Patent Description:
The present disclosure relates generally to sole structures for articles of footwear and more particularly to sole structures incorporating a fluid-filled bladder having a plurality of segments.

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.

Midsoles employing fluid-filled bladders typically include a bladder formed from two barrier layers of polymer material that are sealed or bonded together. The fluid-filled bladders are pressurized with a fluid such as air, and may incorporate tensile members within the bladder to retain the shape of the bladder when compressed resiliently under applied loads, such as during athletic movements. Generally, bladders are designed with an emphasis on balancing support for the foot and cushioning characteristics that relate to responsiveness as the bladder resiliently compresses under an applied load.

Document <CIT> describes a sole structure for an article of footwear comprises a midsole including a polymeric bladder element enclosing a fluid-filled interior cavity, a first outsole component secured to a bottom and a side surface of the polymeric bladder element, and a second outsole component. The first outsole component includes a first base, and a wall integral with the first base. The second outsole component includes a second base secured to the first base, and a wall integral with the second base and secured to the outer surface of the wall of the first outsole component. The first base has a first portion with integral tread elements. The second base is secured to a second portion of the first base free of tread elements.

The drawings described herein are for illustrative purposes only of selected configurations and are not intended to limit the scope of the present disclosure, which is defined by the appended claims.

Example configurations are provided so that this disclosure will be thorough, and will fully convey the scope of the disclosure as defined by the appended claims 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, as defined by the appended claims.

Referring to <FIG> and <FIG>, an article of footwear <NUM> includes an upper <NUM>, a midsole <NUM> attached to the upper <NUM>, and an outsole <NUM> extending between the midsole <NUM> and a ground surface. The article of footwear <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>. The forefoot region <NUM> may correspond with toes and joints connecting metatarsal bones with phalanx bones of a 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> may include lateral and medial sides <NUM>, <NUM>, respectively, corresponding with opposite sides of the footwear <NUM> and extending through the regions <NUM>, <NUM>, <NUM>.

The upper <NUM> includes interior surfaces that define an interior void <NUM> configured to receive and secure a foot for support on the midsole <NUM>. The upper <NUM> may be formed from one or more materials that are stitched or adhesively bonded together to form the interior void <NUM>. Suitable materials of the upper may include, but are not limited to, mesh, textiles, foam, leather, and synthetic leather. The materials may be selected and located to impart properties of durability, air-permeability, wear-resistance, flexibility, and comfort.

In some examples, the upper <NUM> includes a strobel <NUM> having a bottom surface <NUM> opposing the midsole <NUM> and an opposing top surface defining a footbed <NUM> of the interior void <NUM>. Stitching or adhesives may secure the strobel <NUM> to the upper <NUM>. As shown in <FIG>, the footbed <NUM> may be contoured to conform to a profile of the bottom surface (e.g., plantar) of the foot. Optionally, the upper <NUM> may also incorporate additional layers such as an insole <NUM> or sockliner that may be disposed upon the strobel <NUM> and reside within the interior void <NUM> of the upper <NUM> to receive a plantar surface of the foot to enhance the comfort of the article of footwear <NUM>. An ankle opening <NUM> in the heel region <NUM> may provide access to the interior void <NUM>. For example, the ankle opening <NUM> may receive a foot to secure the foot within the void <NUM> and facilitate entry and removal of the foot from and to the interior void <NUM>.

In some examples, one or more fasteners <NUM> extend along the upper <NUM> to adjust a fit of the interior void <NUM> around the foot and to accommodate entry and removal of the foot therefrom. The upper <NUM> may include apertures <NUM> such as eyelets and/or other engagement features such as fabric or mesh loops that receive the fasteners <NUM>. The fasteners <NUM> may include laces, straps, cords, hook-and-loop, or any other suitable type of fastener. The upper <NUM> may include a tongue portion <NUM> that extends between the interior void <NUM> and the fasteners <NUM>.

As illustrated in <FIG>, the midsole <NUM> includes a bladder <NUM> defined by an upper barrier layer <NUM> (hereinafter `upper layer <NUM>') and a lower barrier layer <NUM> (hereinafter 'lower layer <NUM>'). The upper layer <NUM> and the lower layer <NUM> define barrier layers for the bladder <NUM> by joining together and bonding at a plurality of discrete locations during a molding or thermoforming process to form a flange <NUM> extending around the periphery of the midsole <NUM> and a web area <NUM> extending between the lateral and medial sides <NUM> and <NUM> of the midsole <NUM>. The flange <NUM> and the web area <NUM> are disposed proximate to the upper <NUM> and, thus, are recessed relative to a ground-engaging surface <NUM> of the outsole <NUM>.

