SOLE STRUCTURE HAVING AN OUTSOLE WITH INTEGRATED TRACTION ELEMENTS

[0001] This application claims priority to, and the benefit of, U.S. Provisional Patent Application 63/104,617, filed on Oct. 23, 2020, the entire disclosure of which is hereby incorporated by reference.

[0002] The present teachings generally relate to a sole structure for an article of footwear and, more particularly, to a footwear sole structure having an outsole with integrated traction elements.

[0003] This section provides background information related to the present disclosure which is not necessarily prior art.

[0004] Articles of footwear include an upper and a sole structure. The upper may be formed from any suitable material(s) to receive, secure, and support a foot on the sole structure. The upper may cooperate with laces, straps, or other fasteners to adjust the fit of the upper around the foot. A bottom portion of the upper, proximate to a bottom surface of the foot, attaches to the sole structure.

[0005] Sole structures include a layered arrangement extending between a ground surface and the upper. One layer of the sole structure includes an outsole that provides abrasion-resistance and traction with the ground surface. The outsole may be formed from rubber or other materials that impart durability and wear-resistance, as well as enhancing traction with the ground surface. Another layer of the sole structure includes a midsole disposed between the outsole and the upper. The midsole provides cushioning for the foot and is at least partially formed from a polymer foam material that compresses resiliently under an applied load to cushion the foot by attenuating ground-reaction forces. The midsole may define a bottom surface on one side that opposes the outsole and a footbed on the opposite side that may be contoured to conform to a profile of the bottom surface of the foot. Sole structures may also include a comfort-enhancing insole or a sockliner located within a void proximate to the bottom portion of the upper.

[0006] The metatarsophalangeal (MTP) joint of the foot is known to absorb energy as it flexes through dorsiflexion during running movements. As the foot does not move through plantarflexion until the foot is pushing off of a ground surface, the MTP joint returns little of the energy it absorbs to the running movement and, thus, is the source of an energy drain during running movements. Embedding flat and rigid plates having longitudinal stiffness within a sole structure increases the overall stiffness thereof.

[0020] The present disclosure describes an article of footwear. In an aspect of the present disclosure, the sole structure includes an outsole including an outsole plate and a plurality of traction elements molded to the outsole plate. Each of the plurality of traction elements includes a plurality of overhangs, each of the plurality of overhangs is cantilevered from the outsole plate. The sole structure further includes a midsole disposed over the outsole. The midsole includes a plurality of discrete pods. Each of the plurality of discrete pods includes a midsole fluid-filled bladder. The midsole fluid-filled bladder defines an interior cavity. The midsole fluid-filled bladder includes a first polymeric layer, a second polymeric layer, and a plurality of midsole tethers interconnecting the first polymeric layer and the second polymeric layer, each of the plurality of midsole tethers is disposed in the interior cavity of the midsole fluid-filled bladder. Each of the plurality of discrete pods is disposed over and aligned with one of the plurality of traction elements to maximize an energy efficiency of the sole structure.

[0021] The outsole may be made of thermoplastic polyurethane. The thermoplastic polyurethane has a hardness measured in Shore A. The hardness of the thermoplastic polyurethane may be between 85 and 95 to promote flexion of the sole structure. The sole structure may further include a foam layer and a strobel disposed over the foam layer. The foam layer may be disposed between the strobel and the plurality of discrete pods. The strobel may include a strobel fluid-filled bladder, and the strobel fluid-filled bladder includes a first strobel layer, a second strobel layer, and a plurality of strobel tethers interconnecting the first strobel layer and the second strobel layer.

[0022] The plurality of traction elements may include solely three traction elements. The outsole has a forefoot region, a heel region, and a midfoot region disposed between the forefoot region and the heel region. The plurality of traction elements may solely include a first forefoot traction element, a second forefoot traction element, and a heel traction element. The first forefoot traction element and the second forefoot traction element are disposed in the forefoot region of the outsole. The heel traction element is disposed in the heel region of the outsole. None of the plurality of traction elements is disposed in the midfoot region of the outsole.

[0023] The heel traction element may cover a majority of the heel region of the outsole, and the heel traction element is larger than the first forefoot traction element and the second forefoot traction element. The adjacent overhangs of the plurality of overhangs of each of the plurality of traction elements may be spaced apart from one another by a void. The void between the adjacent overhangs may define an acute angle from one of the adjacent overhangs to another of the adjacent overhangs to facilitate flexion along predefined flex lines.

[0024] In an aspect of the present disclosure, an article of footwear includes an upper and a sole structure coupled to the upper. The sole structure includes an outsole including an outsole plate and a plurality of traction elements molded to the outsole plate. Each of the plurality of traction elements includes a plurality of overhangs. Each of the plurality of overhangs is cantilevered from the outsole plate. The sole structure further includes a midsole disposed over the outsole. The midsole includes a plurality of discrete pods. Each of the plurality of discrete pods includes a midsole fluid-filled bladder. The midsole fluid-filled bladder defines an interior cavity. The midsole fluid-filled bladder includes a first polymeric layer and a second polymeric layer. The midsole includes a plurality of midsole tethers interconnecting the first polymeric layer and the second polymeric layer. Each of the plurality of midsole tethers is disposed in the interior cavity of the midsole fluid-filled bladder. Each of the plurality of discrete pods is disposed over and aligned with one of the plurality of traction elements to maximize the energy efficiency of the sole structure.

