Ground-engaging structures for articles of footwear

Abstract

Ground-engaging components for articles of footwear 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 open space at least at a forefoot support area of the ground-engaging component, wherein the outer perimeter boundary rim is shaped such that the outer perimeter of the ground-engaging component tapers or curves inward moving from a forefoot support area to an arch support area, and wherein a narrowest dimension from a lateral side edge to a medial side edge of the outer perimeter boundary rim is located in a heel support area of the ground-engaging component; and (b) a support structure extending into or at least partially across the open space. The ground-engaging component may have a narrower width dimension in a central heel or rear heel support area than in the arch support area.

Claims

1. A ground-engaging component for an article of footwear, comprising: an outer perimeter boundary rim that 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, wherein the outer perimeter boundary rim extends continuously and completely around the outer perimeter of the ground-engaging component, and wherein the outer perimeter boundary rim defines an open space that extends: (i) from the upper-facing surface to the ground-facing surface and (ii) from a forefoot support area, through an arch support area, and into a heel support area of the ground-engaging component; and a support structure formed as a matrix of cells that extend beneath the ground-facing surface of the outer perimeter boundary rim and completely across the open space to define an open cellular construction, wherein the matrix of cells extends from the forefoot support area, through the arch support area, and into the heel support area of the ground-engaging component and provides plural open cells within the open space, wherein the plural open cells include a first plurality of open cells defined by generally smooth sloped sidewalls extending toward one another from the upper-facing surface to the ground-facing surface, and wherein for each of the first plurality of open cells, a cell entrance size from the upper-facing surface is smaller than a cell entrance size from the ground-facing surface.

2. The ground-engaging component according to claim 1, wherein the matrix of cells includes one or more closed cells that are closed off by the ground-facing surface of the outer perimeter boundary rim.

3. The ground-engaging component according to claim 1, wherein a first width dimension from an outermost lateral side edge to an outermost medial side edge of the outer perimeter boundary rim in a central heel support area of the ground-engaging component is less than a second width dimension from the outermost lateral side edge to the outermost medial side edge in the arch support area.

4. The ground-engaging component according to claim 1, wherein the support structure further defines at least one cleat support area at or at least partially in a portion of the ground-facing surface of the outer perimeter boundary rim.

5. The ground-engaging component according to claim 4, wherein the at least one cleat support area includes: a first cleat support area at or at least partially in a lateral side of the ground-facing surface of the outer perimeter boundary rim; a second cleat support area at or at least partially in the lateral side of the ground-facing surface of the outer perimeter boundary rim and located forward of the first cleat support area; a third cleat support area at or at least partially in a medial side of the ground-facing surface of the outer perimeter boundary rim; and a fourth cleat support area at or at least partially in the medial side of the ground-facing surface of the outer perimeter boundary rim and located forward of the third cleat support area.

6. The ground-engaging component according to claim 1, wherein an average open cell size defined by the plural open cells on a medial forefoot side support area of the ground-engaging component is smaller than an average open cell size defined by the plural open cells on a lateral forefoot side support area of the ground-engaging component.

7. The ground-engaging component according to claim 1, wherein an average open cell size defined by the plural open cells in a first metatarsal head support area of the ground-engaging component is smaller than an average open cell size defined by the plural open cells in a fourth and fifth metatarsal head support area of the ground-engaging component.

8. The ground-engaging component according to claim 1, wherein an average open cell size defined by the plural open cells on a medial side of a longitudinal center line of the ground-engaging component is smaller than an average open cell size defined by the plural open cells on a lateral side of the longitudinal center line.

9. The ground-engaging component according to claim 1, wherein the support structure defines a first cluster of at least ten secondary traction elements within a 30 mm diameter circle at a first location along a medial side of the ground-engaging component rearward of a first metatarsal head support area of the ground-engaging component and forward of the heel support area of the ground-engaging component; and a second cluster of at least ten secondary traction elements within a 30 mm diameter circle at a second location along the medial side of the ground-engaging component rearward of the first cluster and forward of the heel support area of the ground-engaging component.

10. The ground-engaging component according to claim 1, wherein the plural open cells include a first open cell and an adjacent second open cell, wherein the first open cell has an opening with a cross sectional area of less than 50% of a cross sectional area of an opening of the second open cell, and wherein a geographic center of the first open cell is located closer to an outermost medial side edge than is a geographic center of the second open cell.

11. The ground-engaging component according to claim 10, wherein the second open cell is elongated in a medial side-to-lateral side direction and wherein the first open cell is elongated in a front-to-rear direction.

12. The ground-engaging component according to claim 1, wherein at the ground-facing surface, the support structure further defines a plurality of hexagonal ridges extending around cell entrances of the first plurality of open cells, and wherein the plurality of hexagonal ridges and the generally smooth sloped sidewalls form generally triangular-shaped cross sections extending from the upper-facing surface to the ground-facing surface in at least some locations around the first plurality of open cells.

13. The ground-engaging component according to claim 1, wherein the support structure further defines a plurality of secondary traction elements, and wherein the plurality of secondary traction elements includes at least one set of six substantially pyramid-type structures arranged around a single open cell.

14. An article of footwear, comprising: an upper; and a sole structure engaged with the upper, wherein the sole structure includes a ground-engaging component having: an outer perimeter boundary rim that 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, wherein the outer perimeter boundary rim extends continuously and completely around the outer perimeter of the ground-engaging component, and wherein the outer perimeter boundary rim defines an open space that extends: (i) from the upper-facing surface to the ground-facing surface and (ii) from a forefoot support area, through an arch support area, and into a heel support area of the ground-engaging component; and a support structure formed as a matrix of cells that extend beneath the ground-facing surface of the outer perimeter boundary rim and completely across the open space to define an open cellular construction, wherein the matrix of cells extends from the forefoot support area, through the arch support area, and into the heel support area of the ground-engaging component and provides plural open cells within the open space, and wherein the support structure further defines a plurality of secondary traction elements that includes at least one set of substantially pyramid-type structures arranged around a single open cell.

15. The article of footwear according to claim 14, wherein the matrix of cells includes one or more closed cells that are closed off by the ground-facing surface of the outer perimeter boundary rim.

16. The article of footwear according to claim 14, wherein a first width dimension from an outermost lateral side edge to an outermost medial side edge of the outer perimeter boundary rim in a central heel support area of the ground-engaging component is less than a second width dimension from the outermost lateral side edge to the outermost medial side edge in the arch support area.