The upper layer <NUM> of the bladder <NUM> opposes and attaches (e.g., joins and bonds) to the bottom surface <NUM> of the strobel <NUM> of the upper <NUM>. Additionally, the upper layer <NUM> of the bladder <NUM> may be contoured to conform to a profile of the bottom surface of the foot to provide cushioning and support for the foot. The upper layer <NUM> may be formed from one or more polymer materials during a molding process or a thermoforming process and may include an outer peripheral edge that extends upward upon an outer periphery of the upper <NUM>. The lower layer <NUM> of the bladder <NUM> is disposed on an opposite side of the bladder <NUM> than the upper layer <NUM>. The lower layer <NUM> may include an outer peripheral edge that extends upward toward the upper <NUM> and bonds with the outer peripheral edge of the upper layer <NUM> to form the flange <NUM>. As with the upper layer <NUM>, the lower layer <NUM> may be formed from the same or a different material than the upper layer <NUM> during the molding or thermoforming process.

In some implementations, the upper and lower layers <NUM>, <NUM> are formed by respective mold portions each defining various surfaces for forming depressions and pinched surfaces corresponding to locations where the flange <NUM> and/or the web area <NUM> are formed when the lower layer <NUM> and the upper layer <NUM> join and bond together. In some implementations, adhesive bonding joins the upper layer <NUM> and the lower layer <NUM> to form the flange <NUM> and the web area <NUM>. In other implementations, the upper layer <NUM> and the lower layer <NUM> are joined to form the flange <NUM> and the web area <NUM> by thermal bonding. In some examples, one or both of the upper and lower layers <NUM>, <NUM> are heated to a temperature that facilitates shaping and melding. In some examples, the layers <NUM>, <NUM> are heated prior to being located between their respective molds. In other examples, the mold may be heated to raise the temperature of the layers <NUM>, <NUM>. In some implementations, a molding process used to form the bladder <NUM> incorporates vacuum ports within mold portions to remove air such that the upper and lower layers <NUM>, <NUM> are drawn into contact with respective mold portions. In other implementations, fluids such as air may be injected into areas between the upper and lower layers <NUM>, <NUM> such that pressure increases cause the layers <NUM>, <NUM> to engage with surfaces of their respective mold portions.

In some implementations, the midsole <NUM> may include a polymer foam layer (not shown) disposed between the upper layer <NUM> of the bladder <NUM> and the upper <NUM>. Thus, the optional foam layer of the midsole <NUM> is operative as an intermediate layer to indirectly attach the upper layer <NUM> of the bladder <NUM> to the upper <NUM> by joining the upper layer <NUM> of the bladder <NUM> to the upper <NUM> and/or to the bottom surface <NUM> of the strobel <NUM>. The optional foam layer may also join the lower layer <NUM> to the outsole <NUM>, thereby securing the midsole <NUM> and the outsole <NUM> to the upper <NUM>. Moreover, the foam layer of the footwear <NUM> may also reduce the extent to which the upper layer <NUM> extends onto the peripheral surfaces of the upper <NUM> and, therefore, increases durability of the footwear <NUM> by reducing the possibility of the upper layer <NUM> detaching from the upper <NUM> over extended use of the footwear <NUM>.

In some implementations, an overmold portion extends over a portion of the bladder <NUM> to provide increased durability and resiliency for the chambers <NUM>, <NUM>, <NUM> when under applied loads. The overmold portion may extend over the forefoot region <NUM>, the mid-foot region <NUM>, and/or the heel region <NUM> by attaching to the lower layer <NUM> to provide increased durability and resiliency for the bladder <NUM> where the separation distance between the lower layer <NUM> and the upper layer <NUM> are larger, or to provide increased thickness in specific areas of the bladder, such as the heel region <NUM>. In some examples, the overmold portion is bonded to the lower layer <NUM> and includes at least one of a different thickness, a different hardness, and a different material than the lower layer <NUM>. The overmold portion may limited to only areas of the lower layer <NUM> that partially define the segments residing in the heel and mid-foot regions <NUM> and <NUM> and, therefore, the overmold portion may be absent from the flange <NUM> and web area <NUM>.

In some examples, the outsole <NUM> includes the ground-engaging surface <NUM> and an opposite inner surface <NUM> that attaches to regions of the lower layer <NUM> that define the chambers <NUM>, <NUM>, <NUM>. Accordingly, the outsole <NUM> may include a plurality of segments each defining a shape that conforms to the shape of a respective chambers <NUM>, <NUM>, <NUM>, whereby the outsole <NUM> is absent in regions between the chambers <NUM>, <NUM>, <NUM> to thereby expose the flange <NUM> and web area <NUM> of the bladder <NUM>. The outsole <NUM> generally provides abrasion-resistance and traction with the ground surface and may be formed from one or more materials that impart durability and wear-resistance, as well as enhance traction with the ground surface. For example, rubber may form at least a portion of the outsole <NUM>.