[0025] The outsole may be made of thermoplastic polyurethane. The thermoplastic polyurethane has a hardness measured in Shore A. The hardness of the thermoplastic polyurethane is between 85 and 95 to promote flexion of the sole structure. The article of footwear may further include a foam layer and a strobel disposed over the foam layer. The foam layer is disposed between the strobel and the plurality of discrete pods.

[0026] The strobel may include a strobel fluid-filled bladder. The strobel fluid-filled bladder may include a first strobel layer, a second strobel layer, and a plurality of strobel tethers interconnecting the first strobel layer and the second strobel layer.

[0027] The article of footwear may further a string having a first string terminus and a second string terminus opposite the first string terminus. The first string terminus is directly coupled to the midsole, and the second string terminus is configured to be directly coupled to an upper.

[0028] The plurality of traction elements may solely include three traction elements. The outsole has a forefoot region, a heel region, and a midfoot region disposed between the forefoot region and the heel region. The plurality of traction elements may solely include a first forefoot traction element, a second forefoot traction element, and a heel traction element. The first forefoot traction element and the second forefoot traction element are disposed in the forefoot region of the outsole. The heel traction element may be disposed in the heel region of the outsole. None of the plurality of traction elements is disposed in the midfoot region of the outsole.

[0029] The heel traction element may cover a majority of the heel region of the outsole. The heel traction element is larger than the first forefoot traction element and the second forefoot traction element. Adjacent overhangs of the plurality of overhangs of each of the plurality of traction elements may be spaced apart from one another by a void. The void between the adjacent overhangs may define an acute angle from one of the adjacent overhangs to another of the adjacent overhangs to facilitate flexion along predefined flex lines.

[0030] The present disclosure also describes a method of manufacturing an outsole. The method includes injecting a molten polymeric material into a mold cavity of a mold. The mold includes a mold body and a plurality of inserts detachably coupled to the mold body. The mold body defines the mold cavity. The mold cavity is shaped as the outsole. The plurality of inserts is shaped to form a plurality of gaps between an outsole plate of the outsole and each of a plurality of traction elements of the outsole. The method further includes cooling the polymeric material until the polymeric material solidifies and removing the plurality of inserts from the polymeric material after the polymeric material solidifies to form the plurality of gaps.

[0031] Removing the plurality of inserts may include hand picking the inserts from the polymeric material after the polymeric material solidifies. Removing the plurality of inserts may include applying a magnetic field toward the plurality of inserts to withdraw the plurality of inserts from the polymeric material after the polymeric material solidifies.

[0032] The present disclosure also describes a sole structure including an outsole. The outsole has a forefoot region, a heel region, and a midfoot region disposed between the forefoot region and the heel region. The outsole includes an outsole plate and a plurality of traction elements molded to the outsole plate. Each of the plurality of traction elements includes a plurality of overhangs. Each of the plurality of overhangs is cantilevered from the outsole plate. The plurality of traction elements may include at least a first forefoot traction element, a second forefoot traction element, and a heel traction element. The first forefoot traction element and the second forefoot traction element are disposed in the forefoot region of the outsole, and the heel traction element is disposed in the heel region of the outsole.

[0033] The outsole may be made of thermoplastic polyurethane. The thermoplastic polyurethane has a hardness measured in Shore A, and the hardness of the thermoplastic polyurethane may be between 85 and 95 to promote flexion of the sole structure.

[0034] Adjacent overhangs of the plurality of overhangs of each of the plurality of traction elements may be spaced apart from one another by a void. The void between the adjacent overhangs may define an acute angle from one of the adjacent overhangs to another of the adjacent overhangs to facilitate flexion along predefined flex lines. The heel traction element may cover the majority of the heel region of the outsole, and the heel traction element is larger than the first forefoot traction element and the second forefoot traction element. The outsole plate may extend through the forefoot region, the heel region, and the midfoot region of the outsole.

[0035] The above features and advantages and other features and advantages of the present teachings are readily apparent from the following detailed description of the modes for carrying out the present teachings when taken in connection with the accompanying drawings.

[0036] Example configurations will now be described more fully with reference to the accompanying drawings. Example configurations are provided so that this disclosure will be thorough, and will fully convey the scope of the disclosure to those of ordinary skill in the art. Specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of configurations of the present disclosure. It will be apparent to those of ordinary skill in the art that specific details need not be employed, that example configurations may be embodied in many different forms, and that the specific details and the example configurations should not be construed to limit the scope of the disclosure.

[0037] To assist and clarify the description of various embodiments, various terms are defined herein. Unless otherwise indicated, the following definitions apply throughout this specification (including the claims). Additionally, all references referred to are incorporated herein in their entirety.

[0038] An “article of footwear”, a “footwear article of manufacture”, and “footwear” may be considered to be both a machine and a manufacture. Assembled, ready to wear footwear articles (e.g., shoes, sandals, boots, etc.), as well as discrete components of footwear articles (such as a midsole, an outsole, an upper component, etc.) prior to final assembly into ready to wear footwear articles, are considered and alternatively referred to herein in either the singular or plural as “article(s) of footwear” or “footwear”.

[0039] “A”, “an”, “the”, “at least one”, and “one or more” are used interchangeably to indicate that at least one of the items is present. A plurality of such items may be present unless the context clearly indicates otherwise. All numerical values of parameters (e.g., of quantities or conditions) in this specification, unless otherwise indicated expressly or clearly in view of the context, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters. As used in the description and the accompanying claims, unless stated otherwise, a value is considered to be “approximately” equal to a stated value if it is neither more than 5 percent greater than nor more than 5 percent less than the stated value. In addition, a disclosure of a range is to be understood as specifically disclosing all values and further divided ranges within the range.