17. The article of footwear according to claim 14, wherein the plural open cells include a first plurality of open cells defined by generally smooth sloped sidewalls extending toward one another from the upper-facing surface to the ground-facing surface, and wherein for each of the first plurality of open cells, a cell entrance size from the upper-facing surface is smaller than a cell entrance size from the ground-facing surface.

18. The article of footwear according to claim 17, wherein at the ground-facing surface, the support structure further defines a plurality of hexagonal ridges extending around cell entrances of the first plurality of open cells, and wherein the plurality of hexagonal ridges and the generally smooth sloped sidewalls form generally triangular-shaped cross sections extending from the upper-facing surface to the ground-facing surface in at least some locations around the first plurality of open cells.

19. The article of footwear according to claim 14, wherein the sole structure further includes a midsole component between the ground-engaging component and a bottom of the upper, and wherein a bottom surface of the midsole component is exposed through at least some of the plural open cells of the matrix of cells.

20. The article of footwear according to claim 14, wherein the sole structure further includes a midsole component between the ground-engaging component and a bottom of the upper, and wherein a bottom surface of the midsole component is exposed at an exterior of the sole structure and extends outside of an outermost lateral side edge and outside of an outermost medial side edge of the ground-engaging component at least at a heel support area of the sole structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing Summary, as well as 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.

(2) FIG. 1 is provided to help illustrate and explain background and definitional information useful for understanding certain terminology and aspects of this invention;

(3) FIGS. 2A-2D provide a lateral side view, a bottom view, an enlarged bottom view around a cleat mount area, and an enlarged perspective view around a cleat mount area, respectively, of an article of footwear in accordance with at least some aspects of this invention;

(4) FIGS. 3A and 3B provide a top view and a bottom view, respectively, of a ground-engaging component in accordance with at least some aspects of this invention;

(5) FIGS. 4A through 4D are various views of example sole structures and ground-engaging components in accordance with this invention that illustrate additional example features and aspects of the invention; and

(6) FIGS. 5A through 5H provide various views to illustrate additional features of the ground-engaging component's support structure in accordance with some example features of this invention.

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

DETAILED DESCRIPTION

(8) In the following description of various examples of footwear structures and components according to the present invention, 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.

(9) FIGS. 2A and 2B provide lateral side and bottom views, respectively, of an article of footwear 200 in accordance with at least some aspects of this invention. This example article of footwear 200 is a track shoe, and more specifically, a track shoe targeted for middle and/or relatively long distance runs, such as 800 m, 1500 m, 3K's, 5K's, 10K's, etc. Aspects of this invention, however, also may be used in shoes for other distance runs and/or other types of uses or athletic activities. The article of footwear 200 includes an upper 202 and a sole structure 204 engaged with the upper 202. The upper 202 and sole structure 204 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.).

(10) The upper 202 of this example includes a foot-receiving opening 206 that provides access to an interior chamber into which the wearer's foot is inserted. The upper 202 further includes a tongue member 208 located across the foot instep area and positioned so as to moderate the feel of the closure system 210 (which in this illustrated example constitutes a lace type closure system). In this illustrated example, the rear heel area of the upper 202 includes an opening 212 defined therethrough, and a rear heel area of the wearer's foot may be visible and/or exposed through this opening 212.

(11) As mentioned above, the upper 202 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 202 (and optionally a majority, all, or substantially all of the upper 202) may be formed as a woven textile component and/or a knitted textile component. The textile components for upper 202 may have structures and/or constructions like those provided in FLYKNIT® brand footwear and/or via FLYWEAVE™ technology available in products from NIKE, Inc. of Beaverton, Oreg.

(12) Additionally or alternatively, if desired, the upper 202 construction may include uppers having foot securing and engaging structures 214 (e.g., “dynamic” and/or “adaptive fit” structures), e.g., of the types described in U.S. Patent Appln. Publn. No. 2013/0104423, which publication is entirely incorporated herein by reference. More specifically, as shown in FIG. 2A, the lace 210 loops through one or more textile, fiber, filament, or wire type structures 214 (e.g., substantially unstretchable components) located on each side of the instep opening (only the lateral side is shown in FIG. 2A). The components 214 may themselves and/or may engage other components that partially or completely wrap around the wearer's foot (e.g., extending between at least some portion of the sole structure 204 and the upper 202, between layers of the upper 202, and/or beneath a plantar surface of a wearer's foot) so that when the lace 210 is tightened, the components 214 tighten and at least partially wrap around the wearer's foot and securely hold to it. As some additional examples, if desired, uppers and 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, Oreg. Additionally or alternatively, if desired, uppers and 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 U.S. Pat. Nos. 7,347,011 and/or 8,429,835 may be used without departing from this invention (each of U.S. Pat. Nos. 7,347,011 and 8,429,835 is entirely incorporated herein by reference).

(13) The sole structure 204 of this example article of footwear 200 now will be described in more detail. As shown in FIGS. 2A and 2B, the sole structure 204 of this example includes two main components: a midsole component 220 and a ground-engaging component 240 (optionally engaged with the bottom surface 220S (and optionally side surface) of the midsole component 220 via adhesives or cements, mechanical fasteners, sewing or stitching, etc.). The ground-engaging component 240 of this example has its rearmost extent 242R located at a rear heel support area, but rearmost extent 242R may be located somewhat forward of a rearmost extent 220R of the midsole component 220. The midsole component 220 may be located between (a) a bottom surface of the upper 202 (e.g., a strobel member or other bottom upper component) and (b) a top surface of the ground-engaging component 240. If desired, the midsole component 220 may form a portion of the ground-contacting surface of the sole 204. These sole structure 204 components will be described in more detail below.

(14) One main foot support component of this sole structure 204 is the midsole component 220, which in this illustrated example extends to support an entire plantar surface of the wearer's foot (e.g., from the forward-most toe location FT to the rearmost heel location RH and from the lateral side edge to the medial side edge along the entire longitudinal length of the sole structure 204). This midsole component 220, which may be made from one or more parts, may be constructed from a polymeric foam material, such as a polyurethane foam or an ethylvinylacetate (“EVA”) foam as are known and used in the footwear arts. Additionally or alternatively, if desired, at least some portion of the midsole component 220 may constitute a fluid-filled bladder, e.g., of the types conventionally known and used in the footwear arts (e.g., available in NIKE “AIR” Brand products), and/or one or more mechanical shock-absorbing components.

