Patent Description:
Sole structures generally 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 enhance 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 may be 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 additionally or alternatively incorporate a fluid-filled bladder to increase durability of the sole structure, as well as to provide cushioning to the foot by compressing resiliently under an applied load to attenuate ground-reaction forces. Sole structures may also include a comfort-enhancing insole or a sockliner located within a void proximate to the bottom portion of the upper and a strobel attached to the upper and disposed between the midsole and the insole or sockliner.

<CIT> describes a sole for health footwear having a barefoot technology.

<CIT> describes a sole for shoes and a process for producing said sole.

The subject matter of the claimed invention is defined in the independent claim. Specific embodiments are defined in the dependent claims.

One aspect of the disclosure provides a sole structure for an article of footwear. The sole structure includes an interior cushioning arrangement extending from an anterior end to a posterior end. The sole structure also includes a forefoot cushioning element extending from the anterior end to a first end and including a first material having a first durometer. The sole structure further includes a heel cushioning element extending from the posterior end to a second end and including a second material having a second durometer, the first end of the forefoot cushioning element and the second end of the heel cushioning element overlapping one another. The interior cushioning arrangement includes a first surface having a first portion formed by the forefoot cushioning element and a second portion formed by the heel cushioning element. A plate is disposed adjacent to the first surface of the interior cushioning arrangement. The plate extends from a first end at an anterior end of the sole structure to a second end at a posterior end of the sole structure. The second durometer is less than the first durometer. The plate is formed of one or more rigid or semi-rigid materials having a greater durometer than any of the cushioning elements.

Implementations of the disclosure may include one or more of the following optional features. The plate may be disposed within a socket formed in the first surface of the interior cushioning arrangement. Optionally, an upper cushioning element may be disposed on an opposite side of the plate than the interior cushioning arrangement and may include a third material having a third durometer. Here, the third durometer may be greater than the first durometer and the second durometer.

In some examples, the sole structure includes an outer shell formed of a fourth material and defining a receptacle, the interior cushioning arrangement at least partially received within the receptacle. The first material may be a first foamed elastomer and the second material may be a second foamed elastomer. The first end may include a first beveled surface and the second end may have a second beveled surface, the first beveled surface mating with the second beveled surface.

Referring to <FIG>, an article of footwear <NUM> includes a sole structure <NUM> and an upper <NUM> attached to the sole structure <NUM>. The article of footwear <NUM>, the sole structure <NUM>, and the upper <NUM> may be divided into one or more regions. The regions may include a forefoot region <NUM>, a mid-foot region <NUM>, and a heel region <NUM>. As indicated in <FIG>, the forefoot region <NUM> may be described as including a toe portion <NUM>T corresponding with the phalanges of the foot, and a ball portion <NUM>B corresponding to the metatarsophalangeal (MTP) joint of the foot. The mid-foot region <NUM> may correspond with an arch area of the foot, and the heel region <NUM> may correspond with rear portions of the foot, including a calcaneus bone. The footwear <NUM>, the sole structure <NUM>, and the upper <NUM> may further include an anterior end <NUM> associated with a forward-most point of the forefoot region <NUM>, and a posterior end <NUM> corresponding to a rearward-most point of the heel region <NUM>. A longitudinal axis A<NUM> of the footwear <NUM> extends along a length of the footwear <NUM> from the anterior end <NUM> to the posterior end <NUM>, and generally divides the footwear <NUM> into a medial side <NUM> and a lateral side <NUM>, as shown in <FIG>. Accordingly, the medial side <NUM> and the lateral side <NUM> respectively correspond with opposite sides of the footwear <NUM> and extend through the regions <NUM>, <NUM>, <NUM>.

With reference to <FIG>, the sole structure <NUM> includes a midsole <NUM> configured to provide cushioning and performance characteristics to the sole structure <NUM>, and an outsole <NUM> configured to provide a ground-engaging surface of the article of footwear <NUM>. Unlike conventional sole structures, the midsole <NUM> of the sole structure <NUM> may be formed compositely and include a plurality of subcomponents for providing desired forms of cushioning and support throughout the sole structure <NUM>. For example, the midsole <NUM> includes an interior cushioning arrangement <NUM> having a forefoot cushioning element <NUM> and a heel cushioning element <NUM>, an upper cushioning element <NUM> disposed on a top side of the interior cushioning arrangement <NUM>, and a plate <NUM> disposed between the interior cushioning arrangement <NUM> and the upper cushioning element <NUM>. Similarly, the outsole <NUM> includes an outer shell <NUM> configured to receive a portion of the midsole <NUM> therein, and a heel counter <NUM> disposed at the posterior end <NUM>.