[0040] The terms “comprising”, “including”, and “having” are inclusive and therefore specify the presence of stated features, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, or components. Orders of steps, processes, and operations may be altered when possible, and additional or alternative steps may be employed. As used in this specification, the term “or” includes any one and all combinations of the associated listed items. The term “any of” is understood to include any possible combination of referenced items, including “any one of” the referenced items. The term “any of” is understood to include any possible combination of referenced claims of the appended claims, including “any one of” the referenced claims.

[0041] For consistency and convenience, directional adjectives may be employed throughout this detailed description corresponding to the illustrated embodiments. Those having ordinary skill in the art will recognize that terms such as “above”, “below”, “upward”, “downward”, “top”, “bottom”, etc., may be used descriptively relative to the figures, without representing limitations on the scope of the invention, as defined by the claims.

[0042] The term “longitudinal” refers to a direction extending along a length of a component. For example, a longitudinal direction of an article of footwear extends between a forefoot region and a heel region of the article of footwear. The term “forward” or “anterior” is used to refer to the general direction from a heel region toward a forefoot region, and the term “rearward” or “posterior” is used to refer to the opposite direction, i.e., the direction from the forefoot region toward the heel region. In some cases, a component may be identified with a longitudinal axis as well as a forward and rearward longitudinal direction along that axis. The longitudinal direction or axis may also be referred to as an anterior-posterior direction or axis.

[0043] The term “transverse” refers to a direction extending along a width of a component. For example, a transverse direction of an article of footwear extends between a lateral side and a medial side of the article of footwear. The transverse direction or axis may also be referred to as a lateral direction or axis or a mediolateral direction or axis.

[0044] The term “vertical” refers to a direction generally perpendicular to both the lateral and longitudinal directions. For example, in cases where a sole structure is planted flat on a ground surface, the vertical direction may extend from the ground surface upward. It will be understood that each of these directional adjectives may be applied to individual components of a sole structure. The term “upward” or “upwards” refers to the vertical direction pointing towards a top of the component, which may include an instep, a fastening region, and/or a throat of an upper. The term “downward” or “downwards” refers to the vertical direction pointing opposite the upwards direction, toward the bottom of a component and may generally point towards the bottom of a sole structure of an article of footwear.

[0045] The “interior” of an article of footwear, such as a shoe, refers to portions at the space that is occupied by a wearer's foot when the article of footwear is worn. The “inner side” of a component refers to the side or surface of the component that is (or will be) oriented toward the interior of the component or article of footwear in an assembled article of footwear. The “outer side” or “exterior” of a component refers to the side or surface of the component that is (or will be) oriented away from the interior of the article of footwear in an assembled article of footwear. In some cases, other components may be between the inner side of a component and the interior in the assembled article of footwear. Similarly, other components may be between an outer side of a component and the space external to the assembled article of footwear. Further, the terms “inward” and “inwardly” refer to the direction toward the interior of the component or article of footwear, such as a shoe, and the terms “outward” and “outwardly” refer to the direction toward the exterior of the component or article of footwear, such as the shoe. In addition, the term “proximal” refers to a direction that is nearer a center of a footwear component, or is closer toward a foot when the foot is inserted in the article of footwear as it is worn by a user. Likewise, the term “distal” refers to a relative position that is further away from a center of the footwear component or is further from a foot when the foot is inserted in the article of footwear as it is worn by a user. Thus, the terms proximal and distal may be understood to provide generally opposing terms to describe relative spatial positions.

[0046] The terminology used herein is for the purpose of describing particular exemplary configurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method, steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. Additional or alternative steps may be employed.

[0047] When an element or layer is referred to as being “on,” “engaged to,” “connected to,” “attached to,” or “coupled to” another element or layer, it may be directly on, engaged, connected, attached, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” “directly attached to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

[0048] The terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers, and/or sections. These elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer, or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example configurations.

[0049] Referring to FIGS. 1-3, an article of footwear 100 may be a golf shoe and includes an upper 102 and a sole structure 200, which is partially formed by the upper 102. The article of footwear 100 (and its components, such as the upper 102 and the sole structure 200) may be divided into one or more portions. The portions may include a forefoot portion 12, a midfoot portion 14, and a heel portion 16. The forefoot portion 12 may correspond with toes and joints connecting metatarsal bones with phalanx bones of a foot during use of the footwear 100. The forefoot portion 12 may correspond with the metatarsophalangeal (MTP) joint of the foot. The midfoot portion 14 may correspond with an arch area of the foot, and the heel portion 16 may correspond with rear portions of the foot, including a calcaneus bone, during use of the article of footwear 100. The footwear 100 may include lateral and medial sides 18, 20, respectively, corresponding with opposite sides of the footwear 100 and extending through the portions 12, 14, 16.