The ground-engaging surface <NUM> of the outsole <NUM> may be defined by a plurality of contact pads <NUM>. In some examples, the contact pads <NUM> extend from the lower layer <NUM> of the bladder <NUM> in a direction away from the upper <NUM> to provide increased traction with the ground surface. The contact pads <NUM> may have a corresponding shape to the ground-engaging surface <NUM> of the outsole <NUM>. For example, one of the contact pads <NUM> may be formed on each of the reservoirs <NUM>, <NUM>, <NUM> and may have an oval or obround shape corresponding to the prolate hemispheroidal shape of one or more of the reservoirs <NUM>, <NUM>, <NUM>. The contact pads <NUM> may also cause the bottom surface of the foot to reside higher above the ground surface. With reference to <FIG>, the contact pads <NUM> may include recesses or voids <NUM> to impart properties of improved traction and responsiveness.

In the illustrated example, the outsole <NUM> is formed as the overmold portion, as described above. Accordingly, the outsole <NUM> may be formed integrally with the lower layer <NUM> of the bladder <NUM> using an overmolding process. In other examples the outsole <NUM> may be formed separately from the lower layer <NUM> of the bladder <NUM> and adhesively bonded to the lower layer <NUM>.

Referring to <FIG>, the bladder <NUM> includes one or more chambers <NUM>, <NUM>, <NUM>. In the illustrated example, a first chamber <NUM> extends from the mid-foot region <NUM> to a toe portion of the forefoot region <NUM>, a second chamber <NUM> extends through the heel region <NUM>, and a third chamber <NUM> is disposed within the mid-foot region between the first chamber <NUM> and the second chamber <NUM>.

In the illustrated example, the first chamber <NUM> is fluidly coupled to the second chamber <NUM> indirectly via the third chamber <NUM>. Additionally or alternatively, the first chamber <NUM> may be directly fluidly coupled to the second chamber <NUM>.

In some implementations, the lower layer <NUM> defines a geometry (e.g., thicknesses, width, and lengths) of the plurality of chambers <NUM>, <NUM>, <NUM>. The lower layer <NUM> and the upper layer <NUM> may join and bond together in a plurality of discrete areas between the lateral side <NUM> and the medial side <NUM> of the bladder <NUM> to form portions of the web area <NUM> that bound and separate the chambers <NUM>, <NUM>, <NUM>. Thus, each chamber <NUM>, <NUM>, <NUM> is associated with an area of the bladder <NUM> where the upper and lower layers <NUM>, <NUM> are not joined together and, thus, are separated from one another to form respective voids.

The flange <NUM> and the web area <NUM> may cooperate to bound and extend around each of the chambers <NUM>, <NUM>, <NUM> to contain the fluid (e.g., air) within the bladder <NUM>. In some examples, regions of the web area <NUM> are bounded entirely by the chambers <NUM>, <NUM>, <NUM>, and define flexion zones to facilitate flexing of the footwear <NUM> as the midsole <NUM> rolls along the ground surface. As shown in <FIG>, no portion of the web area <NUM> extends continuously between the lateral side <NUM> and the medial side <NUM>.

With reference to <FIG>, each chamber <NUM>, <NUM>, <NUM> may define a substantially tubular cross-sectional shape and a thickness that extends substantially perpendicular to the longitudinal axis L of the midsole <NUM> between the upper layer <NUM> and the lower layer <NUM>. As such, the thickness of each chamber <NUM>, <NUM>, <NUM> is defined by a distance the lower layer <NUM> protrudes away from the upper layer <NUM> in a direction away from the upper <NUM>. At least two of the segments 218a-<NUM> of the first and second chambers <NUM>, <NUM> may define different thicknesses. For example, the segments 218e-<NUM> disposed in the heel region <NUM> may be associated with greater thicknesses than thicknesses associated one or more of segments 218a-218d disposed in the forefoot region <NUM>. Further, the thickness within any of the segments 218a-218e may be variable, such that a first portion of one of the segments 218a-218e has a different thickness from a second portion of the one of the segments 218a-218e. As shown in <FIG>, a thickness of the midsole <NUM> gradually decreases from the heel region <NUM> to the forefoot region <NUM> to provide a greater degree of cushioning for absorbing ground-reaction forces of greater magnitude that initially occur in the heel region <NUM> and lessen as the forefoot region <NUM> of the midsole <NUM> rolls for engagement with the ground surface. In some examples, the third chamber <NUM> is disposed in the mid-foot region <NUM> and is associated with a lesser thickness than the first chamber <NUM> and the second chamber <NUM>, such that the lower layer <NUM> is recessed from the ground-engaging surface <NUM> of the outsole <NUM>.

Each of the chambers <NUM>, <NUM>, <NUM> may be filled with a pressurized fluid (i.e., gas, liquid) to provide cushioning and stability for the foot during use of the footwear <NUM>. In some implementations, compressibility of a first portion of the chambers <NUM>, <NUM>, <NUM> under an applied load provides a responsive-type cushioning, while a second portion of the chambers <NUM>, <NUM>, <NUM> may be configured to provide a soft-type cushioning under an applied load. Accordingly, the chambers <NUM>, <NUM>, <NUM> of the bladder <NUM> may cooperate to provide gradient cushioning to the article of footwear <NUM> that changes as the applied load changes (i.e., the greater the load, the more the chambers <NUM>, <NUM>, <NUM> are compressed and, thus, the more responsive the footwear <NUM> performs).