With reference to <FIG>, the interior cushioning arrangement <NUM> is itself formed as a composite structure including the forefoot cushioning element <NUM> and the heel cushioning element <NUM>. In the illustrated example, opposing ends (i.e., facing each other) of the forefoot cushioning element <NUM> and the heel cushioning element <NUM> interface with each other along a central joint <NUM> (<FIG>) to form a substantially continuous body including the forefoot cushioning element <NUM> and the heel cushioning element <NUM>. The forefoot cushioning element <NUM> is formed of a different material than the heel cushioning element <NUM> to provide the interior cushioning arrangement <NUM> with different cushioning properties in the different regions <NUM>, <NUM>, <NUM>. The heel cushioning element <NUM> is formed of a material having a lower durometer than the forefoot cushioning element <NUM> to provide the heel region <NUM> with a softer feel than the forefoot region <NUM>. Accordingly, the heel cushioning element <NUM> will provide greater impact attenuation than the forefoot cushioning element <NUM>.

The interior cushioning arrangement <NUM> includes a top surface <NUM> formed on a first side, a bottom surface <NUM> formed on an opposite side than the top surface <NUM>, and a peripheral side surface <NUM> extending between the top surface <NUM> and the bottom surface <NUM>. A distance from the top surface <NUM> to the bottom surface <NUM> defines a thickness of the interior cushioning arrangement <NUM>. As shown, when the interior cushioning arrangement <NUM> is assembled, the forefoot cushioning element <NUM> and the heel cushioning element <NUM> cooperate with each other to define each of the top surface <NUM>, the bottom surface <NUM>, and the peripheral side surface <NUM>. In other words, the forefoot cushioning element <NUM> includes respective first portions of each of the top surface <NUM>, the bottom surface <NUM>, and the peripheral side surface <NUM>, and the heel cushioning element <NUM> includes respective second portions of each of the top surface <NUM>, the bottom surface <NUM>, and the peripheral side surface <NUM>. Accordingly, features of the entire interior cushioning arrangement <NUM> or either of the forefoot cushioning element <NUM> or the heel cushioning element <NUM> may be described in terms of one or more of the surfaces <NUM>, <NUM>, <NUM>.

Referring again to <FIG>, the forefoot cushioning element <NUM> extends along the longitudinal axis A<NUM> from a first distal end <NUM> facing the anterior end <NUM> of the article of footwear <NUM>, to a first proximal end <NUM> facing the posterior end <NUM> of the article of footwear <NUM>. The heel cushioning element <NUM> extends along the longitudinal axis A<NUM> from a second distal end <NUM> facing the posterior end <NUM> of the article of footwear <NUM>, to a second proximal end <NUM> facing the anterior end <NUM> of the article of footwear <NUM>. Accordingly, when the interior cushioning arrangement <NUM> is assembled, the distal ends <NUM>, <NUM> of the respective cushioning elements <NUM>, <NUM> form opposite terminal ends <NUM>, <NUM> of the interior cushioning arrangement <NUM>, while the proximal ends <NUM>, <NUM> cooperate to form the central joint <NUM> of the interior cushioning arrangement <NUM>.