[0050] The upper 102 includes interior surfaces that define an interior void 103 (FIG. 2) that receives and secures a foot for support on the sole structure 200, during use of the article of footwear 100. An ankle opening 104 in the heel portion 16 may provide access to the interior void 103. For example, the ankle opening 104 may receive a foot to secure the foot within the interior void 103 and facilitate entry and removal of the foot to and from the interior void 103. In some examples, one or more fasteners 106 extend along the upper 102 to adjust a fit of the interior void 103 around the foot while concurrently accommodating entry and removal of the foot therefrom. The upper 102 may include apertures such as eyelets and/or other engagement features such as fabric or mesh loops that receive the fasteners 106. The fasteners 106 may include laces, straps, cords, hook-and-loop, or any other suitable type of fastener. For example, the fasteners 106 include flexible laces, and the upper 102 further includes a retaining tube 107 coupled to the fasteners 106 (e.g., laces). During use, the wearer of the article of footwear 100 can pull the retaining tube 107 to adjust and tighten the fasteners 106.

[0051] The upper 102 may also include a heel cup 115 at the heel portion 16 to support the heel of the footwear user. The upper 102 may include a tongue portion 110 that extends between the interior void 103 and the fasteners 106. The upper 102 may be formed from one or more materials (i.e., the upper material) that are stitched or adhesively bonded together to form the interior void 103. Suitable materials of the upper may include, but are not limited, textiles, fabrics, foam, leather, and synthetic leather. The materials may be selected and located to impart properties of durability, air-permeability, wear-resistance, flexibility, and comfort. For example, the upper 102 may be wholly or partially made of a waterproof knitted textile to protect the wearer's foot from moisture.

[0052] The sole structure 200 is secured to the upper 102 and is spaced apart from the upper 102 along a vertical direction VT. The sole structure 200 may include a midsole 202 for providing cushioning to the footwear user. To this end, the midsole 202 may be made of a polymeric material, such as rubber or foam. As a non-limiting example, the midsole 202 may be wholly or partially made of an ethylene-vinyl acetate (EVA) foam to enhance cushioning of the sole structure 200. The midsole 202 may continuously extend along the forefoot portion 12, the midfoot portion 14, and the heel portion 16 to provide cushioning to the entire foot of the footwear wearer.

[0053] As a non-limiting example, the midsole 202 may include a foam layer 204 extending through the forefoot portion 12, the midfoot portion 14, and the heel portion 16 to provide cushioning to the entire foot of the footwear wearer. The foam layer 204 may be wholly or partly made of a foam to provide cushioning to the footwear wearer. For example, the foam layer 204 may be wholly or partly made of EVA foam. The midsole 202 may define one or more midsole openings 206 extending through the part or the entire thickness of the foam layer 204. Each of the midsole openings 206 may be configured as thru-holes or recesses. Regardless of the specific configuration, each of the midsole openings 206 is configured, shaped, and sized to receive at least one discrete pod 208, which are described in detail below.

[0054] As discussed above, one or more of the midsole openings 206 may be a thru-hole to enhance the energy efficiency of the midsole 202. Further, the midsole openings 206 may have a hexagonal shape or a substantially hexagonal shape to tightly accommodate each discrete pod 208, thereby preventing the discrete pods 208 from moving lateral or longitudinally relative to the upper 102. By limiting the lateral and longitudinal movement of the discrete pods 208 relative to the upper 102, the energy efficiency of the discrete pods 208 can be enhanced.

[0055] In order to simplify manufacturing, the midsole 202 may solely include three midsole openings 206, namely: a first midsole opening 206a, a second midsole opening 206b, and a third midsole opening 206c. The first midsole opening 206a and the second midsole opening 206b are entirely located in the forefoot portion 12, whereas the third midsole opening 206c is entirely located in heel portion 16. The third midsole opening 206c is spaced apart from the first midsole opening 206a and the second midsole opening 206b along a longitudinal direction LG. The first midsole opening 206a is spaced apart from the second midsole opening 206b along the longitudinal direction LG and the lateral direction LT. The lateral direction LT is perpendicular to the longitudinal direction LG and the vertical direction VT. Each of the first midsole opening 206a, the second midsole opening 206b, and the third midsole opening 206c has a respective opening center, namely: the first opening center 207a, the second opening center 207b, and the third opening center 207c. A first central axis 209a intersects the first opening center 207a of the first midsole opening 206a. A second central axis 209b intersects the second opening center 207b of the second midsole opening 206b. A third central axis 209c intersects the third opening center 207c of the third midsole opening 206c. Each of the first central axis 209a, the second central axis 209b, and the third central axis 209c is parallel with the vertical direction VT. Because each of the midsole openings 206 receives one of the discrete pods 208, the location of the midsole openings 206 as described above assist in enhancing the energy efficiency of the sole structure 200 during the heel strike and the toe-off of the gait cycle. No midsole opening 206 or discrete pod 208 is located in the midfoot portion 14 of the sole structure 200 to minimize costs and facilitate manufacturing of the article of footwear 100.

