g., the forefoot edge support <NUM> may extend less than ½ of the sole structure <NUM> width and/or less than ½ of the open area <NUM> width at the forefoot edge support <NUM>'s widest transverse dimension location). Additionally or alternatively, if desired, the forefoot edge support surface <NUM> may extend inward (into the open space <NUM>) beyond the interior edge 642I of the outer perimeter boundary rim 642O and/or outward beyond the exterior edge 642E of the outer perimeter boundary rim 642O. At this widest maximum width dimension Ws location, the bottom surface <NUM> of the forefoot edge support <NUM> may be at least <NUM> inches (<NUM>) wide, and in some examples, at least <NUM> inch (<NUM>) wide.

As shown in <FIG>, <FIG>, the exterior edge 642E of the outer perimeter boundary rim 642O may be located directly below a footwear upper's outer edge and/or at a location directly below (and provided to directly support) an outer forefoot edge of a wearer's foot (e.g., when the sole structure <NUM> is on a horizontal support surface). The forefoot edge support <NUM> may extend at least <NUM> inches (<NUM>), at least <NUM> inches (<NUM>), or even at least <NUM> inch (<NUM>) outward from the outer edge of the upper and/or the exterior edge 642E of the outer perimeter boundary rim 642O (dimension WF) at its maximum width location.

As noted above, the bottom surface <NUM> of the forefoot edge support <NUM> in this example slants in an outward and downward direction, e.g., from a location adjacent or within the open space <NUM> toward and to a location at or adjacent the outer forefoot edge of the ground-engaging component <NUM>. Indeed, the forefoot edge support <NUM> may form the outer forefoot edge of the ground-engaging component <NUM> in at least some of the forefoot area. As shown in <FIG>, the slant angle α of at least some portions of the surface <NUM> (e.g., with respect to a horizontal plane or a base surface of the ground-engaging component <NUM>) may be within a range of <NUM>° to <NUM>° downward, and in some examples, within the range of <NUM>° to <NUM>° downward or even <NUM>° to <NUM>° downward (e.g., at about <NUM>°).

As further shown in <FIG>, <FIG>, the bottom surface <NUM> of the forefoot edge support <NUM> slants downward and outward over at least some (and optionally a majority or substantially all) of its width (e.g., from its base area <NUM> or origin at the open area defined by the outer perimeter boundary rim 642O to a location at or immediately adjacent its outermost edge 660E) at the angle α described above. The outermost edge 660E may include a rounded corner moving from bottom surface <NUM> to its exposed top surface, e.g., as shown in <FIG>. As also shown in <FIG>, <FIG>, the exposed top surface of the forefoot edge support <NUM> also slants downwardly and outwardly from the exterior edge 642E of the outer perimeter boundary rim 642O to the free, exposed edge 660E.

<FIG> further show that the forefoot edge support <NUM> of this example includes a plurality of edge support components <NUM> that extend to and define a free outer edge 660E of the forefoot edge support <NUM>. While other arrangements and/or numbers of parts are possible, in this illustrated example, the plurality of edge support components <NUM> are interconnected at their interior side and/or upper side by base surface <NUM> and are separated from one another at their exterior side and/or bottom side by gaps <NUM>. At their outermost locations, the gaps <NUM> between adjacent edge support components <NUM> may have any desired size. As some more specific examples, at their outermost locations (at edge 660E) and with the sole structure <NUM> in an unloaded condition, the gaps <NUM> may have any one or more of the following properties: at least <NUM> (<NUM> inch) wide, at least <NUM> (<NUM> inch) wide, less than <NUM> (<NUM> inch) wide, less than <NUM> (<NUM> inch) wide, less than <NUM> (<NUM> inch) wide, or even less than <NUM> (<NUM> inch) wide. Providing the gaps <NUM> and separating at least portions of the forefoot edge support <NUM> into components <NUM> helps improve the flexibility and reduce the weight of the sole structure <NUM> and improves the natural motion capabilities of the sole structure <NUM>. Alternatively, if desired, one or more of the edge support components <NUM> may be separate structures from one or more other of the edge support components <NUM> (e.g., the interconnecting base surface <NUM> can be omitted over at least some of the length of forefoot edge support <NUM> and/or at least some (and optionally all) of the edge support components <NUM> may extend from the outer perimeter boundary rim 642O and/or the support structure <NUM>).