In other implementations, one or more cushioning materials, such as polymer foam and/or particulate matter (none shown), are enclosed by one or more of the chambers <NUM>, <NUM>, <NUM> in place of, or in addition to, the pressurized fluid to provide cushioning for the foot. In these implementations, the cushioning materials may provide portions of one or more of the chambers <NUM>, <NUM>, <NUM> with cushioning properties different from portions of the chambers <NUM>, <NUM>, <NUM> filled with the pressurized fluid. For example, the cushioning materials may be more or less responsive or provide greater impact absorption than the pressurized fluid.

With reference to <FIG>, the geometry and configuration of the chambers <NUM>, <NUM>, <NUM> is shown with reference to a bottom perspective view of the footwear <NUM>. As described above, the chambers <NUM>, <NUM>, <NUM> are formed in areas of the midsole <NUM> where the upper layer <NUM> and the lower layer <NUM> are separated and spaced apart from one another to define respective voids for enclosing the pressurized fluid or cushioning material. As such, the flange <NUM> and the web area <NUM> correspond to areas of the bladder <NUM> where the upper layer <NUM> and the lower layer <NUM> are joined and bonded, and cooperate to bound and define a perimeter of each chamber <NUM>, <NUM>, <NUM> to thereby seal the pressurized fluid therein.

In some implementations, the chambers <NUM>, <NUM>, <NUM> are in fluid communication with one another to form a unitary pressure system for the bladder <NUM>. The unitary pressure system directs the fluid through the chambers <NUM>, <NUM>, <NUM> when under an applied load as the chambers <NUM>, <NUM>, <NUM> compress or expand to provide cushioning, as well as stability and support, by attenuating ground-reaction forces especially during forward running movements of the footwear <NUM>. Optionally, a portion of one or more of the chambers <NUM>, <NUM>, <NUM> may be fluidly isolated from the other chambers <NUM>, <NUM>, <NUM> so that at least one of the segments 218a-<NUM> can be pressurized differently.

In some examples, the first chamber <NUM> includes a plurality of segments 218a-218d spaced from the forefoot region <NUM> to the mid-foot region of the midsole <NUM>, and extending from the lateral side <NUM> to the medial side <NUM>. As shown, the segments 218a-218d of the first chamber <NUM> define U-shaped ribs extending continuously from the lateral side <NUM> of the midsole <NUM> to the medial side <NUM> of the midsole <NUM>. In one example, the first chamber <NUM> includes three segments 218a-218c spaced from the forefoot region <NUM> to the mid-foot region <NUM> and a fourth segment 218d extending continuously around the toe portion of the forefoot region <NUM>. Each of the segments 218a-218c includes a plurality of discretely formed reservoirs <NUM>, <NUM>, <NUM> connected with each other by conduits <NUM>, <NUM>, as described below.

Each of the segments 218a-218c includes a lateral reservoir 220a-220c disposed adjacent the lateral side <NUM> of the midsole <NUM>, a central reservoir 222a-222c disposed between the lateral side <NUM> and the medial side <NUM>, and a medial reservoir <NUM>-224c disposed adjacent the medial side <NUM> of the midsole <NUM>. The lateral reservoirs 220a-220c of each of the segments 218a-218c define prolate hemispheroids having a major axis 30a<NUM>-30c<NUM> extending in a direction along the lateral side <NUM> of the midsole <NUM>. Likewise, the medial reservoirs 224a-224c of each of the segmented segments 218a-218c may also define prolate hemispheroids having major axes 30a<NUM>-30c<NUM> extending in a direction along the medial side <NUM> of the midsole <NUM>. The central reservoir 222a-222c of each segment 218a-218c defines a prolate hemispheroid having a major axis 30a<NUM>-30c<NUM> extending transverse to each of the lateral side <NUM> and the medial side <NUM>. More particularly, the major axis of each of the central reservoirs 222a-222c is substantially perpendicular to the longitudinal axis L of the footwear <NUM>.

The first chamber <NUM> further includes the fourth segment 218d extending around a toe portion of the forefoot region <NUM>, from a first end on the lateral side <NUM> to a second end on the medial side <NUM>. In one example, the fourth segment 218d is a continuously-formed, fluid-filled segment. In other examples, the fourth segment 218d may include distinct reservoirs similar to the segments 218a-218c of the first chamber <NUM>.

Referring still to <FIG>, the first chamber <NUM> includes a plurality of conduits <NUM>, <NUM>, <NUM>, <NUM> fluidly coupling the reservoirs <NUM>, <NUM>, <NUM>. Each of the segments 218a-218c includes a respective lateral conduit 226a-226c fluidly coupling the lateral reservoir 220a-220c to the central reservoir 222a-222c, and a respective medial conduit 228a-228c fluidly coupling the medial reservoir 224a-224c to the central reservoir 222a-222c.

