Patent Description:
Articles of footwear generally include two primary elements: an upper and a sole structure. The upper may be formed from a variety of materials that are stitched or adhesively bonded together to form a void within the footwear for comfortably and securely receiving a foot. The sole structure is secured to a lower portion of the upper and is generally positioned between the foot and the ground. In many articles of footwear, including athletic footwear styles, the sole structure often incorporates an insole, a midsole, and an outsole.

In US Design Patent <CIT> an ornamental design for a shoe outsole is described. Document <CIT> discloses an article of footwear with an outsole in two parts.

The present invention is specified by the appended independent claim. Specific embodiments of the claimed invention result from the dependent claims.

Other features and advantages of the embodiments will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description.

<FIG> is an isometric view of an embodiment of an article of footwear <NUM>. In the exemplary embodiment, article of footwear <NUM> has the form of an athletic shoe. However, in other embodiments, the provisions discussed herein for article of footwear <NUM> could be incorporated into various other kinds of footwear including, but not limited to: basketball shoes, hiking boots, soccer shoes, football shoes, sneakers, running shoes, cross-training shoes, rugby shoes, baseball shoes as well as other kinds of shoes. Moreover, in some embodiments, the provisions discussed herein for article of footwear <NUM> could be incorporated into various other kinds of non-sports related footwear, including, but not limited to: slippers, sandals, high heeled footwear, and loafers.

For purposes of clarity, the following detailed description discusses the features of article of footwear <NUM>, also referred to simply as article <NUM>. However, it will be understood that other embodiments may incorporate a corresponding article of footwear (e.g., a right article of footwear when article <NUM> is a left article of footwear) that may share some, and possibly all, of the features of article <NUM> described herein and shown in the figures.

The embodiments may be characterized by various directional adjectives and reference portions. These directions and reference portions may facilitate in describing the portions of an article of footwear. Moreover, these directions and reference portions may also be used in describing sub-components of an article of footwear (e.g., directions and/or portions of an inner sole component, a midsole component, an outer sole component, an upper or any other components).

For consistency and convenience, directional adjectives are employed throughout this detailed description corresponding to the illustrated embodiments. The term "longitudinal" as used throughout this detailed description and in the claims refers to a direction extending a length of a component (e.g., an upper or sole component). In some cases, the longitudinal direction may extend from a forefoot portion to a heel portion of the component. Also, the term "lateral" as used throughout this detailed description and in the claims refers to a direction extending along a width of a component. In other words, the lateral direction may extend between a medial side and a lateral side of a component. Furthermore, the term "vertical" as used throughout this detailed description and in the claims refers to a direction generally perpendicular to a lateral and longitudinal direction. For example, in cases where an article is planted flat on a ground surface, the vertical direction may extend from the ground surface upward. Additionally, the term "inner" refers to a portion of an article disposed closer to an interior of an article, or closer to a foot when the article is worn. Likewise, the term "outer" refers to a portion of an article disposed further from the interior of the article or from the foot. Thus, for example, the inner surface of a component is disposed closer to an interior of the article than the outer surface of the component. This detailed description makes use of these directional adjectives in describing an article and various components of the article, including an upper, a midsole structure and/or an outer sole structure.

Article <NUM> may be characterized by a number of different regions or portions. For example, article <NUM> could include a forefoot portion, a midfoot portion, a heel portion and an ankle portion. Moreover, components of article <NUM> could likewise comprise corresponding portions. Referring to <FIG>, article <NUM> may be divided into forefoot portion <NUM>, midfoot portion <NUM> and heel portion <NUM>. Forefoot portion <NUM> may be generally associated with the toes and joints connecting the metatarsals with the phalanges. Midfoot portion <NUM> may be generally associated with the arch of a foot. Likewise, heel portion <NUM> may be generally associated with the heel of a foot, including the calcaneus bone. Article <NUM> may also include an ankle portion <NUM> (which may also be referred to as a cuff portion). In addition, article <NUM> may include lateral side <NUM> and medial side <NUM>. In particular, lateral side <NUM> and medial side <NUM> may be opposing sides of article <NUM>, Furthermore, both lateral side <NUM> and medial side <NUM> may extend through forefoot portion <NUM>, midfoot portion <NUM>, heel portion <NUM> and ankle portion <NUM>.