[0056] In order to simplify manufacturing, the midsole 202 may include solely three discrete pods 208, namely: a first discrete pod 208a, a second discrete pod 208b, and a third discrete pod 208c. It is contemplated, however, that the midsole 202 may include more or fewer discrete pods 208. The first discrete pod 208a and the second discrete pod 208b are entirely located in the forefoot portion 12, whereas the third discrete pod 208c is entirely located in heel portion 16. The third discrete pod 208c is spaced apart from the first discrete pod 208a and the second discrete pod 208b along the longitudinal direction LG. The first discrete pod 208a is spaced apart from the second discrete pod 208b along the longitudinal direction LG and the lateral direction LT. Each of the first discrete pod 208a, the second discrete pod 208b, and the third discrete pod 208c has a respective pod center, namely: the first pod center 212a, the second pod center 212b, and the third pod center 212c. The first central axis 209a intersects the first opening center 207a of the first midsole opening 206a and the first pod center 212a of the first discrete pod 208a to tightly fit the first discrete pod 208a in the first midsole opening 206a. The second central axis 209b intersects the second opening center 207b of the second midsole opening 206b and the second pod center 212b of the second discrete pod 208b to tightly fit the second discrete pod 208b in the second midsole opening 206b. The third central axis 209c intersects the third opening center 207c of the third midsole opening 206c and the third pod center 212c of the third discrete pod 208c to tightly fit the third discrete pod 208c in the third midsole opening 206c. Each of the first central axis 209a, the second central axis 209b, and the third central axis 209c is parallel with the vertical direction VT as discussed above. Because each of the midsole openings 206 receives one of the discrete pods 208, the location of the midsole openings 206 as described above assist in enhancing the energy efficiency of the sole structure 200 during the heel strike and the toe-off of the gait cycle. No discrete pod 208 is located in the midfoot portion 14 of the sole structure 200 to minimize costs and facilitate manufacturing of the article of footwear 100. It is envisioned, however, that one or more discrete pods 208 may be located in the midfoot portion 14 of the sole structure 200. Further, the discrete pods 208 are not necessarily encased. Moreover, the discrete pods 208 may be exposed. As such, the discrete pods 208 may be visible from the bottom of the sole structure 200.

[0057] The article of footwear 100 may further include one or more strings 108 interconnected between the upper 102 and the midsole 202 to enhance the connection between the upper 102 and the midsole 202. As a non-limiting example, the article of footwear 100 includes a plurality of strings 108 each directly connected to the upper 102 and directly connected to the midsole 202 to enhance the structure integrity of the connection between the upper 102 and the midsole 202. For example, each of the strings 108 has a first string terminus 108a and a second string terminus 108b opposite the first string terminus 108a. The first string terminus 108a is directly coupled to the midsole 202, and the second string terminus 108b is directly coupled to the upper 102. Further, one or more of the strings 108 are in tension between the upper 102 and the midsole 202 to enhance the structural integrity of the article of footwear 100. The sole structure 200 further includes an outsole 214 below (and directly connected to the midsole 202).

[0058] The sole structure 200 further includes a strobel board 210 disposed between the midsole 202 and the upper 102. Thus, the strobel board 210 is disposed between the foam layer 204 and the upper 102. Accordingly, the upper 102 is spaced apart from the strobel board 210 along the vertical direction VT, and the midsole 202 is spaced apart from the strobel board 210 along the vertical direction VT. The foam layer 204 is disposed between the strobel board 210 and the discrete pods 208 to provide cushioning to the footwear wearer while maximizing the energy efficiency of the sole structure 200. As described in detail below, the strobel board 210 enhances the energy efficiency of the sole structure 200 and may extend through the forefoot portion 12, the midfoot portion 14, and the heel portion 16 of the sole structure 200 to provide such enhanced energy efficiency throughout the sole structure 200.

[0059] With reference to FIG. 4, each of the discrete pods 208 includes a midsole fluid-filled bladder 230 to provide cushioning to the sole structure 200. The fluid-filled bladder 230 of each of the discrete pods 208 is sealed, thereby preventing fluid from escaping the fluid-filled bladder 230. By maintaining the fluid inside the fluid-filled chamber 230, the cushioning properties of the midsole 202 are preserved. The fluid-filled chamber 230 defines an interior cavity 234. Further, the fluid-filled chamber 230 of each discrete pod 208 includes a first polymeric layer 236 and a second polymeric layer 238 surrounding the interior cavity 234. The first polymeric layer 236 includes a first peripheral edge 240, and the second polymeric layer 238 includes a second peripheral edge 242. The first peripheral edge 240 is directly connected, through for example thermal bonding, to the second peripheral edge 242 sealed a fluid inside the interior cavity 234 of the fluid-filled bladder 230. The fluid-filled bladder 230 may further include one or more midsole tethers 244 interconnecting the first polymeric layer 236 and the second polymeric layer 238 to maintain the first polymeric layer 236 and the second polymeric layer 238 spaced apart from one another when no load is applied to the discrete pod 208, thereby maximizing the energy efficiency of the sole structure 200. As a non-limiting example, each of the midsole tethers 244 are tensioned and directly connected to the first polymeric layer 236 and directly to the second polymeric layer 238 to maximize the energy efficiency of the sole structure 200.

[0060] With reference to FIGS. 5-9, the outsole 214 has an outsole plate 216 and a plurality of traction elements 218 integrally coupled to the outsole plate 216. As such, the outsole plate 216 and the traction elements 218 form a one-piece structure to enhance the structural integrity of the outsole 214. The outsole 214 has a forefoot region 220, a heel region 222, and a midfoot region 224 disposed between the forefoot region 220 and the heel region 222. The outsole 214 has a lateral side 226 and a medial side 228 opposite the lateral side 226. The lateral side 226 is spaced apart from the medial side 228 along the lateral direction LT. The outsole 214 includes treads 231 disposed along forefoot region 220, the midfoot region 224 and the heel region 222 of the outsole plate 216 to enhance traction when the sole structure 200 contacts a ground surface. Each of the treads 231 extends from the lateral side 226 to the medial side 228 of the outsole plate 216 and can be configured as curved ridges and grooves.