As best shown in <FIG>, the first proximal end <NUM> and the second proximal end <NUM> include complementary or cooperating engagement surfaces <NUM>, <NUM>, which are configured to interface with each other to form a substantially uninterrupted interior cushioning arrangement <NUM>. Here, each of the proximal ends <NUM>, <NUM> includes a respective beveled engagement surface <NUM>, <NUM> extending between the top surface <NUM> and the bottom surface <NUM> of the interior cushioning arrangement <NUM>, such that at least a portion of one of the engagement surfaces <NUM>, <NUM> overlaps with at least a portion of the other one of the engagement surfaces <NUM>, <NUM>. In some examples, each of the engagement surfaces <NUM>, <NUM> is formed as a bevel extending continuously and completely from the top surface <NUM> to the bottom surface <NUM>, such that the entire first engagement surface <NUM> of the forefoot cushioning element <NUM> overlaps or is overlapped by the entire second engagement surface <NUM> of the heel cushioning element <NUM>. For example, as shown in <FIG>, the first engagement surface <NUM> extends rearward (i.e., toward the posterior end <NUM>) from the bottom surface <NUM> at a first angle θ<NUM> such that the thickness of the forefoot cushioning element <NUM> tapers towards the top surface <NUM> and the first proximal end <NUM>. Conversely, as shown in <FIG>, the second proximal end <NUM> extends forward from the top surface <NUM> at a second angle θ<NUM> such that the thickness of the heel cushioning element <NUM> tapers towards the bottom surface <NUM> and the second proximal end <NUM>.

With reference to <FIG>, the engagement surfaces <NUM>, <NUM> of each of the cushioning elements <NUM>, <NUM> include respective engagement features <NUM>, <NUM> configured to interface with each other to provide the central joint <NUM> with increased integrity. Generally, first engagement features <NUM> of the forefoot cushioning element <NUM> are configured to interface or mate with corresponding second engagement features <NUM> of the heel cushioning element <NUM> to secure a relative position of the forefoot cushioning element <NUM> and the heel cushioning element <NUM>. In the illustrated example, the engagement features <NUM>, <NUM> of each of the engagement surfaces <NUM>, <NUM> include respective pluralities of steps <NUM>, <NUM> arranged in series from the top surface <NUM> to the bottom surface <NUM>. Here, the steps <NUM> of the first engagement surface <NUM> are configured to mate with the steps <NUM> of the second engagement surface <NUM>. As shown, the steps <NUM>, <NUM> may be formed as undulations, whereby edges of the steps <NUM>, <NUM> are radiused to form complementary concave and convex surfaces extending across a width of the interior cushioning arrangement <NUM>. In one configuration, the convex portions of the first engagement surface <NUM> may be matingly received by the concave portions of the second engagement surface <NUM>, and the concave portions of the first engagement surface <NUM> may matingly receive the convex portions of the second engagement surface <NUM> (<FIG>). In so doing, a good connection between the surfaces <NUM>, <NUM> is achieved by (i) creating a mating connection between the surfaces <NUM>, <NUM> and (ii) increasing the contact area between the surfaces <NUM>, <NUM> (as compared to flat, opposing surfaces). Additionally or alternatively, the proximal end <NUM>, <NUM> of one or both of the cushioning elements <NUM>, <NUM> may be formed with lateral engagement features <NUM> (e.g., projections, undulations) for interfacing with the other of the cushioning elements <NUM>, <NUM>.

Providing the beveled central joint <NUM> with the stepped or undulated engagement surfaces <NUM>, <NUM> provides a secure transitional region along a central portion of the interior cushioning arrangement <NUM>. Particularly, the beveled configuration provides a gradual transition from the first durometer of the forefoot cushioning element <NUM> to the second durometer of the heel cushioning element <NUM>, which provides a desired underfoot feel. The stepped interface between the cushioning elements <NUM>, <NUM> functions to secure a relative longitudinal position between the cushioning elements <NUM>, <NUM>, whereby the first proximal end <NUM> of the forefoot cushioning element <NUM> is prevented from creeping or sliding longitudinally along the second proximal end <NUM> of the heel cushioning element <NUM>. Further providing one or both of the proximal ends <NUM>, <NUM> with lateral engagement features <NUM> secures a relative lateral position between the forefoot cushioning element <NUM> and the heel cushioning element <NUM>.

With continued reference to <FIG>, the top surface <NUM> of the interior cushioning arrangement <NUM> includes a socket <NUM> configured for receiving at least a portion of the plate <NUM> therein when the sole structure <NUM> is assembled. In the illustrated example, a depth of the socket <NUM> corresponds to a thickness of the plate <NUM>, such that when the sole structure <NUM> is assembled, a top surface of the plate <NUM> is flush with the top surface <NUM> of the interior cushioning arrangement <NUM>. As shown, the socket <NUM> may extend continuously across a width of the interior cushioning arrangement <NUM> to intersect with the peripheral side surface <NUM> on the medial side <NUM> and the lateral side <NUM> in the forefoot region <NUM> and the heel region <NUM>. Accordingly, when the sole structure <NUM> is assembled, an outer periphery of the plate <NUM> may be exposed through the peripheral side surface <NUM> on the medial side <NUM> and the lateral side <NUM>.