The forefoot edge support <NUM> may extend downward from the ground-facing surface <NUM> of the outer perimeter boundary rim 642O. As some additional or alternative potential features, e.g., as shown in <FIG>, the outer perimeter boundary rim 642O may define an exterior perimeter edge 642E and an interior perimeter edge 642I, and the forefoot edge support <NUM> may extend from the open space <NUM> and/or support structure <NUM> from a location inside the interior perimeter edge <NUM> and/or to a location beyond the exterior perimeter edge 642E. Alternatively, if desired, the forefoot edge support <NUM> may replace a portion of the outer perimeter boundary rim 642O and/or smoothly morph to form the outer perimeter boundary rim 642O at the forefoot area. Also, as shown in <FIG> and <FIG>, the support structure <NUM> may extend to and/or morph into the forefoot edge support <NUM> (e.g., morph into surface <NUM> and/or <NUM>).

In the example sole structure <NUM> shown in <FIG>, the sole structure <NUM> is a sole structure for inclusion in a right shoe (with the forefoot edge support <NUM> located at the forefoot lateral side of the sole structure <NUM>). This sole structure <NUM> may be well adapted for use in a right track shoe, and particularly for running events run in a counter-clockwise direction around an oval track (optionally a banked track). The forefoot edge support <NUM> provides an angled base surface <NUM> that engages the curves and/or banks and helps the wearer (who will typically lean left while running the curves) better push off the track surface (e.g., making the push off in more of a normal direction with respect to the track surface). If desired, the inside/left shoe (e.g., to be paired with an outside/right shoe including sole structure <NUM>) need not have a lateral side forefoot edge support like support <NUM>. As some more specific examples, if desired, the inside/left shoe may have sole structures like those described above in conjunction with <FIG> (e.g., sole structures <NUM>).

As another option, if desired, sole structure <NUM> may be paired with a left shoe that also has a forefoot edge support. <FIG> and <FIG> illustrate a top view and a bottom view, respectively, of one example of a pair <NUM> of sole structures 702R and <NUM> for such a pair of shoes. If desired, in this sole structure pair <NUM>, the right sole structure 702R may have any of the structures, features, and/or options described above with respect to sole structures <NUM> and/or <NUM> and <FIG>. In the illustrated example, however, the forefoot edge support <NUM> of sole structure 702R has somewhat fewer edge support components <NUM> and the edge support components <NUM> are generally separated from one another by somewhat larger gaps <NUM> as compared to the sole structure <NUM> shown in <FIG>. While any desired numbers of edge support components <NUM> may be provided (e.g., from <NUM> to <NUM>), in the example of <FIG>, <NUM> edge support components <NUM> are shown, while in the example of <FIG> and <FIG>, <FIG> edge support components <NUM> are shown.

<FIG> and <FIG> further show that the left sole structure <NUM> in this example includes a forefoot edge support <NUM> located at the medial forefoot side of the sole structure <NUM>. The left sole structure <NUM> forefoot edge support <NUM> may have any of the structural features, sizes, orientations, arrangements, and/or options discussed above with respect to the edge support <NUM> of <FIG>, but the forefoot edge support <NUM> is provided on the medial forefoot side of the sole structure <NUM> rather than on the lateral side. This sole structure <NUM>, particularly when combined with one of the sole structures <NUM>, 702R shown in <FIG>, may be well adapted for use in a left track shoe, and particularly for running events in a counter-clockwise direction around an oval and/or banked track (e.g., such as the <NUM>, <NUM>, <NUM>, etc.). The forefoot edge support <NUM> provides an angled bottom surface (e.g., like surface <NUM>) that engages the track surface (e.g., banks) on the track's curves and helps the wearer better steer and push off the track surface. If desired, the right shoe (e.g., to be paired with a left shoe including sole structure <NUM>) need not have a forefoot edge support of the types described above.