<FIG> illustrates an exploded isometric view of an embodiment of article of footwear <NUM>. <FIG> illustrate various components of article of footwear <NUM>, including an upper <NUM> and a sole structure <NUM>.

Generally, upper <NUM> may be any type of upper. In particular, upper <NUM> may have any design, shape, size and/or color. For example, in embodiments where article <NUM> is a basketball shoe, upper <NUM> could be a high top upper that is shaped to provide high support on an ankle. In embodiments where article <NUM> is a running shoe, upper <NUM> could be a low top upper.

In some embodiments, upper <NUM> includes opening <NUM> that provides entry for the foot into an interior cavity of upper <NUM>. In some embodiments, upper <NUM> may also include a tongue (not shown) that provides cushioning and support across the instep of the foot. Some embodiments may include fastening provisions, including, but not limited to: laces, cables, straps, buttons, zippers as well as any other provisions known in the art for fastening articles. In some embodiments, a lace <NUM> may be applied at a fastening region of upper <NUM>.

Some embodiments may include uppers that extend beneath the foot, thereby providing <NUM> degree coverage at some regions of the foot. However, other embodiments need not include uppers that extend beneath the foot. In other embodiments, for example, an upper could have a lower periphery joined with a sole structure and/or sock liner.

An upper could be formed from a variety of different manufacturing techniques resulting in various kinds of upper structures. For example, in some embodiments, an upper could have a braided construction, a knitted (e.g., warp-knitted) construction or some other woven construction. In an exemplary embodiment, upper <NUM> may be a knitted upper.

In some embodiments, sole structure <NUM> may be configured to provide traction for article <NUM>. In addition to providing traction, sole structure <NUM> may attenuate ground reaction forces when compressed between the foot and the ground during walking, running or other ambulatory activities. The configuration of sole structure <NUM> may vary significantly in different embodiments to include a variety of conventional or non-conventional structures. In some cases, the configuration of sole structure <NUM> can be configured according to one or more types of ground surfaces on which sole structure <NUM> may be used. Examples of ground surfaces include, but are not limited to: natural turf, synthetic turf, dirt, hardwood flooring, as well as other surfaces.

Sole structure <NUM> is secured to upper <NUM> and extends between the foot and the ground when article <NUM> is worn. In different embodiments, sole structure <NUM> may include different components. In the exemplary embodiment shown in <FIG>, sole structure <NUM> may include inner sole component <NUM>, midsole component <NUM> and a plurality of outer sole members <NUM>. In some cases, one or more of these components may be optional.

Referring now to <FIG>, in some embodiments, inner sole component <NUM> may be configured as an inner layer for a midsole. For example, as discussed in further detail below, inner sole component <NUM> may be integrated, or received, into a portion of midsole component <NUM>. However, in other embodiments, inner sole component <NUM> could function as an insole layer and/or as a strobel layer. Thus, in at least some embodiments, inner sole component <NUM> could be joined (e.g., stitched or glued) to lower portion <NUM> of upper <NUM> for purposes of securing sole structure <NUM> to upper <NUM>.

Inner sole component <NUM> may have an inner surface <NUM> and an outer surface <NUM>. Inner surface <NUM> may generally be oriented towards upper <NUM>. Outer surface <NUM> may be generally oriented towards midsole component <NUM>. Furthermore, a peripheral sidewall surface <NUM> may extend between inner surface <NUM> and outer surface <NUM>.