[0061] As discussed above, the outsole 214 includes a lip 245 extending upwardly from the forefoot region 220 of the outsole plate 216 to protect the footwear wearer's toes from impacts. In addition to the lip 245, the outsole 214 includes one or more traction elements 218 as discussed above. Regardless of the specific quantity, each of the traction elements 218 is integrally coupled to the outsole plate 216. As such, the traction elements 218 and the outsole plate 216 form a one-piece structure, thereby maximizing the structural integrity of the outsole 214. As a non-limiting example, each of the traction elements 218 is molded to the outsole plate 216. In present disclosure, the term “molded” means that two or more parts are integrally coupled to one another, by a molding process, such that the two or more parts form a one-piece structure. To facilitate traction with a ground surface, the outsole 214 may be wholly or partly made of a thermoplastic polyurethane. The thermoplastic polyurethane may have a hardness (measured in the Shore A scale) that is between 84 and 95 to promote flexion of the sole structure 200.

[0062] As a non-limiting example, the outsole 214 may include solely three traction elements 218 to minimize costs and facilitate manufacturing, namely: a first forefoot traction element 218a, a second forefoot traction element 218b, and a heel traction element 218c. It is envisioned, however, that the outsole 214 may include more or fewer traction elements 218. The first forefoot traction element 218a and the second forefoot traction element 218b are entirely located in the forefoot portion 12, whereas the heel traction element 218c is entirely located in heel portion 16. The heel traction element 218c is spaced apart from the first forefoot traction element 218a and the second forefoot traction element 218b along the longitudinal direction LG. The first forefoot traction element 218a is spaced apart from the second forefoot traction element 218b along the longitudinal direction LG and the lateral direction LT. Each of the first forefoot traction element 218a, the second forefoot traction element 218b, and the heel traction element 218c has a respective pod center, namely: the first traction center 246a, the second traction center 246b, and the third traction center 246c. Each of the discrete pods 208 is disposed over and aligned with one of the traction elements 218 to maximize the energy efficiency of the sole structure 200. For example, the first central axis 209a may intersect the first opening center 207a of the first midsole opening 206a, the first pod center 212a of the first discrete pod 208a, and the first traction center 246 of the first forefoot traction element 218a to maximize the energy efficiency of the sole structure 200. The second central axis 209b may intersect the second opening center 207b of the second midsole opening 206b, the second pod center 212b of the second discrete pod 208b, and the second traction center 246b of the second forefoot traction element 218b to maximize the energy efficiency of the sole structure 200. The third central axis 209c may intersect the third opening center 207c of the third midsole opening 206c, the third pod center 212c of the third discrete pod 208c, and the third traction center 246c of the heel traction element 218c to maximize the energy efficiency of the sole structure 200. No traction element 218 is located in the midfoot portion 14 of the sole structure 200 to minimize costs and facilitate manufacturing of the article of footwear 100.

[0063] The heel traction element 218c covers the majority of the heel region 222 of the outsole 214 and is larger than the first forefoot traction element 218a and the second forefoot traction element 218b to maintain the footwear wearer's foot to stationary during the backswing and downswing of a golf swing. Each of the first traction element 218a and the second forefoot traction element 218b are smaller than the heel traction element 218c and solely cover less than half of the forefoot region 220 of the outsole 214 to maintain the footwear wearer's foot stationary during the backswing and downswing of a golf swing, while allowing rotation of the footwear's foot during the follow-thru state of the golf swing.

[0064] Each of the traction elements 218 includes a plurality of overhangs 248 integrally coupled to the outsole plate 216. As such, the overhangs 248 and the outsole plate 216 form a one-piece structure to enhance the structural integrity of the outsole 214. The overhangs 248 may be referred to as flanges, and each of the overhangs 248 is cantilevered from the outsole plate 216 to enhance the energy efficiency of the sole structure 200. The plurality of overhangs 248 includes a plurality of adjacent overhangs 248p. The adjacent overhangs 248p may be a pair to minimize costs. Each traction element 218 may include solely three pairs of adjacent overhangs 248p to maximize flexion of the sole structure 200, while facilitating manufacturing of the sole structure 200. It is contemplated, however, that the traction elements 218 may include more or fewer overhangs 248. Each pair of adjacent overhangs 248p is spaced apart from another pair of adjacent overhangs 248p by a void 250 to enhance the flexion of the sole structure 200. The void 250 between the pairs of adjacent overhangs 248p may define an acute angle AA to facilitate flexion along predefined flexion lines FL. The acute angle AA is defined from one pair of adjacent overhangs 248p to another pair of adjacent overhangs 248p. All the predefined flexion lines FL intersect a corresponding center of the traction elements 218 (i.e., the first traction center 246a, the second traction center 246b, and the third traction center 246c) to maximize flexion of the sole structure 200.

[0065] As shown in FIGS. 4 and 9, each of the overhangs 248 is obliquely angled relative to outsole plate 216 to form gaps 217 between the outsole plate 216 and the overhangs 248 to enhance the energy efficiency of the outsole 214. For instance, an oblique angle OA (e.g., acute angle) is defined from the outsole plate 216 to the overhang 248 to enhance the energy efficiency of the outsole 214. The outsole plate 216 has a first plate surface 252 and a second plate surface 254 opposite the first plate surface 252. The first plate surface 252 is in direct contact with the midsole 202 to enhance the structural integrity of the sole structure 200, whereas the second plate surface 254 is directly connected to each of the traction elements 218 to enhance the structural integrity of the outsole 214.