(15) In this illustrated example, a bottom surface 220S of the midsole component 220 is visible/exposed at an exterior of the sole structure 204 substantially throughout the bottom of the sole structure 204 (and at least over more than 40% and even more than 50% of the bottom surface area of the sole structure 204). As shown in FIG. 2B, the bottom surface 220S of the midsole component 220 is exposed at the forefoot support area, the arch support area, and/or the heel support area (through open cells 252 and/or partially open cells 254 of the ground-engaging component 240 (also called the “open space” herein) described in more detail below); in the arch support area outside of the ground-engaging component 240; and in the heel support area outside of the ground-engaging component 240.

(16) Example ground-engaging components 240 for sole structures 204/articles of footwear 200 in accordance with examples of this invention now will be described in more detail with reference to FIGS. 2A through 2D, as well as with reference to FIGS. 3A and 3B. As shown, these example ground-engaging components 240 include an outer perimeter boundary rim 242O, for example, that may be at least 3 mm (0.12 inches) wide (and in some examples, is at least 4 mm (0.16 inches) wide, at least 6 mm (0.24 inches) wide, or even at least 8 mm (0.32 inches) wide). This “width” Wo is defined as the direct, shortest distance from one edge (e.g., an exterior edge) of the outer perimeter boundary rim 242O to its opposite edge (e.g., interior edge) by the open space 244, as shown in FIG. 3A. While FIGS. 2B, 3A, and 3B show this outer perimeter boundary rim 242O extending completely and continuously around and defining 100% of an outer perimeter of the ground-engaging components 240, 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 240 such that the outer perimeter boundary rim 242O is present around only at least 75%, at least 80%, at least 90%, or even at least 95% of the outer perimeter of the ground-engaging component 240. The outer perimeter boundary rim 242O may have a constant or changing width Wo over the course of its outer perimeter. The outer perimeter boundary rim 242O also may extend to define the outer edge of at least a portion of the sole structure 204 (e.g., at least in the forefoot support area).

(17) FIGS. 2B-3B show that the outer perimeter boundary rim 242O of this example ground-engaging component 240 defines an open space 244 at least at a forefoot support area of the ground-engaging component 240, and in these illustrated examples, the open space 244 extends into the arch support area and the heel support area of the ground-engaging component 240. The rearmost extent 242R of the outer perimeter boundary rim 242O of these examples is located within the heel support area, and optionally at a rear heel support area of the ground-engaging component 240. The ground-engaging component 240 may fit and be fixed into a recess formed in the bottom surface 220S and/or side surface of the midsole component 220 (e.g., a recess molded into the midsole component 220 when it is formed), e.g., by cements or adhesives, mechanical fasteners, etc.

(18) The ground-engaging components 240 of these examples are shaped so as to extend completely across the forefoot support area of the sole structure 204 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 sole structure 204 at least at the forefoot medial and lateral sides and around the front toe area.

(19) As one moves rearward in the sole structure 204, however, the outer perimeter boundary rim 242O tapers inward (e.g., in a curved manner) with respect to the overall width of the sole structure 204, e.g., at least at an arch support area of the sole structure 204 (and optionally beginning at the forefoot support area). Therefore, as shown in FIG. 2B, the midsole component 220 forms an outer lateral edge 220L and/or an outer medial edge 220M of the sole structure 204 within at least some of the arch support area of the sole structure 204 and in the heel support area of the sole structure 204 (including around the rear heel area in this example). While the inwardly tapered (e.g., inwardly curved) and rearwardly extending end of the ground-engaging component 240 may have any desired shape, in this illustrated example, the rear end of the ground-engaging component 240 tapers inwardly and defines an elongated rear finger having a smoothly curved rear end area at which its rearmost extent 242R is located.

(20) As noted above, the outer perimeter boundary rim 242O of this example is shaped such that the outer perimeter of the ground-engaging component 240 tapers or curves inward moving from a forefoot support area to an arch support area. In this illustrated example, a narrowest width dimension W from a lateral side edge to a medial side edge of the outer perimeter boundary rim 242O across the open space 244 is located in a heel support area of the ground-engaging component 240 (the width dimension W is the direct, shortest distance from a point on the lateral outside edge to the medial outside edge of the outer perimeter boundary rim 242O, e.g., as shown in FIG. 2B). In other words, this example ground-engaging component 240 has a narrower width in the central and/or rear heel support area than in the arch support area. The ground-engaging component 240's narrowest width dimension W in the heel support area may be no more than 1.75 inches (44.5 mm) within the rearmost 1.5 inches (38.1 mm) of the ground-engaging component 240, and in some examples, no more than 1.75 inches (44.5 mm) within its rearmost 2 inches (50.8 mm), within its rearmost 2.5 inches (63.5 mm), or even within its rearmost 3 inches (76.2 mm). As still additional and/or alternative potential features, the ground-engaging component 240's width dimension W may be no more than 2 inches (50.8 mm), no more than 1.5 inches (38.1 mm), or even no more than 1.25 inches 31.8 mm) within any one or more of the rearmost dimension ranges of the ground-engaging component 240 described above.

(21) The outer perimeter boundary rim 242O of this illustrated example ground-engaging component 240 defines an upper-facing surface 248U (e.g., as shown in FIG. 3A) and a ground-facing surface 248G (e.g., as shown in FIGS. 2B and 3B) opposite the upper-facing surface 248U. The upper-facing surface 248U provides a surface (e.g., smooth and/or contoured surface) for supporting the wearer's foot and/or engaging the midsole component 220 (and/or optionally engaging the upper 202, if no exterior midsole is present at some or all locations of the sole structure 204). 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 220S of the midsole component 220 and/or a bottom surface of the upper 202), e.g., a surface for bonding via adhesives or cements, for supporting stitches or sewn seams, for supporting mechanical fasteners, etc.

(22) FIGS. 2B through 3B further illustrate that the ground-engaging component 240 of this example sole structure 204 includes a support structure 250 that extends from the outer perimeter boundary rim 242O into and at least partially across (and optionally completely across) the open space 244. The top surface of this example support structure 250 at locations within the open space 244 lies flush with and/or smoothly transitions 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).