In addition to the reservoirs <NUM>, <NUM>, <NUM> of each one of the respective segments 218a-218c being fluidly coupled to each other, the adjacent ones of the segments 218a-218d are fluidly coupled to each other along the lateral side <NUM> and the medial side <NUM> by a plurality of longitudinal conduits 230a-230f. For example, the lateral end of the segment 218d is coupled to the first lateral reservoir 220a of the first segment 218a by a first longitudinal conduit 230a and the medial end of the segment 218d is coupled to the first medial reservoir 224a by a second longitudinal conduit 232a. Similarly, the first lateral reservoir 220a is fluidly coupled to the second lateral reservoir 220b by a third longitudinal conduit 230b and the first medial reservoir 224a is fluidly coupled to the second medial reservoir 224b by a fourth longitudinal conduit 232b. Further, the second lateral reservoir 220b is fluidly coupled to the third lateral reservoir by a fifth longitudinal conduit 230c, and the second medial reservoir 224b is coupled to the third medial reservoir 224c by a sixth longitudinal conduit 232c. The longitudinal conduits extend in a direction substantially along the lateral and medial sides <NUM>, <NUM> of the midsole <NUM>. Additionally or alternatively, adjacent ones of the central reservoirs 222a-222c of each of the segments 218a-218c may be fluidly coupled to each other by conduits (not shown). In some examples, two or more of the lateral conduits <NUM> and/or the longitudinal conduits <NUM> of adjacent ones of the segments 218a-218c may be fluidly coupled to each other by sub-conduits (not shown).

In some examples, the segments 218a-218c and the reservoirs <NUM>, <NUM>, <NUM> are in fluid communication with one another to form a unitary pressure system for the first chamber <NUM>. The unitary pressure system directs the fluid through the reservoirs <NUM>, <NUM>, <NUM> and conduits <NUM>, <NUM>, <NUM>, <NUM> when under an applied load as the reservoirs <NUM>, <NUM>, <NUM> compress or expand to provide cushioning, as well as stability and support, by attenuating ground-reaction forces especially during forward running movements of the footwear <NUM>. Optionally, one or more of the reservoirs <NUM>, <NUM>, <NUM> may be fluidly isolated from the other reservoirs <NUM>, <NUM>, <NUM> so that at least one of the segments 218a-218d or reservoirs <NUM>, <NUM>, <NUM> can be pressurized differently.

As shown in <FIG>, the central reservoirs 222a-222c of each one of the segments 218a-218c are disposed closer to the toe of the footwear <NUM> than the respective lateral and medial reservoirs 220a-220c, 224a-220c of each segment 218a-218c. For example, the major axis 30a<NUM>-30c<NUM> of each of the central reservoirs 222a-222c is disposed forward of a minor axis 32ai-32ci, 32a<NUM>-32c<NUM> of the respective lateral and medial reservoirs 220a-220c, 224a-220c. As such, each of the segments 218a-218c defines a horseshoe shape, opening towards the heel region <NUM> of the midsole <NUM>. Further, the central reservoir 222b of the second segment 218b may be partially disposed between the lateral reservoir 220a and the medial reservoir 224a of the first segment 218a, while the central reservoir 222c of the third segment 218c is partially disposed between the lateral reservoir 220b and the medial reservoir 224b of the second segment 218b.

In some configurations, the second chamber <NUM> includes a series of connected segments 218e-<NUM> surrounding the heel region <NUM> of the midsole <NUM>. A fifth segment 218e extends along the lateral side <NUM> of the midsole <NUM> within the heel region <NUM>, a sixth segment 218f extends along the medial side <NUM> of the midsole <NUM> within the heel region <NUM>, and a seventh segment <NUM> extends around the heel region <NUM> and fluidly couples to the fifth and sixth segments 218e, 218f. Thus, the second chamber <NUM> may generally define a horse-shoe shape, wherein the seventh segment <NUM> couples to the fifth and sixth segments 218e, 218f at respective ones of the lateral side <NUM> and the medial side <NUM>. In some examples, the sixth segment 218f includes a length greater than a length of the fifth segment 218e. For instance, the seventh segment <NUM> may extend farther along the lateral side towards the mid-foot region <NUM> than along the medial side <NUM>. Accordingly, the sixth segment 218f may extend a greater distance along the medial side <NUM> of the heel region <NUM> of the midsole <NUM> than the fifth segment extends along the lateral side <NUM>.

Each of the segments 218e-<NUM> may be filled with a pressurized fluid to impart cushioning characteristics. However, as introduced above, at least one of the segments 218e-<NUM> of the second chamber <NUM> may include one or more cushioning materials in place of, or in addition to, a pressurized fluid to provide cushioning and responsiveness different from the pressurized fluid of the other segments 218e-<NUM>. For example, the seventh segment <NUM> may include the cushioning material in place of the fluid-filled chamber, such that the seventh segment <NUM> is configured to absorb an initial impact of the ground-reaction force.