Referring to <FIG>, <FIG>, and <FIG>, the interior cushioning arrangement <NUM> may include a flange <NUM> extending around the second distal end <NUM> of the heel cushioning element <NUM>, from the medial side <NUM> to the lateral side <NUM>. The flange <NUM> includes a planar, downward-facing surface <NUM> configured to rest upon a corresponding step <NUM> formed within the outsole <NUM>, as discussed in greater detail below. As shown in <FIG> and <FIG>, a height H<NUM> of the flange <NUM>, measured as a distance from the bottom surface <NUM> to the downward-facing surface <NUM>, gradually increases along each of the medial and lateral sides <NUM>, <NUM> to a maximum height at the second distal end <NUM>.

The upper cushioning element <NUM> extends longitudinally from a first end <NUM> at the anterior end <NUM> to a second end <NUM> at the posterior end <NUM>. The upper cushioning element <NUM> includes a top surface <NUM> configured to form a footbed of the sole structure <NUM>, a bottom surface <NUM> formed on an opposite side of the upper cushioning element <NUM> than the top surface <NUM>, and a peripheral side surface <NUM> extending from the top surface <NUM> to the bottom surface <NUM> and defining an outer periphery of the upper cushioning element <NUM>. A distance from the top surface <NUM> to the bottom surface <NUM> defines a thickness T<NUM> of the upper cushioning element <NUM>.

The cushioning elements <NUM> are formed of a resilient polymeric material, such as foam or rubber, to impart properties of cushioning, responsiveness, and energy distribution to the foot of the wearer. In the illustrated example, the forefoot cushioning element <NUM> is formed of a first foam material, the heel cushioning element <NUM> is formed of a second foam material, and the upper cushioning element <NUM> is formed of a third foam material. For example, the forefoot cushioning element <NUM> may be formed of a first foamed material having a first durometer, the heel cushioning element <NUM> may be formed of a second foamed material having a second durometer that is less than the first durometer, and the upper cushioning element <NUM> may be formed of a third material having a third durometer that is higher than the first durometer and the second durometer. The cushioning elements <NUM>, <NUM>, <NUM> may be affixed to each other using a fusing process, using an adhesive, or by suspending the elements in a different resilient polymeric material. Alternatively, the plurality of elements may not be affixed to each other, but may remain independent. As discussed above, the cushioning elements <NUM>, <NUM>, <NUM> may be formed with cooperating geometries (e.g., steps, protrusions) for restricting relative motion between the cushioning elements <NUM>, <NUM>, <NUM>.

Example resilient polymeric materials for the cushioning elements <NUM>, <NUM>, <NUM> may include those based on foaming or molding one or more polymers, such as one or more elastomers (e.g., thermoplastic elastomers (TPE)). The one or more polymers may include aliphatic polymers, aromatic polymers, or mixtures of both; and may include homopolymers, copolymers (including terpolymers), or mixtures of both.

In further aspects, the one or more polymers may include one or more polyamide copolymers (e.g., polyamide-polyether copolymers) and/or one or more polyurethanes (e.g., crosslinked polyurethanes and/or thermoplastic polyurethanes). Alternatively, the one or more polymers may include one or more natural and/or synthetic rubbers, such as butadiene and isoprene.

When the resilient polymeric material is a foamed polymeric material, the foamed material may be foamed using a physical blowing agent which phase transitions to a gas based on a change in temperature and/or pressure, or a chemical blowing agent which forms a gas when heated above its activation temperature. For example, the chemical blowing agent may be an azo compound such as adodicarbonamide, sodium bicarbonate, and/or an isocyanate.