(23) The support structure 250 of these examples extends from the ground-facing surface 248G of the outer perimeter boundary rim 242O to define at least a portion of the ground-facing surface 248G of the ground-engaging component 240. In the illustrated examples of FIGS. 2A-3B, the support structure 250 includes a matrix structure (also labeled 250 herein) extending from the ground-facing surface 248G of the outer perimeter boundary rim 242O and into, partially across, or fully across the open space 244 to define a cellular construction. The illustrated matrix structure 250 defines at least one of: (a) one or more open cells located within the open space 244, (b) one or more partially open cells located within the open space 244, and/or (c) one or more closed cells, e.g., beneath the outer perimeter boundary rim 242O. An “open cell” constitutes a cell in which the perimeter of the cell opening is defined completely by the matrix structure 250 (note, for example, cells 252 in FIGS. 2B and 3B). 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 250 within the open space 244 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 254 in FIGS. 2B and 3B). A “closed cell” may have the outer matrix structure 250 but no opening (e.g., it may be formed such that the portion of the matrix 250 that would define the cell opening is located under the outer perimeter boundary rim 242O). As shown in FIGS. 2B-3B, in the illustrated example matrix structures 250, at least 50% of the open cells 252 and/or partially open cells of the open cellular construction (and optionally, at least 60%, at least 70%, at least 80%, at least 90%, or even at least 95%) 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 244 and/or matrix structure 250 may extend to all areas of the ground-engaging component 240 within the outer perimeter boundary rim 242O.

(24) As further shown in FIGS. 2B, 2C, and 3B, the matrix structure 250 further defines one or more primary traction element or cleat support areas 260. Six separate cleat support areas 260 are shown in the examples of FIGS. 2A-3B, with: (a) three primary cleat support areas 260 on the lateral side of the ground-engaging component 240 (one at or near a lateral forefoot support area or a lateral midfoot support area of the ground-engaging component 240, one forward of that one in the lateral forefoot support area, and one forward of that one at the lateral toe support area) and (b) three primary cleat support areas 260 on the medial side of the ground-engaging component 240 (one at or near a medial forefoot support area or a medial midfoot support area of the ground-engaging component 240, one forward of that one in the medial forefoot support area, and one forward of that one at the medial toe support area). Primary traction elements, such as track spikes 262 or other cleats, may be engaged or integrally formed with the ground-engaging component 240 at the cleat support areas 260 (e.g., with one cleat or track spike 262 provided per cleat support area 260). The cleats or track spikes 262 (also called “primary traction elements” herein) may be permanently fixed in their associated cleat support areas 260, such as by in-molding the cleats or track spikes 262 into the cleat support areas 260 when the matrix structure 250 is formed (e.g., by molding). In such structures, the cleat or track spike 262 may include a disk or outer perimeter member that is embedded in the material of the cleat support area 260 during the molding process. As another alternative, the cleats or track spikes 262 may be removably mounted to the ground-engaging component 240, 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 mount area 260 or otherwise engaged in the mount area (e.g., by in-molding, adhesives, or mechanical connectors).

(25) The cleat support areas 260 can take on various structures without departing from this invention. In the illustrated example, the cleat support areas 260 are defined by and as part of the matrix structure 250 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 244. As various options, if desired, one or more of the cleat support areas 260 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 244, and/or (c) completely within the open space 244 (and optionally located at or adjacent the outer perimeter boundary rim 242O). When multiple cleat support areas 260 are present in a single ground-engaging component 240, all of the cleat support areas 260 need not have the same size, construction, and/or orientation with respect to the outer perimeter boundary rim 242O and/or open space 244 (although they all may have the same size, construction, and/or orientation, if desired).

(26) While other constructions are possible, in this illustrated example (e.g., see FIGS. 2B-2D), the cleat support areas 260 are formed as generally hexagonal shaped areas of thicker material into which or at which at least a portion of the cleat/spike 262 and/or mounting hardware will be fixed or otherwise engaged. The cleat support areas 260 are integrally formed as part of the matrix structure 250 in this illustrated example. The illustrated example further shows that the matrix structure 250 defines a plurality of secondary traction elements 264 dispersed around the cleat support areas 260. While other options and numbers of secondary traction elements 264 are possible, in this illustrated example, a secondary traction element 264 is provided at each of the six corners of the generally hexagonal structure making up the cleat support area 260 (such that each cleat support area 260 has six secondary traction elements 264 dispersed around it). The secondary traction elements 264 of this example are raised, sharp points or pyramid type structures made of the matrix 250 material and raised above a base surface 266 of the generally hexagonal cleat support area 260. The free ends of the primary traction elements 262 extend beyond the free ends of the secondary traction elements 264 (in the cleat extension direction and/or when the shoe 200 is positioned on a flat surface) and are designed to engage the ground first. Note FIG. 2D. If the primary traction elements 262 sink a sufficient depth into the contact surface (e.g., a track, the ground, etc.), the secondary traction elements 264 then may engage the contact surface and provide additional traction to the wearer. In an individual cleat mount area 260 around a single primary traction element 262, the points or peaks of the immediately surrounding secondary traction elements 264 that surround that primary traction element 262 may be located within 1.5 inches (3.8 cm) (and in some examples, within 1 inch (2.5 cm) or even within 0.75 inch (1.9 cm)) of the peak or point of the surrounded primary traction element 262 in that mount area 260.

(27) In at least some examples of this invention, the outer perimeter boundary rim 242O and the support structure 250 extending into/across the open space 244 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 240 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 structure 250. 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 structure 250 individually may be made of two or more parts.

(28) Optionally, the outer perimeter boundary rim 242O and the support structure 250, whether made from one part or more, will have a combined mass of less than 75 grams (exclusive of any separate primary traction elements, like spikes 262, and/or primary traction element mounting hardware), and in some examples, a combined mass of less than 65 grams, less than 55 grams, less than 45 grams, or even less than 40 grams. The entire ground-engaging component 240 also may have any of these same weighting characteristics. The ground-engaging component 240, in its final form, may be relatively flexible and pliable, e.g., so as to generally be capable of flexing and moving naturally with a wearer's foot during ambulatory activities and running/jogging events.

(29) FIGS. 4A through 5H are provided to illustrate additional features that may be present in ground-engaging components 240 and/or articles of footwear 200 in accordance with at least some aspects of this invention. FIG. 4A is a view similar to that of FIG. 2B with the rear heel RH and forward toe FT locations of the sole structure 204 identified and the longitudinal length L and direction identified. Planes perpendicular to the longitudinal direction (and going into and out of the page in the transverse direction) are shown, and the locations of various footwear 200 and/or ground-engaging component 240 features are described with respect to these planes. For example, FIG. 4A illustrates that the rear-most extent 242R of the ground-engaging component 240 is located at 0.025L of the sole structure 204. In some examples of this invention, however, this rear-most extent 242R of the ground-engaging component 240 may be located within a range of 0L and 0.12L, and in some examples, within a range of 0L to 0.1L or even 0L to 0.075L based on the sole structure 204's longitudinal length L.