Accordingly, the example sole structures <NUM> and 702R shown in <FIG> and <FIG> have an "asymmetric" construction in that the right and left sole structures are not mirror images of one another. Differences in the locations and/or other properties of the forefoot edge supports <NUM>, <NUM>, however, are not necessarily the only areas of difference in mirror image symmetry between the left sole structure <NUM> and right sole structure 702R in this example. For example, in this illustrated example sole structure pair <NUM>, the cleat mount areas <NUM> on the left sole structure <NUM> do not constitute mirror images of the cleat mount areas <NUM> on the right sole structure 702R. The cleat mount areas <NUM> may be structures for engaging a detachable cleat or they may be locations accommodating permanently mounted primary cleat elements, e.g., of the types described above.

More specifically, as shown in <FIG> and <FIG>, in the sole structure 702R, four primary cleat mount areas <NUM> are provided, with three along the medial side edge in the forefoot and/or arch area and one on the lateral side edge in the forefoot and/or arch area. The rearmost cleat mount area <NUM> on the medial side and the cleat mount area <NUM> on the lateral side of sole structure 702R may be at substantially the same location along the longitudinal direction of the sole structure 702R (e.g., generally beneath the first and fifth metatarsal head support areas). The two forward medial side cleat support mount areas <NUM> of this example are located beneath the first metatarsal and/or toe support areas. If desired, the cleat mount areas <NUM> may be at the locations described above with respect to <FIG> (and/or those described in more detail below with respect to <FIG>). At these locations, the cleat support mount areas <NUM> (and any primary cleats engaged therewith) on the right sole structure 702R (e.g., for the "drive foot" on a curved track) provide support and traction to prevent sideways sliding and/or a strong "push off" during the toe off phase of a step cycle when running a counter-clockwise curve.

The illustrated example left sole structure <NUM>, on the other hand, includes three primary cleat mount areas <NUM>, with two along the medial side edge in the forefoot and/or arch area and one on the lateral side edge in the forefoot and/or toe area. The rearmost cleat mount area <NUM> on the medial side is located beneath the first metatarsal head support area. The two forward cleat mount areas <NUM> of this example sole structure <NUM> are located at the forward toe area. At these locations, the cleat mount areas <NUM> (and any primary cleats engaged therewith) on the left sole structure <NUM> (e.g., for the "steering foot" on a curved track) provide support and traction to enable better control or steering during the step cycle, particularly when running a counter-clockwise curve. The cleat mount areas <NUM> of this sole structure <NUM> may be at any of the locations described above with respect to <FIG> (and/or those described in more detail below with respect to <FIG>). In the specific example of <FIG>, the rearward medial primary traction element is located at about <NUM> and the two forward primary traction elements are located at about <NUM>. The rearward primary traction element may be the only primary traction element located between P=<NUM> and P=<NUM>.

The cleat mount areas <NUM> provided in the examples of <FIG> may have any of the structural features, sizes, orientations, arrangements, and/or options discussed above with respect to <FIG>, including the location features, the hexagonal type construction features, and/or the secondary traction element features.

<FIG> and <FIG> illustrate directional traction element features that may be included in ground-engaging components and/or articles of footwear in accordance with some aspects of this invention, including in any of the examples of this invention described above (e.g., in conjunction with any of the structures described above relating to <FIG>). <FIG> illustrates a forefoot area of a ground-engaging component <NUM> for an inside foot with respect to running around a curved track (e.g., for a left foot and for use on a conventional track running counter-clockwise), and <FIG> illustrates a forefoot area of a ground-engaging component 802R for an outside foot with respect to running around a curved track (e.g., for a right foot and for use on a conventional track running counter-clockwise).