Midsole component <NUM> may be configured to provide cushioning, shock absorption, energy return, support, as well as possibly other provisions. To this end, midsole component <NUM> may have a geometry that provides structure and support for article <NUM>. Specifically, midsole component <NUM> may be seen to have a lower portion <NUM> and a sidewall portion <NUM>. Sidewall portion <NUM> may extend around the entire periphery <NUM> of midsole component <NUM>. As seen in <FIG>, sidewall portion <NUM> may partially wrap up the sides of article <NUM> to provide increased support along the base of the foot.

Midsole component <NUM> further includes an inner surface <NUM> and an outer surface <NUM>. Inner surface <NUM> may be generally oriented towards upper <NUM>, while outer surface <NUM> may be oriented outwardly. Furthermore, in the exemplary embodiment, midsole component <NUM> includes a central recess <NUM> disposed in inner surface <NUM>. Central recess <NUM> may generally be sized and configured to receive inner sole component <NUM>.

In some embodiments, midsole component <NUM> may include a plurality of holes <NUM>, at least some of which may extend through the entire thickness of midsole component <NUM>. In the exemplary embodiment shown in <FIG>, some of the plurality of holes <NUM> are visible within central recess <NUM>.

In different embodiments, midsole component <NUM> may generally incorporate various provisions associated with midsoles. For example, in one embodiment, a midsole component may be formed from a polymer foam material that attenuates ground reaction forces (i.e., provides cushioning) during walking, running, and other ambulatory activities. In various embodiments, midsole components may also include fluid-filled chambers, plates, moderators, or other elements that further attenuate forces, enhance stability, or influence the motions of the foot, for example.

<FIG> illustrates a bottom view of sole structure <NUM>. As seen in <FIG>, plurality of outer sole members <NUM> comprises four distinct outer sole members. Specifically, sole structure <NUM> includes a first outer sole member <NUM>, a second outer sole member <NUM>, a third outer sole member <NUM> and a fourth outer sole member <NUM>. Although the exemplary embodiment includes four different outer sole members, other embodiments could include any other number of outer sole members. In another embodiment, for example, only a single outer sole member may be present. In still another embodiment, only two outer sole members may be used. In still another embodiment, only three outer sole members could be used. In still other embodiments, five or more outer sole members could be used.

Generally, an outer sole member may be configured as a ground contacting member. In some embodiments, an outer sole member could include properties associated with outsoles, such as durability, wear-resistance and increased traction. In other embodiments, an outer sole member could include properties associated with a midsole, including cushioning, strength and support. In the exemplary embodiment, plurality of outer sole members <NUM> may be configured as outsole-like members that enhance traction with a ground surface while maintaining wear resistance.

In different embodiments, the locations of one or more outer sole members could vary. In some embodiments, one or more outer sole members could be disposed in a forefoot portion of a sole structure. In other embodiments, one or more outer sole members could be disposed in a midfoot portion of a sole structure. In still other embodiments, one or more outer sole members could be disposed in a heel portion of a sole structure. In an exemplary embodiment, first outer sole member <NUM> and second outer sole member <NUM> may be disposed in forefoot portion <NUM> of sole structure <NUM>. More specifically, first outer sole member <NUM> may be disposed on medial side <NUM> of forefoot portion <NUM>, while second outer sole member <NUM> may be disposed on lateral side <NUM> of forefoot portion <NUM>. In addition, in the exemplary embodiment third outer sole member <NUM> and fourth outer sole member <NUM> may be disposed in heel portion <NUM> of sole structure <NUM>. More specifically, third outer sole member <NUM> may be disposed on lateral side <NUM> and fourth outer sole member <NUM> may be disposed on medial side <NUM>. Furthermore, it can be seen that first outer sole member <NUM> and second outer sole member <NUM> are spaced apart from one another in the center of forefoot portion <NUM>, while third outer sole member <NUM> and fourth outer sole member <NUM> are spaced apart from one another in the center of heel portion <NUM>. This exemplary configuration provides outer sole members at areas of increased ground contact during various lateral and medial cuts, so as to enhance traction during these motions.