(30) Potential primary traction element attachment locations for three primary traction elements 262 on each side of the ground-engaging component 240 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 262):

(31) TABLE-US-00001 More Specific Illustrated General Range Range Location Rear Lateral 0.44L to 0.75L 0.5L to 0.7L 0.54L Cleat Middle Lateral 0.6L to 0.85L 0.68L to 0.8L 0.74L Cleat Forward Lateral 0.8L to 0.96L 0.84L to 0.94L 0.9L Cleat Rear Medial 0.5L to 0.8L 0.56L to 0.72L 0.63L Cleat Middle Medial 0.64L to 0.92L 0.72L to 0.88L 0.8L Cleat Forward Medial 0.82L to 0.99L 0.86L to 0.97L 0.93L Cleat

(32) If desired, one or more additional primary traction elements 262 can be provided at other locations of the ground-engaging component 240 structure, including rearward of either or both of the identified rear cleats, between the identified lateral cleats and/or between the identified medial cleats, forward of either or both of the forward cleats, and/or between the lateral and medial cleats (e.g., in the matrix structure 250 within the open area 244, at a central forward toe location, etc.). In the illustrated example, each lateral cleat is located further rearward in the longitudinal direction L than its corresponding medial cleat (i.e., the rearmost lateral cleat is further rearward than the rearmost medial cleat, the middle lateral cleat is further rearward than the middle medial cleat, and/or the forwardmost lateral cleat is further rearward than the forwardmost medial cleat).

(33) FIG. 4A further illustrates that the forward-most extent of the outer perimeter boundary rim 242O of the ground-engaging component 240 is located at 1.0L (at the forward-most toe location FT). This forward-most extent of the outer perimeter boundary rim 242O, however, may be located at other places, if desired, such as within a range of 0.90L and 1.0L, and in some examples, within a range of 0.92L to 1.0L based on the sole structure 204's longitudinal length L.

(34) FIG. 4B further illustrates that in these example structures 240, some cells of the matrix structures 250 are generally formed in lines or along curves that extend across the ground-engaging component 240 and the sole structure 204. The term “cells” used in this context is used generically to refer to any one or more of open cells 252, partially open cells 254, and/or closed cells (e.g., cells completely formed by the matrix structure 250 and closed off within the outer perimeter boundary rim 242O) in any numbers or combinations. In some example structures 240 in accordance with this aspect of the invention, from 4 to 24 “lines” or “curves” of adjacent cells may be formed in the ground-engaging element structure 240 (and in some examples, from 6-20 lines or curves of adjacent cells or even from 8-16 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 2 to 16 cells, and in some examples, from 2 to 12 cells or from 2-10 cells.

(35) More specifically, and referring to FIG. 4B (which is a view similar to FIG. 3B), the ground-facing surface 248G of the ground-engaging component 240 is shown with additional lines to highlight certain cell features that may be present in at least some example structures according to the invention. For example, this illustrated matrix structure 250 defines several sets of at least partially open cells (meaning open cells 252 and/or partially open cells 254), 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. 4B at alignment lines 400A-400M. Notably, while not a requirement for any or all “sets” of three or more aligned cells, the “alignment lines” 400A-400M shown in this illustrated example extend from a rear lateral direction toward a forward medial direction of the ground-engaging component 240 and/or the sole structure 204 (and not necessarily in the direct transverse direction). If desired, any one or more sets of cells may be aligned along a line that extends from the rear lateral direction toward the forward medial direction of the ground-engaging component 240 and/or sole structure 204. 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 244 along lines 400A-440M provide and help define lines of flex that extend at least partially across the sole structure 204 and/or the ground-engaging component 240 from the lateral side to the medial side direction and help the ground-engaging component 240 bend with the foot as the wearer rolls the foot forward for the toe-off phase of a step cycle. Notably, the aligned cells shown by alignment line 400K also may be substantially aligned or highly substantially aligned with the middle medial and lateral side primary cleat components 262 and/or their associated mount areas 260, as shown in FIG. 4B.

(36) FIG. 4B further shows sets of adjacent cells located along one or more lines or curves 402A-402F that extend in the generally forward-to-rear direction of the ground-engaging component 240 and/or the sole structure 204. One or more of the lines or curves 402A-402F may be oriented so that their concave surface (if any) faces the medial side of the ground-engaging component 240 and/or sole structure 204 and so that their convex surface (if any) faces the lateral side of the ground-engaging component 240 and/or sole structure 204. The lines or curves 402A-402F are generally gently and smoothly curved or relatively linear. While six generally front-to-back sets of adjacent at least partially open cells are shown as lines or curves 402A-402F in FIG. 4B, more or fewer sets could be provided, if desired. As a more specific example, from one to six linear or curved sets of adjacent at least partially open cells 402A-402F could be provided across the ground-engaging component 240 and/or sole structure 204, and each of these sets of cells 402A-402F may include from 4-18 cells, and in some examples, from 6-15 cells, or from 8-12 cells. These sets of adjacent at least partially open cells 402A-402F 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 244 along lines or curves 402A-402F 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 240 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.

(37) As shown by FIGS. 2B, 3A, 3B, 4A, 4B, and 4C, in these illustrated example ground-engaging components 240, an average open cell 252 size defined by the matrix structure 250 on a medial forefoot side support area of the ground-engaging component 240 is smaller than an average open cell 252 size defined by the matrix structure 250 on a lateral forefoot side support area of the ground-engaging component 240. This same medial size area to lateral size area differential may apply through at least a portion of the arch support area as well. Compare, for example: (a) the areas of the open cells (e.g., cell opening areas) along curve 402A and those toward the medial side with (b) the areas of the open cells (e.g., cell opening areas) along curve 402B and those toward the lateral side. Also, as further shown in these figures, an average open cell 252 size defined by the matrix structure 250 in a first metatarsal head support area (“big toe” side) of the ground-engaging component 240 is smaller than an average open cell 252 size defined by the matrix structure 250 in a fourth and/or fifth metatarsal head support area (“little toe” side) of the ground-engaging component 240. The smaller open cells 252 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.