When running around a curve on a track, the inside (e.g., left) leg/foot typically is the steering leg/foot, and the outside (e.g., right) leg/foot typically is the drive leg/foot. When running the curve, the inside/left foot plants early in the step cycle, and stance and rotation occur off the spike(s) of the ground-engaging component located beneath the ball area at the medial side of the foot. To better support this rotation (e.g., about arrow <NUM> of <FIG>), this example ground-engaging component <NUM> includes one primary traction element <NUM> (e.g., track spike) located on its medial side and no primary traction element(s) located in that same general longitudinal area of the ground-engaging component <NUM>, e.g., at the lateral side, between the medial and lateral sides, etc. The absence of primary traction elements at the central and lateral side of the ground-engaging component <NUM> at this longitudinal area better allow and facilitate this rotation. If desired, the primary traction element <NUM> may be located along the longitudinal direction of the ground-engaging component <NUM> (and/or a sole structure or article of footwear containing ground-engaging component <NUM>) between planes perpendicular to the longitudinal direction and located at <NUM> and <NUM> (and in some examples, between perpendicular planes located at <NUM> and <NUM>). This primary traction element <NUM>, located adjacent the medial side edge of the ground-engaging component <NUM>, may be the only primary traction element located between perpendicular planes located at <NUM> and <NUM> (and in some examples, the only primary traction element between perpendicular planes located at <NUM> and <NUM>).

As further shown by the arrows 806A-806D in <FIG>, the cells <NUM>/<NUM> in the matrix structure <NUM> are arranged generally in arcs around the primary traction element <NUM> to facilitate foot rotation about the primary traction element <NUM>. More specifically, as shown in <FIG>, a lateral side edge of the matrix structure <NUM> includes a plurality of cells <NUM>/<NUM> (e.g., at least three cells <NUM>/<NUM>, and optionally, at least three adjacent cells <NUM>/<NUM>) having their geographic centers lying substantially along curved arrow 806A, which may correspond to an arc of a circle (or other desired curve). If desired, this set of cells <NUM>/<NUM> along curved arrow 806A may be an outermost set of cells <NUM>/<NUM> along the lateral forefoot edge of the ground-engaging component <NUM>. Inside arrow 806A, another set of cells <NUM>/<NUM> having their geographic centers lying substantially along curved arrow 806B is provided (and the cells <NUM>/<NUM> along arrow 806A lie immediately adjacent the cells <NUM>/<NUM> along arrow 806B, in this illustrated example). Similarly, inside arrow 806B, another set of cells <NUM>/<NUM> having their geographic centers lying substantially along curved arrow 806C is provided (and the cells <NUM>/<NUM> along arrow 806B lie immediately adjacent the cells <NUM>/<NUM> along arrow 806C, in this illustrated example), and inside arrow 806C, another set of cells <NUM>/<NUM> having their geographic centers lying substantially along curved arrow 806D is provided (and the cells <NUM>/<NUM> along arrow 806C lie immediately adjacent the cells <NUM>/<NUM> along arrow 806D, in this illustrated example). More or fewer arcs 806A-806D (or other curves) of cells <NUM>/<NUM> may be arranged in this manner, if desired, without departing from this invention. While not a requirement, if desired, the arcs (or other curves) defined by two or more of arrows 806A-806D (or any additional corresponding groups of cells <NUM>/<NUM>) may have the same radius of curvature and/or may be concentric. A cell <NUM>/<NUM> is considered to lie "substantially along" an arc or other curve (e.g., a parabolic curve, an elliptical curve, an oval curve, or other standard curve, etc.) if its geographic center is located within <NUM> of the arc or other curve. Any desired number of arcs or other curves of cells <NUM>/<NUM> may be provided around primary traction element <NUM> without departing from this invention (e.g., from <NUM>-<NUM> arcs or other curves, and in some examples, from <NUM>-<NUM> arcs or other curves). As shown in <FIG>, the primary traction element <NUM> may be arranged inside (or on a concave side) of the arcs (or other curves) 806A-806D along which the cells <NUM>/<NUM> are substantially aligned.