With continued reference to <FIG>, the plate <NUM> extends from a first end <NUM> at the anterior end <NUM> of the sole structure <NUM> to a second end <NUM> at the posterior end <NUM> of the sole structure <NUM>. The plate <NUM> includes a top surface <NUM>, a bottom surface <NUM> formed on an opposite side of the plate <NUM> than the top surface <NUM>, and a peripheral side surface <NUM> extending from the top surface <NUM> to the bottom surface <NUM> and defining a peripheral profile of the plate <NUM>. A distance from the top surface <NUM> to the bottom surface <NUM> defines a thickness T<NUM> of the plate <NUM>. In the illustrated example, the thickness T<NUM> of the plate <NUM> is substantially constant. The plate <NUM> is formed of one or more rigid or semi-rigid materials having a greater durometer than any of the cushioning elements <NUM>, <NUM>, <NUM>. In some examples, the plate <NUM> is formed of an elastomeric material, such as a nylon. Additionally or alternatively, the plate <NUM> may include one or more composite materials.

As shown in <FIG>, when the sole structure <NUM> is assembled, the plate <NUM> is disposed within the socket <NUM> of the interior cushioning arrangement <NUM> and is interposed between the interior cushioning arrangement <NUM> and the upper cushioning element <NUM>. As shown, the thickness T<NUM> of the plate <NUM> is the same as a depth D<NUM> of the socket <NUM>, such that the top surface <NUM> of the plate <NUM> is flush with the top surface <NUM> of the interior cushioning arrangement <NUM> when the sole structure is assembled. Accordingly, when the sole structure is assembled, the top surface <NUM> of the plate <NUM> and the top surface <NUM> of the interior cushioning arrangement <NUM> form a continuous surface upon which the bottom surface <NUM> of the upper cushioning element <NUM> rests.

With reference to <FIG>, the plate <NUM> may include a necked portion <NUM> extending through the mid-foot region <NUM>. The necked portion <NUM> is a portion of the plate <NUM> in the mid-foot region <NUM> having a reduced width W<NUM> relative to the adjacent portions of the plate <NUM> in the forefoot region <NUM> and the heel region <NUM>. As shown in <FIG>, the necked portion <NUM> is formed where a portion of the peripheral side surface <NUM> along the medial side <NUM> is inwardly offset towards the interior of the plate <NUM> (i.e., the longitudinal axis A<NUM>) and forms a recess <NUM> along the medial side <NUM> of the plate <NUM>. A longitudinal position of the necked portion <NUM> corresponds to the position of lateral arch of the foot, while a longitudinal position of the recess <NUM> corresponds to the position of the medial arch of the foot. In other words, the plate <NUM> is absent in a portion of the sole structure <NUM> corresponding to the medial arch of the foot. This configuration allows the plate <NUM> to provide support to the plantar surface of the foot along the lateral side <NUM>, while maximizing flexibility of the sole structure through the mid-foot region <NUM>.

With continued reference to <FIG>, the plate <NUM> includes a compound curvature extending from the first end <NUM> to the second end <NUM>, and may be described as including different portions 172a-172d each having a different curvature. Particularly, the plate <NUM> includes a toe portion 172a, a ball portion 172b, a mid-foot portion 172c, and a heel portion 172d, which are respectively disposed in the corresponding regions <NUM>T, <NUM>B, <NUM>, <NUM>. As shown, the toe portion 172a extends from the first end <NUM> of the plate <NUM> and is substantially straight. Each of the ball portion 172b and the heel portion 172d form concave portions of plate <NUM> where the top surface <NUM> has a concave curvature. The mid-foot portion 172c forms a portion of the plate <NUM> where the top surface <NUM> has a convex curvature. Accordingly, the top surface <NUM> of the plate <NUM> is cupped in the forefoot region <NUM> and the heel region <NUM>, and forms an inverted (i.e., convex) transition region between the ball portion 172b and the heel portion 172d.

Referring still to <FIG>, the ball portion 172b of the plate <NUM> is configured to support the metatarsophalangeal (MTP) joint of the foot. As shown, the ball portion 172b forms a concave potion of the top surface <NUM> having a radius R172b of curvature between the toe portion 172a and the mid-foot portion 172c. The ball portion 172b further includes a lower vertex <NUM> located at the lowermost point of the ball portion 172b. As shown in <FIG>, the lower vertex <NUM> is positioned approximately <NUM>% of the length L<NUM> of the plate from the second end <NUM> of the plate <NUM>.