(38) Also, in this same vein, if desired, the matrix structure 250 may define open cell 252 sizes such that an average open cell size (e.g., cell opening area) defined by the matrix structure 250 on a medial side of a longitudinal center line of the ground-engaging component 240 and/or sole structure 204 is smaller than an average open cell size (e.g., cell opening area) defined by the matrix structure 250 on a lateral side of the longitudinal center line. The “longitudinal center line” of a ground-engaging component 240 and/or a sole structure 204 can be found by locating the center points of line segments extending in the transverse direction (see FIG. 1) from the lateral side edge to the medial side edge of the ground-engaging component 240 and/or the sole structure 204 all along the longitudinal length of the component 240/sole structure 204.

(39) As shown in the figures, the medial arch support area and the medial forefoot support area of these example ground-engaging components 240 include several smaller sized open cells. As some more specific examples, either or both of these areas of the matrix structure 250 may include a plurality of open cells 252 having an open area of less than 35 mm.sup.2, and in some examples, a plurality of open cells 252 having an open area of less than 30 mm.sup.2, or even less than 25 mm.sup.2.

(40) Additional potential features of various specific areas of the ground-engaging component 240 now will be described in more detail. As shown in FIG. 4C, in the arch support area and/or the forefoot support area, the matrix structure 250 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 50% (and in some adjacent cell pairs, less than 35% or even less than 25%) 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 240M than is a geographic center of the second (larger) open cell 252B. FIG. 4C further illustrates that the second (larger) open cell 252B is elongated in a medial side-to-lateral side direction and/or the first (smaller) open cell 252A is elongated in a front-to-rear direction. The matrix structure 250 of FIG. 4C includes additional adjacent cell pairs (e.g., 252C, 252D, 252E, and 252F) 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 (e.g., 252A/B, 252C, 252D, 252E, 252E) may lie adjacent one another (e.g., with the smaller cells of the pair (closer to the medial side edge 240M) adjacent one another moving in the front-to-back direction and the larger cells of the pair (further from the medial side edge 240M) adjacent one another moving in the front-to-back direction.

(41) As further shown with respect to the open cells labeled 252A-252F in FIG. 4C, the larger and smaller open cells may be arranged adjacent one another in generally triangular arrangements and/or such that some open cells 252 (or other cells) will have six cells around and adjacent to them. More specifically, the cells 252A-252F (and others) are arranged such that two smaller, adjacent (and closer to the medial side edge 240M) open cells are located adjacent one larger open cell (which is located further from the medial side edge 240M than the two smaller adjacent open cells). Likewise, two larger, adjacent (and further from the medial side edge 240M) open cells are located adjacent one smaller open cell (which is located closer the medial side edge 240M 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. These generally triangular arrangements of cells may be repeated multiple times, e.g., in the forefoot support area and/or arch support area of the matrix structure 250.

(42) FIGS. 5A through 5H are provided to help illustrate potential features of the matrix structure 250 and the various cells described above. FIG. 5A provides an enlarged top view showing the upper-facing surface 248U at an area around an open cell 252 defined by the matrix structure 250 (the open space is shown at 244). FIG. 5B shows an enlarged bottom view of this same area of the matrix structure 250 (showing the ground-facing surface 248G). FIG. 5C shows a side view at one leg 502 of the matrix structure 250, and FIG. 5D shows a cross-sectional and partial perspective view of this same leg 502 area. As shown in these figures, the matrix structure 250 provides a smooth top (upper-facing) surface 248U but a more angular ground-facing surface 248G. More specifically, at the ground-facing surface 248G, the matrix structure 250 defines a generally hexagonal ridge 504 around the open cell 252, with the corners 504C of the hexagonal ridge 504 located at a junction area between three adjacent cells in the generally triangular arrangement (the junction of the open cell 252 and two adjacent cells 252J, which may be open, partially open, and/or closed cells, in this illustrated example).

(43) As further shown in these figures, along with FIG. 5E (which shows a sectional view along line 5E-5E of FIG. 5B), the side walls 506 between the upper-facing surface 248U at cell perimeter 244P and the ground-facing surface 248G, which ends at ridge 504 in this example, are sloped. Thus, the overall matrix structure 250, at least at some locations between the generally hexagonal ridge 504 corners 504C, may have a triangular or generally triangular shaped cross section (e.g., see FIGS. 5D and 5E). Moreover, as shown in FIGS. 5C and 5D, the generally hexagonal ridge 504 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 506 may have a planar surface (e.g., like shown in FIG. 5H), 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. 5E), or a partially curved surface (e.g., curved along some of its height dimension Z).

(44) The raised corners 504C of the generally hexagonal ridge 504 in this illustrated example ground-engaging component 240 may be formed as sharp peaks that may act as secondary traction elements at desired locations around the ground-engaging component 240. As evident from these figures and the discussion above, the generally hexagonal ridges 504 and side walls 506 from three adjacent cells (e.g., 252 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, 506 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, 506), which can function as a secondary traction element when it contacts the ground in use. This same type of pyramid structure formed by matrix 250 also may be used to form the secondary traction elements 264 at cleat support areas 260.

(45) Not every cell (open, partially open, or closed) in the ground-engaging component 240 needs to have this type of secondary traction element structure (e.g., with raised pointed pyramids at the generally hexagonal ridge 504 corners 504C), and in fact, not every generally hexagonal ridge 504 corner 504C around a single cell 252 needs to have a raised secondary traction element structure. One or more of the ridge components 504 of a given cell 252 may have a generally straight line structure along the ground-facing surface 248G 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 240 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 250, e.g., anywhere along ridge 504 or between adjacent cells. As some more specific examples, a portion of the arch support area (e.g., area 410 in FIG. 4D) and a portion of the central forefoot area (e.g., area 412 in FIG. 4D) may have no or less prominent secondary traction elements, while other areas (e.g., the heel support area 414, the medial arch/forefoot area (e.g., including clusters 280A-280C in FIG. 4D), the forward toe area 418, and/or the lateral forefoot/arch side support area 420) may include the secondary traction elements (or more pronounced secondary traction elements).

(46) Notably, in this example construction, the matrix structure 250 defines at least some of the cells 252 (and 252J) such that the perimeter of the entrance to the cell opening 252 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 252 around the ground-facing surface 248G (e.g., defined by the generally hexagonal perimeter ridge 504). Stated another way, the area of the entrance to the cell opening 252 from the upper-facing surface 248U (e.g., the area within the perimeter 244P of the ovoid shaped opening) is smaller than the area of the entrance to the cell opening 252 from the ground-facing surface 248G (e.g., the area within the generally hexagonal perimeter ridge 504). The generally hexagonal perimeter ridge 504 completely surrounds the perimeter 244P in at least some cells. This difference in the entrance areas and sizes is due to the sloped/curved sides walls 506 from the upper-facing surface 248U to the ground-facing surface 248G.