In this forefoot area, secondary traction elements may be provided, e.g., at the corners of the generally hexagonal (or other polygonal shaped) matrix structure <NUM> that define the cells <NUM>/<NUM> at the ground-facing surface of the matrix <NUM>, e.g., in the manners described above in conjunction with <FIG>. The arc (or other curved) arrangement of cells <NUM>/<NUM> (e.g., along arrows 806A-806D as described above) may, in turn, provide clusters or groups of secondary traction elements arranged along arcs or other curves that generally curve in the same manner as arrows 806A-806D, as shown by arrows 808A-808D in <FIG>. More or fewer arcs (or other curves) 808A-808D of grouped secondary traction elements may be arranged in this manner, if desired, without departing from this invention. If desired, the arcs or other curves defined by two or more arrows 808A-808D (or any additional groups of secondary traction elements) may have the same radius of curvature and/or may be concentric. A secondary traction element is considered to lie "substantially along" an arc or other curve if its peak (or ground-engaging point or surface) is located within <NUM> of the arc or other curve. As shown in <FIG>, the primary traction element <NUM> may be arranged inside (or on a concave side) of the arcs (or other curves) 808A-808D along which the secondary traction elements are substantially aligned.

The example ground-engaging component <NUM> of <FIG> further includes two forward toe based primary traction elements <NUM> and <NUM> and a third forefoot primary traction element 804F located along the lateral side edge of the ground-engaging component <NUM> just rearward of primary traction element <NUM>. These primary traction elements 804F, <NUM>, and <NUM> provide traction for the toe-off phase of the step cycle. These primary traction elements 804F, <NUM>, and <NUM> may be located sufficiently forward from primary traction element <NUM> so as not to interfere (or not to substantially interfere) with rotation about primary traction element <NUM> as described above. As some more specific examples, the primary traction elements 804F, <NUM>, and <NUM> (and optionally all forefoot based primary traction elements other than element <NUM>) may be located forward of a plane perpendicular to the longitudinal direction of the ground-engaging component <NUM> (or the longitudinal direction of a sole structure or an article of footwear) located at <NUM> and optionally, forward of a perpendicular plane located at <NUM>.

<FIG> illustrates example features of the outside (e.g., right) ground-engaging component 802R (e.g., for the drive leg/foot) when running around a curve on a track. In contrast to the inside foot, as described above, when running the curve, the outside/right foot rotates later in the step cycle, and stance and rotation occur off more forward spike(s) of the ground-engaging component (e.g., forward-most primary traction element 814T in <FIG>). To better support this rotation, this example ground-engaging component 802R includes one primary traction element 814T (e.g., track spike) located on its medial side at the forward toe area and no primary traction element(s) located in that same general longitudinal area of the ground-engaging component 802R, e.g., at the lateral side of the forward toe area, etc. The absence of primary traction elements at the lateral side of the forward toe area of this example ground-engaging component 802R at this longitudinal area better allow and facilitate this rotation. If desired, the primary traction element 814T may be located along the longitudinal direction of the ground-engaging component 802R (and/or a sole structure or article of footwear containing ground-engaging component 802R) forward of a plane perpendicular to the longitudinal direction and located at <NUM> (and in some examples, forward of a perpendicular plane located at <NUM>). This primary traction element 814T, located adjacent the medial side edge of ground-engaging component 804R, may be the only primary traction element located forward of a perpendicular plane located at <NUM> (and in some examples, the only primary traction element forward of a perpendicular plane located at <NUM>).

The example of <FIG> further shows other primary traction elements located rearward of primary traction element 814T, namely, a lateral side primary traction element <NUM>, a rearward medial side primary traction element 814R and a forward medial side primary traction element 814F. These primary traction elements <NUM>, 814R, and 814F may be located sufficiently rearward so as not to interfere (or not to substantially interfere) with rotation about primary traction element 814T as described above (and as will be described in more detail below). As some more specific examples, some or all of the primary traction elements <NUM>, 814R, and 814F may be located rearward of a plane perpendicular to the longitudinal direction of the ground-engaging component 802R (or the longitudinal direction of a sole structure or an article of footwear containing it) and located at <NUM> (and optionally, rearward of a perpendicular plane located at <NUM>). Additionally or alternatively, if desired, the primary traction elements <NUM>, 814R, and 814F may be located between perpendicular planes located at <NUM> and <NUM> (and, if desired, the rearmost primary traction elements <NUM>, and 814R may be located between perpendicular planes located at <NUM> and <NUM>). The three medial side primary traction elements 814T, 814F, and 814R provide substantial traction for the toe off phase of the step cycle.