As shown in <FIG>, the third chamber <NUM> includes a fluid-filled reservoir disposed in the mid-foot region <NUM> of the sole structure, between the lateral side <NUM> and the medial side <NUM>. In some examples, the third chamber <NUM> defines a prolate hemispheroid having a major axis <NUM> extending substantially along the longitudinal axis L of the midsole <NUM>. A toe-facing end of the third chamber <NUM> is disposed between the lateral reservoir 220c and the medial reservoir 224c of the third segment 218c, and a heel-facing end of the third chamber <NUM> may be disposed between the fifth segment 218e and the sixth segment 218f of the second chamber <NUM>.

The third chamber <NUM> is fluidly coupled to the first chamber <NUM> by a first pair of conduits <NUM>. For example, a first conduit <NUM> fluidly couples the third chamber <NUM> directly to the third lateral reservoir 220c of the first chamber <NUM> and a second conduit <NUM> fluidly couples the third chamber <NUM> directly to the third medial reservoir 224c of the first chamber. Similarly, third and fourth conduits <NUM> fluidly couple the third chamber <NUM> directly to each of the fifth segment 218e and the sixth segment 218f of the second chamber <NUM>.

<FIG> provides a cross-sectional view taken along line <NUM>-<NUM> of <FIG> showing the midsole <NUM> in the forefoot region <NUM> with the insole <NUM>, the strobel <NUM> of the upper <NUM>, and the upper layer <NUM> of the bladder <NUM> arranged in the layered configuration as described above with reference to <FIG> and <FIG>. The peripheral edges of the lower layer <NUM> may extend upward toward the upper <NUM> and join with the peripheral edges of the upper layer <NUM> to form the flange <NUM> along the medial side <NUM> and the lateral side <NUM>. The lower layer <NUM> of the bladder <NUM> may also extend toward the upper <NUM> and join with the upper layer <NUM> to form a region of the web area <NUM> that extends between and separates the reservoirs 220a, 224a. For instance, the lateral reservoir 220a is bounded by the web area <NUM> and the flange <NUM> formed at the lateral side <NUM>, while the medial reservoir 224a is bounded by the web area <NUM> and the flange <NUM> formed at the medial side <NUM>.

The outsole <NUM> attaches to and conforms in shape with each of the reservoirs 220a, 224a. In some examples, the contact pad <NUM> extends from the outsole <NUM> in a direction away from the upper <NUM> and along respective lengths of the reservoirs 220a, 224a to provide increased traction with the ground surface.

<FIG> provides a cross-sectional view taken along line <NUM>-<NUM> of <FIG> showing the midsole <NUM> in the forefoot region <NUM> with the insole <NUM>, the strobel <NUM> of the upper <NUM>, and the upper layer <NUM> of the bladder <NUM> arranged in the layered configuration as described above with reference to <FIG> and <FIG>. The peripheral edges of the lower layer <NUM> may extend upward toward the upper <NUM> and join with the peripheral edges of the upper layer <NUM> to form the flange <NUM> along the medial side <NUM> and the lateral side <NUM>. As shown, the lower layer <NUM> is spaced apart from the upper layer <NUM> from the lateral side <NUM> to the medial side <NUM>. For instance, the lower layer <NUM> defines the lateral reservoir 220b, the lateral conduit 226b, the central reservoir 222b, the medial conduit 228b, and the medial reservoir 224b formed successively across the midsole <NUM> from the lateral side <NUM> to the medial side <NUM>.

The outsole <NUM> attaches to and conforms in shape with each of the reservoirs 220b, 222b, 224b. In some examples, the contact pad <NUM> extends from the outsole <NUM> in a direction away from the upper <NUM> and along respective lengths of the reservoirs 220a, 224a to provide increased traction with the ground surface.

<FIG> provides a cross-sectional view taken along line <NUM>-<NUM> of <FIG> showing the midsole <NUM> in the heel region <NUM> with the insole <NUM>, the strobel <NUM> of the upper <NUM>, and the upper layer <NUM> of the bladder <NUM> arranged in the layered configuration as described above with reference to <FIG> and <FIG>. The peripheral edges of the lower layer <NUM> may extend upward toward the upper <NUM> and join with the peripheral edges of the upper layer <NUM> to form the flange <NUM> along the lateral side <NUM> and the medial side <NUM>. Relative to the view of <FIG>, the lower layer <NUM> protrudes away from the upper layer <NUM> in a direction away from the upper <NUM> to define the segments 218e, 218f that extend along respective ones of the lateral side <NUM> and the medial side <NUM>.

In some implementations, the fifth segment 218e extending along the lateral side <NUM> and the sixth segment 218f extending along the medial side <NUM> each include semi-tubular cross-sectional shapes relative to the view of <FIG> to facilitate inward and/or outward rolling of the midsole <NUM> during lateral movements. Each of the segments 218e, 218f may further include a necked region <NUM> formed intermediate adjacent contact pads <NUM> and having a reduced thickness to allow the segments 218e, 218f to absorb the initial impact of a ground-reaction force and thereby compress before the ground-reaction force is applied to the necked region <NUM>. As such a trampoline effect is created as the fluid-filled segments 218e, 218f compress in succession, thereby providing gradient responsive-type cushioning as the outsole <NUM> rolls for engagement with the ground surface.