[0066] With reference to FIGS. 10 and 11, the strobel board 210 includes one or more strobel fluid-filled bladders 316 wholly or partly made of a polymeric material to enhance the energy efficiency of the sole structure 200. The strobel fluid-filled bladder 316 defines a strobel interior cavity 318 (FIG. 11) and is configured to retain a fluid in the strobel interior cavity 318. The strobel fluid-filled bladder 316 has a peripheral flange 320 extending around at least a portion of a perimeter 321 of the interior cavity 318. In the embodiment shown, the peripheral flange 320 extends around the entire perimeter 321 (e.g., outwardly surrounding the strobel interior cavity 318) generally in an X-Y plane (defined by the X direction and the Y direction) of the strobel fluid-filled bladder 316, where the Z plane (defined by the Z direction) is the height of the strobel fluid-filled bladder 316 from a proximal surface 324 of the strobel fluid-filled bladder 316 to a distal surface 326 of the strobel fluid-filled bladder 316. The peripheral flange 320 extends around a strobel forefoot region 325, a strobel midfoot region 327, and a strobel heel region 329 of the strobel fluid-filled bladder 316.

[0067] The peripheral flange 320 defines a groove 322 extending along the peripheral flange 320. As further discussed herein, the groove 322 serves as a guide path for an operator or for a machine, including a robotic machine. In some of the embodiments shown and described herein, the strobel board 210 is secured to the upper 102 by stitching that extends through the peripheral flange 320. When the strobel board 210 is secured to the upper 102, the strobel board 210 and the upper 102 together define interior void 103. Dynamic compressive loading of the sole structure 200 by a foot in the interior void 103 may cause tension in the strobel board 210 around the peripheral flange 320 in an outward direction, creating a trampoline like effect as the tension is subsequently relieved and strobel tethers 360 of the strobel board 210 return to their tensioned state.

[0068] The strobel fluid-filled bladder 316 includes a first strobel layer 328 and a second strobel layer 330. Each of the first strobel layer 328 and the second strobel layer 330 may be partly or wholly made of a polymeric material. The first strobel layer 328 is secured to the second strobel layer 330 at the peripheral flange 320 to enclose the interior cavity 318. Stated differently, when the first strobel layer 328 and the second strobel layer 330 are secured together at the peripheral flange 320 and the strobel fluid-filled bladder 316 is sealed, the first strobel layer 328 and the second strobel layer 330 retain a fluid in the interior cavity 318. As used herein, the term “fluid” means a gas, such as air, nitrogen, another gas, or a combination thereof.

[0069] The first strobel layer 328 and the second strobel layer 330 can be made a variety of polymeric materials that can resiliently retain a fluid such as nitrogen, air, or another gas. Examples of polymeric materials for the first strobel layer 328 and the second strobel layer 330 include thermoplastic urethane, polyurethane, polyester, polyester polyurethane, and polyether polyurethane. Moreover, the first strobel layer 328 and the second strobel layer 330 can each be formed of layers of different materials including polymeric materials. In one embodiment, each of the first strobel layer 328 and the second strobel layer 330 is formed from thin films having one or more thermoplastic polyurethane layers with one or more barrier layers of a copolymer of ethylene and vinyl alcohol (EVOH) that is impermeable to the pressurized fluid contained therein such as a flexible microlayer membrane that includes alternating layers of a gas barrier material and an elastomeric material. Alternatively, the first strobel layer 328 and the second strobel layer 330 may include ethylene-vinyl alcohol copolymer, thermoplastic polyurethane, and a regrind material of the ethylene-vinyl alcohol copolymer and thermoplastic polyurethane. Further suitable materials for the first strobel layer 328 and the second strobel layer 330 include thermoplastic films containing a crystalline material, and polyurethane including a polyester polyol. In selecting materials for the strobel board 210, engineering properties such as tensile strength, stretch properties, fatigue characteristics, dynamic modulus, and loss tangent can be considered. For example, the thicknesses of the first strobel layer 328 and the second strobel layer 330 used to form the strobel board 210 can be selected to provide these characteristics.

[0070] As best shown in FIG. 11, a tensile component 350 is disposed in the strobel interior cavity 318. The tensile component 350 is secured to opposing inner surfaces 352, 354 of the strobel fluid-filled bladder 316. The tensile component 350 includes a first tensile layer 356, a second tensile layer 358, and a plurality of strobel tethers 360 spanning the strobel interior cavity 318 from the first tensile layer 356 to the second tensile layer 358. The strobel tethers 360 connect the first tensile layer 356 to the second tensile layer 358. Therefore, the tethers 360 interconnect the first strobel layer 328 and the second strobel layer 330. Only some of the strobel tethers 360 are indicated with reference numbers in FIG. 11. The strobel tethers 360 may also be referred to as fabric tensile members or threads and may be in the form of drop threads that connect the first tensile layer 356 and the second tensile layer 358. The tensile component 350 may be formed as a unitary, one-piece textile element having a spacer-knit textile.

[0071] The first tensile layer 356 is bonded to the inner surface 352 of the first strobel layer 328, and the second tensile layer 358 is bonded to the inner surface 354 of the second strobel layer 330. More specifically, a first surface bond 362 joins the inner surface 352 of the first strobel layer 328 to the outer surface 364 of the first tensile layer 356. A second surface bond 366 joins the inner surface 354 of the second strobel layer 330 to the outer surface 368 of the second tensile layer 358, opposite the first tensile layer 356. Entire interfacing portions of the surfaces 352, 364 and of the surfaces 354, 368 are bonded to one another.