As further shown by the arrows 818A-818C in <FIG>, the cells <NUM>/<NUM> in the matrix structure <NUM> of this ground-engaging component 802R are arranged generally in arcs (or other curves, such as parabolic curves, elliptical curves, oval curves, other standard curves, etc.) around the primary traction element 814T to facilitate the desired foot rotation about the primary traction element 814T. More specifically, as shown in <FIG>, a lateral side of the matrix structure <NUM> includes a plurality of cells <NUM>/<NUM> (e.g., at least three cells <NUM>/<NUM>, and optionally, at least three adjacent cells <NUM>/<NUM>) arranged such that a substantial number of secondary traction elements are oriented on arcs or other curves, e.g., 818A, 818B, 818C. As described above, secondary traction element features may be formed at the corners of the generally hexagonal (or other polygonal shaped) matrix structure <NUM> that define the cells <NUM>/<NUM> at the ground-facing surface of the matrix <NUM>, e.g., in the manners described above in conjunction with <FIG>. The arc or other curved arrangement of some of these secondary traction elements (e.g., along arcs 818A-818C as described above) provides generally grouped secondary traction elements. More or fewer arcs or other curves 818A-818C of grouped secondary traction elements may be arranged in this manner, if desired, without departing from this invention. If desired, each of arcs or other curves 818A-818C (and any other present groups) may include at least <NUM> secondary traction elements that lie "substantially along" it (and in some examples, the arcs or other curves each may include at least <NUM>, at least <NUM>, at least <NUM>, or even at least <NUM> secondary traction elements that lie "substantially along" it). These generally arc or curve arranged clusters or groups of secondary traction elements (e.g., along arcs 818A-818C) facilitate the late stage rotation of the foot about primary traction element 814T, as described above. If desired, the arcs or curves defined by two or more of arrows 818A-818C (or any additional arcs or curves) may have the same radius of curvature and/or may be concentric. As shown in <FIG>, the primary traction element 814T may be arranged inside (or on a concave side) of the arcs (or other curves) 818A-818C along which the secondary traction elements are substantially aligned.

Claim 1:
A ground-engaging component (<NUM>) for an article of footwear, comprising:
an outer perimeter boundary rim (242O) that at least partially defines an outer perimeter of the ground-engaging component (<NUM>),
wherein the outer perimeter boundary rim (242O) defines an upper-facing surface (248U) and a ground-facing surface (<NUM>) opposite the upper-facing surface (248U), and
wherein the outer perimeter boundary rim (242O) defines an exterior perimeter edge and an interior perimeter edge, and wherein the outer perimeter boundary rim (242O) defines an open space (<NUM>) at least at a forefoot support area of the ground-engaging component (<NUM>); and
a forefoot edge support (<NUM>) extending along and defining at least a portion of a first forefoot edge of the ground-engaging component (<NUM>),
wherein a bottom surface (<NUM>) of the forefoot edge support (<NUM>) slants in an outward and downward direction from a location adjacent the open space toward the first forefoot edge,
wherein the forefoot edge support (<NUM>) extends outward beyond the exterior perimeter edge of the outer perimeter boundary rim,
wherein the forefoot edge support (<NUM>) includes a plurality of edge support components (<NUM>) defining a free outer edge (660E) of the forefoot edge support (<NUM>),
wherein the forefoot edge support (<NUM>) includes a base area, wherein at least some of the plurality of edge support components (<NUM>) extend to the free outer edge from the base area,
wherein at the free outer edge, at least some of the plurality of edge support components (<NUM>) are separated from at least one respective adjacent edge support component by a gap,
wherein: (a) the forefoot edge support (<NUM>) is provided only on a lateral forefoot side edge of the ground-engaging component (<NUM>), or (b) the forefoot edge support is provided only on a medial forefoot side edge of the ground-engaging component (<NUM>), and
the ground-engaging component (<NUM>) further comprising: a matrix structure (<NUM>) extending from the ground-facing surface (<NUM>) and at least partially across the open space (<NUM>) at least at the forefoot support area to define an open cellular construction with plural open cells (<NUM>, <NUM>) across the open space (<NUM>) at least at the forefoot support area.