<FIG> provides a cross-sectional view taken along line <NUM>-<NUM> of <FIG> showing the upper <NUM>, the midsole <NUM>, and the outsole <NUM> extending through forefoot region <NUM>, the mid-foot region <NUM>, and the heel region <NUM>. As described above with reference to the footwear <NUM> of <FIG> and <FIG>, the outsole <NUM> attaches to portions of the lower layer <NUM> in regions where the chambers <NUM>, <NUM> protrude away from the upper <NUM> to provide increased durability and resiliency for the bladder <NUM> in the heel region <NUM>, the mid-foot region <NUM>, and the forefoot region <NUM>. Moreover, the segments 218a-218d, <NUM> extend between the lateral side <NUM> and the medial side <NUM>. The web area <NUM> may separate and extend between the segments 218a-218d, <NUM> relative to the view of <FIG>. In some examples, the segments 218a-218d extend into the forefoot region <NUM> and are associated with a smaller thickness than segments 218e-<NUM> in the heel region <NUM> and/or mid-foot region <NUM>.

<FIG> provides a bottom perspective view of the segments 218a, 218b, 218d fluidly connected to one another and disposed within the forefoot region <NUM> of the midsole <NUM>. In some examples, the outsole <NUM> includes a shape that conforms to the shape and contour of the segments 218a, 218b, 218d (as well as segments 218c and 218e-g) and attaches to the segments 218a-<NUM> via melding and/or adhesive.

<FIG> provides a bottom perspective view of the article of footwear <NUM> of <FIG> showing a plurality of cushioning support vectors <NUM> defined by the segments 218a-<NUM>. More particularly, a longitudinal axis <NUM> of each of the segments 218a-<NUM> define respective ones of the cushioning support vectors 30a-<NUM>. Applied loads associated with directions parallel to a cushioning support vector cause the one or more corresponding segments to substantially retain their shape without collapsing to provide support and stability for the foot in those regions. On the other hand, applied loads associated with directions transverse to a cushioning support vector cause the one or more corresponding segments to compress and collapse to provide cushioning for the foot in those regions by attenuating the ground-reaction force associated with the applied load. The longitudinal cushioning support vectors 30a<NUM>-30c<NUM>, 30a<NUM>-30c<NUM>, 30e, 30f may extend along the longitudinal axis L of the midsole <NUM> while the lateral cushioning support vectors 30a<NUM>-30c<NUM>, 30d extend transversely to the longitudinal axis L of the midsole <NUM>. For instance, the lateral cushioning support vectors 30a<NUM>-30c<NUM>, 30d may define angles within <NUM> degrees (<NUM>°) from perpendicular relative to the longitudinal axis L of the midsole <NUM>. The seventh segment <NUM> defines a pair of compound cushioning support vectors 30gi, <NUM><NUM>, whereby the curved segment <NUM> provides responsive support along both the longitudinal and lateral directions of the midsole <NUM>.

During forward movements, such as walking or running movements, loads applied to the midsole <NUM> are associated with a direction parallel to the longitudinal cushioning support vectors 30a<NUM>-30c<NUM>, 30a<NUM>-30c<NUM>, 30e, 30f to cause the respective reservoirs 220a-220c, 224a-224c and segments 218e, 218f to be under shear force, thereby causing the respective reservoirs 220a-220c, 224a-224c and segments 218e, 218f to retain their shape (e.g., not compress) and provide support and stability as the outsole rolls for engagement with the ground surface through the heel region <NUM> and the mid-foot region <NUM>. The web area <NUM> extending between the reservoirs 220a-220c, 224a-224c and segments 218e, 218f reduces torsional forces from acting upon the reservoirs 220a-220c, 224a-224c and segments 218e, 218f when under applied load to thereby dampen oscillations by the foot while providing gradient responsive-type cushioning.

During lateral movements, such as shifting or cutting movements, loads applied to the midsole <NUM> are associated with a direction transverse and generally perpendicular to longitudinal cushioning support vectors 30a<NUM>-30c<NUM>, 30a<NUM>-30c<NUM>, 30e, 30f. Thus, the reservoirs 224a-224c and segment 218f defining the vectors 30a<NUM>-30c<NUM>, 30f will compress to provide cushioning for the medial side of the foot when the applied load is in a direction toward the medial side <NUM> of the midsole <NUM>, while the reservoirs 220a-220c and segment 218e defining the vectors 30a<NUM>-30c<NUM>, 30e will compress to provide cushioning for the lateral side of the foot when the applied load is in a direction toward the lateral side <NUM> of the midsole <NUM>.