[0072] The strobel tethers 360 restrain separation of the first strobel layer 328 and the second strobel layer 330 to the maximum separated positions shown in FIG. 11, which depicts the strobel fluid-filled bladder 316 with the strobel interior cavity 318 inflated and sealed under a given inflation pressure of gas in the interior cavity 318, so that the strobel fluid-filled bladder 316 is in an inflated state. The outward force on the first strobel layer 328 and the second strobel layer 330 due to the pressurized gas in the strobel interior cavity 318 places the strobel tethers 360 in tension, and the strobel tethers 360 prevent the first and second tensile layers 356, 358 and first strobel layer 328 and the second strobel layer 330 from further outward movement away from one another. However, the strobel tethers 360 do not present resistance to compression when under a compressive load. When pressure is exerted on the strobel fluid-filled bladder 316 such as due to compressive forces of a dynamic load of a wearer when the article of footwear 100 impacts the ground during running or other movements. Rather, upon exertion of compressive forces on the article of footwear 100, the strobel fluid-filled bladder 316 is compressed, and the first strobel layer 328 and the second strobel layer 330 move closer together as the strobel tethers 360 collapse (e.g., go slack) in proportion to the load on the first strobel layer 328 and the second strobel layer 330 adjacent the particular strobel tethers 360.

[0073] One or more inwardly-protruding bonds 370 joins the first strobel layer 328 to the first tensile layer 356 and protrudes inward from the first strobel layer 328 toward the second strobel layer 330 directly into a region of the strobel interior cavity 318 occupied by some of the strobel tethers 360. The plurality of inwardly-protruding bonds 370 protrude inward from the first strobel layer 328 only partially across the plurality of strobel tethers 360 toward the second strobel layer 330, and the strobel fluid-filled bladder 316 is narrowed at the inwardly-protruding bonds 370. For example, the inwardly-protruding bonds 370 may be formed by a welding process, such as radio frequency or ultrasonic welding using tooling that results in thermal bonds in the strobel fluid-filled bladder 316. The inwardly-protruding bonds 370 result in depressed grooves 374 at the proximal surface 324 of the first strobel layer 328.

[0074] Because the inwardly-protruding bonds 370 at least partially traverse the plurality of strobel tethers 360 and the plurality of strobel tethers 360 includes first strobel tethers 360A aligned with one of the inwardly-protruding bonds 370, the second strobel tethers 360B displaced each of the inwardly-protruding bonds 370. Only some of the first and second strobel tethers 360A, 360B are labelled in FIG. 11. The first strobel tethers 360A that are aligned with an inwardly-protruding bond 370 are deformed by heat, by compression of the overlaying of material of the first tensile layer 356, and/or by the overlaying material of the first tensile layer 356 coating the first strobel tethers 360A such that the first strobel tethers 360A are shorter, thicker, or both shorter and thicker at the inwardly-protruding bonds 370 than elsewhere. The first tensile layer 356 is spaced apart from the second tensile layer 358 by a first distance D1 at the second strobel tethers 360B adjacent to the inwardly-protruding bond 370, and the inwardly-protruding bond 370 is spaced apart from the second tensile layer 358 by a second distance D2, which may be the minimum distance between the inwardly-protruding bond 370 and the second tensile layer 358 (i.e., the distance at the most narrowed portion of the interior cavity 318 under the inwardly-protruding bond 370).

[0075] With reference to FIGS. 12 and 13, the present disclosure also describes a method 400 of manufacturing an outsole 214. The method 400 begins at block 402. At block 402, a molten polymeric material 410 is injected into a mold cavity 502 of a mold 500. The mold 500 includes a mold body 504 and a plurality of inserts 506 detachably coupled to the mold body 504. The mold body 504 defines the mold cavity 502. The mold cavity 502 is shaped as the outsole 214. The inserts 506 may be made of a metallic material and are shaped to form gaps 217 between the outsole plate 216 of the outsole 214 and each of the traction elements 218. After injecting the polymeric material 410, the method 400 proceeds to block 404. At block 404, the polymer material 410 is cooled until the polymeric material 410 solidifies. Then, the method 400 proceeds to block 406. At block 406, the inserts 506 are removed from polymeric material 410 after the polymeric material 410 solidifies to form the gaps 217. To remove the inserts 506, the inserts 506 may be handpicked from the polymeric material 410 after the polymeric material 410 solidifies. Alternately or additionally, removing the plurality of inserts may include applying a magnetic field toward the inserts 506 to withdraw the inserts 506 from the polymeric material 410 after the polymeric material 410 has solidified.

[0076] While various embodiments have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the embodiments. Any feature of any embodiment may be used in combination with or substituted for any other feature or element in any other embodiment unless specifically restricted. Accordingly, the embodiments are not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.

[0077] While several modes for carrying out the many aspects of the present teachings have been described in detail, those familiar with the art to which these teachings relate will recognize various alternative aspects for practicing the present teachings that are within the scope of the appended claims. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and exemplary of the entire range of alternative embodiments that an ordinarily skilled artisan would recognize as implied by, structurally and/or functionally equivalent to, or otherwise rendered obvious based upon the included content, and not as limited solely to those explicitly depicted and/or described embodiments.