(47) FIGS. 5F through 5H show views similar to those in FIGS. 5A, 5B, and 5E but with a portion of the matrix structure 250 originating in the outer perimeter boundary rim 242O (and thus the cell is a partially open cell 254). As shown in FIG. 5G, in this illustrated example, the matrix structure 250 morphs outward and downward from the ground-facing surface 248G of the outer perimeter boundary rim 242O. This may be accomplished, for example, by molding the matrix structure 250 as an unitary, one-piece component with the outer perimeter boundary rim member 242O. Alternatively, the matrix structure 250 could be formed as a separate component that is fixed to the outer perimeter boundary rim member 242O, e.g., by cements or adhesives, by mechanical connectors, etc. As another option, the matrix structure 250 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. 5F-5H may have any one or more of the various characteristics, options, and/or features of the similar structures and parts shown in FIGS. 5A-5E (and like reference numbers in these figures represent the same or similar parts to those used in other figures).

(48) As noted above, in at least some examples of this invention, the matrix structure 250 may define smaller cell sizes on the medial side as compared to the lateral side of a longitudinal center line. Also, as described above, the matrix structure 250 may define secondary traction elements at corners 504C of the matrix structure 250 (e.g., as three sided pyramids). Thus, as illustrated in FIG. 4D, in some examples of this invention, the matrix structure 250 will define one or more clusters 280A-280C of at least ten secondary traction elements at corners 504C (and in some examples, at least 12 secondary traction elements at corners 504C) located within a 35 mm diameter circle (and in some examples, within a 30 mm diameter circle or within a 25 mm diameter circle) at one or more locations in the matrix structure 250. For example, FIG. 4D illustrates one cluster 280A located along a medial side of the ground-engaging component 240 rearward of a first metatarsal head support area and forward of a heel support area of the ground-engaging component 240 (e.g., in an arch support area). Another such cluster 280B is shown on the medial side and forward of the previously identified cluster 280A (e.g., near the rearmost medial primary cleat 262). Yet another such cluster 280C is shown on the medial side and forward of the previously identified clusters 280A, 280B (e.g., between the rearmost medial primary cleat 262 and the middle primary cleat 262). More or fewer such clusters could be provided, optionally at other locations in the ground-engaging component 240 structure. These clusters 280A-280C may be used to provide increased stiffness or support at those local areas.

II. CONCLUSION

(49) The present invention is disclosed above and in the accompanying drawings with reference to a variety of embodiments and/or options. The purpose served by the disclosure, however, is to provide examples of various features and concepts related to the invention, not to limit the scope of the invention. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the features of the invention described above without departing from the scope of the present invention, as defined by the appended claims.