In some implementations, a series of the lateral cushioning support vectors 30a<NUM>-30c<NUM>, 30d are disposed within the mid-foot <NUM> and forefoot region <NUM> and extend substantially parallel to one another in a direction transverse to the longitudinal axis L of the midsole <NUM>. During forward movements, such as walking or running movements, loads applied to the midsole <NUM> are associated with a direction transverse to the lateral cushioning support vectors 30a<NUM>-30c<NUM>, 30d. Thus, the respective reservoirs 222a-222c and segment 218d defining respective ones of the vectors 30a<NUM>-30c<NUM>, 30d successively compress and collapse to provide cushioning for the metatarsal region of the foot through push off from the ground-surface. The direction of the vectors 30a<NUM>-30c<NUM>, 30d relative to the direction of the applied load as well as a length of the respective reservoirs 222a-222c and segment 218d dictates how the segments will compress for attenuating the ground-reaction force.

During lateral movements, such as shifting or cutting movements, loads applied to the midsole <NUM> are associated with a direction generally parallel or only slightly transverse to the lateral cushioning support vectors 30a<NUM>-30c<NUM>, 30d to cause the respective reservoirs 222a-222c and segment 218d to be under shear force, thereby causing the respective reservoirs 222a-222c and segment 218d to retain the their shape (e.g., not compress or slightly compress) and provide support and stability for the metatarsal region of the foot responsive to the footwear <NUM> performing a lateral movement.

As provided above, the seventh segment <NUM> further defines a pair of compound cushioning support vector 30gi, <NUM><NUM> which are each configure to provide a degree of both longitudinal cushioning and responsiveness and lateral cushioning and responsiveness, thereby supplementing the lateral cushioning support vectors 30a<NUM>-30c<NUM>, 30d and the longitudinal cushioning support vectors 30a<NUM>-30c<NUM>, 30a<NUM>-30c<NUM>, 30e, 30f.

The segments 218a-<NUM> associated with the chambers <NUM>, <NUM>, <NUM> may cooperate to enhance the functionality and cushioning characteristics that a conventional midsole provides, while simultaneously providing increased stability and support for the foot by dampening oscillations of the foot that occur in response to a ground-reaction force during use of the footwear <NUM>. For instance, an applied load to the midsole <NUM> during forward movements, such as walking or running movements, may cause some of the segments 218a-<NUM> to compress to provide cushioning for the foot by attenuating the ground-reaction force, while other segments 218a-<NUM> may retain their shape to impart stability and support characteristics that dampen foot oscillations relative to the footwear <NUM> responsive to the initial impact of the ground-reaction force.

Moreover, one or more of the segments 218a-<NUM> may interact with the web area <NUM> within different regions <NUM>, <NUM>, <NUM> of the midsole <NUM> to provide isolated areas of responsive-type cushioning. For example, the segments 218e-<NUM> within the heel region <NUM> may bound a respective portion of the web area <NUM> to provide responsive-type cushioning in the heel region <NUM> by causing the segments 218e-<NUM> around the perimeter of the heel region <NUM> to absorb the initial impact of a ground-reaction force by creating a trampoline effect as portions of the segments 218e-<NUM> compress in succession, and thereby provide a gradient responsive-type cushioning in the heel region <NUM>.

Claim 1:
A sole structure for an article of footwear (<NUM>) having an upper (<NUM>), the sole structure including a midsole (<NUM>) attachable to the upper (<NUM>) and an outsole (<NUM>) extending between the midsole (<NUM>) and a ground surface, the sole structure comprising:
a heel region (<NUM>);
a forefoot region (<NUM>) including a toe portion;
a mid-foot region (<NUM>) disposed between the heel region (<NUM>) and the forefoot region (<NUM>); the midsole (<NUM>) including:
a first chamber (<NUM>) extending from the mid-foot region (<NUM>) to the toe portion of the forefoot region (<NUM>) and including a plurality of segments (218a-218d) that extend from a lateral side (<NUM>) to a medial side (<NUM>) of the midsole (<NUM>), wherein the plurality of segments (218a-218d) comprises:
(i) a first segment (218a) having a medial reservoir (224a) defining a prolate hemispheroid shape including a major axis (<NUM>) extending along the medial side (<NUM>) of the midsole (<NUM>), a lateral reservoir (220a) defining a prolate hemispheroid shape including a major axis (<NUM>) extending along the lateral side (<NUM>) of the midsole (<NUM>) and a central reservoir (222a) defining a prolate hemispheroid having a major axis (<NUM>) extending transverse to each of the medial side (<NUM>) and the lateral side (<NUM>) of the midsole (<NUM>); and
(ii) a second segment (218b) having a lateral reservoir (220b) defining a prolate hemispheroid shape including a major axis (<NUM>) extending along the lateral side (<NUM>) of the midsole (<NUM>), a medial reservoir (224b) defining a prolate hemispheroid shape including a major axis (<NUM>) extending along the medial side (<NUM>) of the midsole (<NUM>) and a central reservoir (222b) defining a prolate hemispheroid having a major axis (<NUM>) extending transverse to each of the medial side (<NUM>) and the lateral side (<NUM>) of the midsole (<NUM>).