As provided above, each of the mid-foot portion 172c and the heel portion 172d are also curved to accommodate curvature of the plantar surface of the foot. For example, the mid-foot portion 172c of the plate <NUM> curves along a second radius of curvature R172c that is less than the first radius of curvature R172b of the ball portion 172b, and forms a convex portion of the top surface <NUM>. The heel portion 172d of the plate <NUM> curves along a third radius curvature R172d that is less than the first radius of curvature R172b of the ball portion 172b, and forms a concave portion of the top surface <NUM>.

With continued reference to <FIG>, when the sole structure <NUM> is assembled, the midsole <NUM> has an overall thickness T<NUM> formed by the stacking of the interior cushioning arrangement <NUM> (e.g., T<NUM>, T<NUM>), the upper cushioning element <NUM> (e.g., T<NUM>), and the plate <NUM> (e.g., T<NUM>). The overall thickness T<NUM> is variable along the length of the midsole <NUM>, whereby the thickness T<NUM> increases through the forefoot region <NUM> to the mid-foot region <NUM>, and then decreases from the mid-foot region <NUM> to the heel region <NUM>. Here, a thickness of the interior cushioning arrangement <NUM> is substantially constant beneath the plate <NUM> from the anterior end <NUM> to the lower vertex <NUM>, and then increases from the lower vertex <NUM> through the mid-foot region <NUM>. Conversely, the upper cushioning element <NUM> increases in thickness T<NUM> from the anterior end <NUM> to the lower vertex <NUM>, and then decreases through the mid-foot region to a substantially constant thickness T<NUM> in the heel region <NUM>. As shown, this configuration results in the upper cushioning element <NUM> being thicker than the interior cushioning arrangement <NUM> in the forefoot region <NUM>, and the interior cushioning arrangement <NUM> being thicker than the upper cushioning element <NUM> in the heel region <NUM>. In other words, the plate <NUM> is located closer to the ground surface than to the plantar surface of the foot in the forefoot region <NUM>, and is located closer to the plantar surface of the foot than to the ground surface in the heel region <NUM>.

As provided above, the outsole <NUM> may be constructed as a composite structure including the outer shell <NUM> and the heel counter <NUM>. Generally, the outer shell <NUM> is configured to form the ground-engaging surface of the article of footwear <NUM>, and is formed of one or more materials for imparting properties of cushioning, traction, and abrasion resistance. The heel counter <NUM> extends around the posterior end <NUM> of the article of footwear <NUM>, and is configured to provide stability around the heel region <NUM>. Accordingly, the heel counter <NUM> may be formed of a material having a greater hardness than the outer shell <NUM>. As best shown in <FIG> and <FIG>, when the outsole <NUM> is assembled, the outer shell <NUM> and the heel counter <NUM> cooperate to define a cavity <NUM> for receiving the midsole <NUM>.

Referring to <FIG>, the outer shell <NUM> of the outsole <NUM> extends from a first end <NUM> at the anterior end <NUM> of the article of footwear <NUM> to a second end <NUM> at the posterior end of the article of footwear <NUM>. Accordingly, the outer shell <NUM> extends along the full length of the article of footwear <NUM>. The outer shell <NUM> includes a ground-engaging element <NUM> extending continuously from the first end <NUM> to the second end <NUM>, and a peripheral wall <NUM> extending from the ground-engaging element <NUM> along a perimeter of the outer shell <NUM>.

As shown in <FIG> and <FIG>, the ground-engaging element <NUM> includes a top surface <NUM> and a bottom surface <NUM> formed on an opposite side of the ground-engaging element <NUM> than the top surface <NUM>. Here, the bottom surface <NUM> of the ground-engaging element <NUM> forms a ground-engaging surface <NUM> of the article of footwear <NUM>. A distance from the top surface <NUM> to the bottom surface <NUM> defines a thickness of the ground-engaging element <NUM>.

The peripheral wall <NUM> extends substantially perpendicularly from the top surface <NUM> of the ground-engaging element <NUM> and bounds a first portion of the cavity <NUM> of the outsole <NUM>. As shown, the peripheral wall <NUM> includes a first portion 184a extending around the first end <NUM> of the outer shell <NUM> and a second portion 184b extending around the second end <NUM> of the outer shell <NUM>. As indicated in <FIG>, the first portion 184a of the peripheral wall <NUM> has a first height H184a and the second portion 184b of the peripheral wall <NUM> has a second height H184b. The first height H184a is greater than the second height H184b such that the first portion 184a protrudes beyond (i.e., above) the second portion 184b and includes a pair of terminal ends 190a, 190b configured to interface with the heel counter <NUM>. In the illustrated example, the terminal ends 190a, 190b may be offset from each other, such that the terminal end 190a on the medial side <NUM> is closer to the anterior end <NUM> than the terminal end 190b on the lateral side <NUM>. Accordingly, the first portion 184a of the peripheral wall <NUM> extends farther along the lateral side <NUM> than the medial side <NUM>.