(50) For the avoidance of doubt, the present application includes the subject-matter described in the following numbered paragraphs (referred to as “para.” or “paras.”): [Para. 1] A ground-engaging component for an article of footwear, comprising: 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, wherein the outer perimeter boundary rim defines an open space at least at a forefoot support area of the ground-engaging component, wherein the outer perimeter boundary rim is shaped such that the outer perimeter of the ground-engaging component tapers or curves inward moving from a forefoot support area to an arch support area, and wherein a first width dimension from a lateral side edge to a medial side edge of the outer perimeter boundary rim in a central heel support area of the ground-engaging component is less than a second width dimension from the lateral side edge to the medial side edge in the arch support area; and a support structure extending from the outer perimeter boundary rim and across the open space. [Para. 2] The ground-engaging component according to Para. 1, wherein the support structure includes a matrix structure extending from the outer perimeter boundary rim 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. [Para. 3] The ground-engaging component according to Para. 2, wherein at least 60% of the open cells of the open cellular construction have curved perimeters with no distinct corners. [Para. 4] The ground-engaging component according to Para. 2 or Para. 3, wherein the matrix structure further defines a first cleat support area at or at least partially within the ground-facing surface of the outer perimeter boundary rim. [Para. 5] The ground-engaging component according to Para. 4, further comprising: a track spike engaged at the first cleat support area. [Para. 6] The ground-engaging component according to Para. 4 or Para. 5, wherein the matrix structure further defines a plurality of secondary traction elements dispersed around the first cleat support area. [Para. 7] The ground-engaging component according to Para. 2 or Para. 3, wherein the matrix structure further defines: a first cleat support area at or at least partially in a lateral side of the ground-facing surface of the outer perimeter boundary rim; a second cleat support area at or at least partially in the lateral side of the ground-facing surface of the outer perimeter boundary rim and located forward of the first cleat support area; a third cleat support area at or at least partially in a medial side of the ground-facing surface of the outer perimeter boundary rim; and a fourth cleat support area at or at least partially in the medial side of the ground-facing surface of the outer perimeter boundary rim and located forward of the third cleat support area. [Para. 8] The ground-engaging component according to Para. 7, further comprising a first track spike engaged at the first cleat support area, a second track spike engaged at the second cleat support area, a third track spike engaged at the third cleat support area, and a fourth track spike engaged at the fourth cleat support area. [Para. 9] The ground-engaging component according to Para. 7, wherein the matrix structure further defines: a fifth cleat support area at or at least partially in the lateral side of the ground-facing surface of the outer perimeter boundary rim and located forward of the second cleat support area; and a sixth cleat support area at or at least partially in the medial side of the ground-facing surface of the outer perimeter boundary rim and located forward of the fourth cleat support area. [Para. 10] The ground-engaging component according to Para. 9, further comprising a first track spike engaged at the first cleat support area, a second track spike engaged at the second cleat support area, a third track spike engaged at the third cleat support area, a fourth track spike engaged at the fourth cleat support area, a fifth track spike engaged at the fifth cleat support area, and a sixth track spike engaged at the sixth cleat support area. [Para. 11] The ground-engaging component according to any one of Paras. 2 through 10, wherein an average open cell size defined by the matrix structure on a medial forefoot side support area of the ground-engaging component is smaller than an average open cell size defined by the matrix structure on a lateral forefoot side support area of the ground-engaging component. [Para. 12] The ground-engaging component according to any one of Paras. 2 through 10, wherein an average open cell size defined by the matrix structure in a first metatarsal head support area of the ground-engaging component is smaller than an average open cell size defined by the matrix structure in a fourth and fifth metatarsal head support area of the ground-engaging component. [Para. 13] The ground-engaging component according to any one of Paras. 2 through 10, wherein an average open cell size defined by the matrix structure on a medial side of a longitudinal center line of the ground-engaging component is smaller than an average open cell size defined by the matrix structure on a lateral side of the longitudinal center line. [Para. 14] The ground-engaging component according to any one of Paras. 2 through 10, wherein the matrix structure defines a plurality of open cells having an open area of less than 25 mm.sup.2 in a medial arch support area. [Para. 15] The ground-engaging component according to any one of Paras. 2 through 10, wherein the matrix structure defines a cluster of at least ten secondary traction elements within a 30 mm diameter circle at a location along a medial side of the ground-engaging component rearward of a first metatarsal head support area of the ground-engaging component and forward of a heel support area of the ground-engaging component. [Para. 16] The ground-engaging component according to any one of Paras. 2 through 10, wherein the matrix structure defines a first cluster of at least ten secondary traction elements within a 30 mm diameter circle at a first location along a medial side of the ground-engaging component rearward of a first metatarsal head support area of the ground-engaging component and forward of a heel support area of the ground-engaging component; and a second cluster of at least ten secondary traction elements within a 30 mm diameter circle at a second location along the medial side of the ground-engaging component rearward of the first cluster and forward of the heel support area of the ground-engaging component. [Para. 17] The ground-engaging component according to any one of Paras. 2 through 10, wherein in the arch support area or the forefoot support area, the matrix structure defines a first open cell and an adjacent second open cell, wherein the first open cell has an opening with a cross sectional area of less than 50% of a cross sectional area of an opening of the second open cell, and wherein a geographic center of the first open cell is located closer to the medial side edge than is a geographic center of the second open cell. [Para. 18] The ground-engaging component according to Para. 17, wherein the cross sectional area of the opening of the first open cell is less than 25% of the cross sectional area of the opening of the second open cell. [Para. 19] The ground-engaging component according to Para. 17 or Para. 18, wherein the second open cell is elongated in a medial side-to-lateral side direction. [Para. 20] The ground-engaging component according to any one of Paras. 17 through 19, wherein the first open cell is elongated in a front-to-rear direction. [Para. 21] The ground-engaging component according to any one of Paras. 17 through 20, wherein in the arch support area or the forefoot support area, the matrix structure further defines a third open cell and an adjacent fourth open cell, wherein the third open cell has an opening with a cross sectional area of less than 50% of a cross sectional area of an opening of the fourth open cell, and wherein a geographic center of the third open cell is located closer to the medial side edge than is a geographic center of the fourth open cell. [Para. 22] The ground-engaging component according to Para. 21, wherein the cross sectional area of the opening of the third open cell is less than 25% of the cross sectional area of the opening of the fourth open cell. [Para. 23] The ground-engaging component according to Para. 21 or Para. 22, wherein the fourth open cell is elongated in the medial side-to-lateral side direction. [Para. 24] The ground-engaging component according to any one of Paras. 21 through 23, wherein the third open cell is elongated in a front-to-rear direction. [Para. 25] The ground-engaging component according to any one of Paras. 21 through 24, wherein the first open cell is adjacent the third open cell and the second open cell is adjacent the fourth open cell. [Para. 26] The ground-engaging component according to any one of Paras. 21 through 24, wherein in the arch support area or the forefoot support area, the matrix structure further defines a fifth open cell and an adjacent sixth open cell, wherein the fifth open cell has an opening with a cross sectional area of less than 50% of a cross sectional area of an opening of the sixth open cell, and wherein a geographic center of the fifth open cell is located closer to the medial side edge than is a geographic center of the sixth open cell. [Para. 27] The ground-engaging component according to Para. 26, wherein in the arch support area or the forefoot support area, the matrix structure further defines a seventh open cell and an adjacent eighth open cell, wherein the seventh open cell has an opening with a cross sectional area of less than 50% of a cross sectional area of an opening of the eighth open cell, and wherein a geographic center of the seventh open cell is located closer to the medial side edge than is a geographic center of the eighth open cell. [Para. 28] The ground-engaging component according to any preceding Para., wherein the outer perimeter boundary rim and the support structure have a combined mass of less than 40 grams. [Para. 29] The ground-engaging component according to any preceding Para., wherein the ground-engaging component has a width dimension of no more than 1.75 inches within its rearmost 2 inches, wherein the width dimension is a dimension from the lateral side edge of the outer perimeter boundary rim directly to the medial side edge of the outer perimeter boundary rim. [Para. 30] The ground-engaging component according to Para. 29, wherein the width dimension is no more than 1.5 inches within the rearmost 2 inches of the ground-engaging component. [Para. 31] The ground-engaging component according to Para. 29, wherein the width dimension is no more than 1.5 inches within a rearmost 3 inches of the ground-engaging component. [Para. 32] The ground-engaging component according to any preceding Para., wherein the outer perimeter boundary rim is at least 4 mm wide. [Para. 33] The ground-engaging component according to any preceding Para., wherein the outer perimeter boundary rim is present around at least 80% of the outer perimeter of the ground-engaging component. [Para. 34] An article of footwear, comprising: an upper; and a sole structure engaged with the upper, wherein the sole structure includes a ground-engaging component according to any preceding Para. [Para. 35] The article of footwear according to Para. 34, wherein at least a portion of the upper includes at least one of a woven textile component or a knitted textile component. [Para. 36] The article of footwear according to Para. 34 or 35, wherein the sole structure further includes a midsole component between the ground-engaging component and a bottom of the upper. [Para. 37] The article of footwear according to Para. 36, wherein the midsole component includes a foam midsole element. [Para. 38] The article of footwear according to Para. 36 or Para. 37, wherein a bottom surface of the midsole component is exposed at an exterior of the sole structure. [Para. 39] The article of footwear according to Para. 38, wherein the bottom surface of the midsole component is exposed through at least some open cells of any matrix structure provided as part of the ground-engaging component. [Para. 40] The article of footwear according to Para. 36 or Para. 37, wherein a bottom surface of the midsole component is exposed at an exterior of the sole structure and extends outside of the outer perimeter boundary rim of the ground-engaging component at least at a heel support area of the sole structure. [Para. 41] The article of footwear according to Para. 40, wherein the bottom surface of the midsole component is exposed through at least some open cells of any matrix structure provided as part of the ground-engaging component.