As shown in <FIG> and <FIG>, the outer shell <NUM> may include a channel <NUM> formed at least partially through a thickness of the outer shell <NUM>. In the illustrated example, a length of the channel <NUM> extends from a first terminal end 193a on the medial side <NUM> of the ground-engaging element <NUM> to a second terminal end 193b in the peripheral wall on the lateral side <NUM> of the ground-engaging element <NUM>. In the ground-engaging element <NUM>, the channel <NUM> is formed across a width (i.e., transverse to the longitudinal axis A<NUM>) of the bottom surface <NUM> in the ball portion <NUM>B and has an S-shaped curvature from the medial side <NUM> to the lateral side <NUM>.

As discussed above, the outer shell <NUM> may further include a step <NUM> formed at the second end <NUM>. The step <NUM> is configured to support the flange <NUM> formed at the second distal end <NUM> of the heel cushioning element <NUM>. Accordingly, the step <NUM> may include a substantially planar, upward-facing surface extending around the second end <NUM>. Here, a height of the step <NUM> increases along each of the medial and lateral sides <NUM>, <NUM> to a maximum height at the second end <NUM>.

In the illustrated example, the outer shell <NUM> is formed as a unitary body of a single elastomeric material, such as a natural or synthetic rubber material. The material of the outer shell <NUM> is selected to provide characteristics of cushioning, traction, and abrasion resistance to the outsole <NUM>. In some examples, the ground-engaging element <NUM> and the peripheral wall <NUM> may be formed of different materials and then attached to each other.

The heel counter <NUM> is configured to interface with the peripheral wall <NUM> of the outer shell <NUM>. As shown, the heel counter <NUM> is a U-shaped element that extends from a first terminal end 196a on the medial side <NUM> to a second terminal end 196b on the lateral side <NUM>. Each of the first terminal end 196a and the second terminal end 196b are configured to interface with respective terminal ends 190a, 190b of the first portion 184a of the peripheral wall <NUM>. For example, a profile of each of the terminal ends 196a, 196b of the heel counter <NUM> corresponds to profile of a respective one of the terminal ends 190a, 190b of the peripheral wall <NUM>, such that when the heel counter <NUM> is assembled with the outer shell <NUM>, the peripheral wall <NUM> and the heel counter <NUM> cooperate to continuously bound the cavity <NUM> of the outsole <NUM>.

Claim 1:
A sole structure (<NUM>) for an article of footwear (<NUM>), the sole structure (<NUM>) comprising:
an interior cushioning arrangement (<NUM>) extending from an anterior end to a posterior end and including (i) a forefoot cushioning element (<NUM>) extending from the anterior end to a first end (<NUM>) and including a first material having a first durometer, and (ii) a heel cushioning element (<NUM>) extending from the posterior end to a second end (<NUM>) and including a second material having a second durometer, the first end (<NUM>) of the forefoot cushioning element (<NUM>) and the second end (<NUM>) of the heel cushioning element (<NUM>) overlapping one another, and the interior cushioning arrangement (<NUM>) including a first surface (<NUM>) having a first portion formed by the forefoot cushioning element (<NUM>) and a second portion formed by the heel cushioning element (<NUM>); and
the sole structure (<NUM>) further comprising a plate (<NUM>) disposed adjacent to the first surface (<NUM>) of the interior cushioning arrangement (<NUM>), the plate (<NUM>) extending from a first end (<NUM>) at an anterior end (<NUM>) of the sole structure (<NUM>) to a second end (<NUM>) at a posterior end (<NUM>) of the sole structure (<NUM>);
wherein the second durometer is less than the first durometer and
the plate (<NUM>) is formed of one or more rigid or semi-rigid materials having a greater durometer than any of the cushioning elements.