The sizes of various outer sole members could vary. In the exemplary embodiment, first outer sole member <NUM> may be the largest outer sole member of plurality of outer sole members <NUM>. Moreover, second outer sole member <NUM> may be substantially smaller than first outer sole member <NUM> thereby enhancing traction more on a medial side <NUM> of sole structure <NUM> than on lateral side <NUM> in forefoot portion <NUM>. At heel portion <NUM>, third outer sole member <NUM> and fourth outer sole member <NUM> are both widest along a rearward edge <NUM> of sole structure <NUM>, and taper slightly towards midfoot portion <NUM>.

Referring to <FIG> and <FIG>, first outer sole member <NUM> comprises an inner surface <NUM> and an outer surface <NUM>. Inner surface <NUM> may generally be disposed against midsole component <NUM>. Outer surface <NUM> may face outwardly and may be a ground contacting surface. For purposes of clarity, only the inner and outer surfaces of first outer sole member <NUM> are indicated in <FIG>, however it will be understood that the remaining outer sole members may likewise include corresponding inner and outer surfaces that have similar orientations with respect to midsole component <NUM>.

In the exemplary embodiment, inner sole component <NUM> may be disposed within central recess <NUM> of midsole component <NUM>. More specifically, outer surface <NUM> of inner sole component <NUM> may be oriented towards, and be in contact with, inner surface <NUM> of midsole component <NUM>. Furthermore, in some cases, peripheral sidewall surface <NUM> may also contact inner surface <NUM> along an inner recess sidewall <NUM>. In addition, plurality of outer sole members <NUM> may be disposed against outer surface <NUM> of midsole component <NUM>. For example, inner surface <NUM> of first outer sole member <NUM> may face towards, and be in contact with, outer surface <NUM> of midsole component <NUM>. In some embodiments, when assembled, midsole component <NUM> and inner sole component <NUM> could comprise a composite midsole assembly, or dual layered midsole assembly.

In different embodiments, upper <NUM> and sole structure <NUM> could be joined in various ways. In some embodiments, upper <NUM> could be joined to inner sole component <NUM>, e.g., using an adhesive or by stitching. In other embodiments, upper <NUM> could be joined to midsole component <NUM>, for example, along sidewall portion <NUM>. In still other embodiments, upper <NUM> could be joined with both inner sole component <NUM> and midsole component <NUM>. Moreover, these components may be joined using any methods known in the art for joining sole components with uppers, including various lasting techniques and provisions (e.g., board lasting, slip lasting, etc.).

In different embodiments, the attachment configurations of various components of article <NUM> could vary. For example, in some embodiments, inner sole component <NUM> could be bonded or otherwise attached to midsole component <NUM>. Such bonding or attachment could be accomplished using any known methods for bonding components of articles of footwear, including, but not limited to: adhesives, films, tapes, staples, stitching, or other methods. In some other embodiments, it is contemplated that inner sole component <NUM> may not be bonded or attached to midsole component <NUM>, and instead could be free-floating. In at least some embodiments, inner sole component <NUM> may have a friction fit with central recess <NUM> of midsole component <NUM>.

Outer sole members <NUM> may be likewise be bonded or otherwise attached to midsole component <NUM>. Such bonding or attachment could be accomplished using any known methods for bonding components of articles of footwear, including, but not limited to: adhesives, films, tapes, staples, stitching, or other methods.

It is contemplated that in at least some embodiments, two or more of inner sole component <NUM>, midsole component <NUM> and/or outer sole members <NUM> could be formed and/or bonded together during a molding process. For example, in some embodiments, upon forming midsole component <NUM>, inner sole member <NUM> could be molded within central recess <NUM>.

Embodiments can include provisions to facilitate expansion and/or adaptability of a sole structure during dynamic motions.

According to the invention, a sole structure is configured with auxetic provisions. In particular, one or more components of the sole structure is capable of undergoing auxetic motions (e.g., expansion and/or contraction).

Sole structure <NUM> as shown in <FIG> and as described further in detail below, has an auxetic structure or configuration. Sole structures comprising auxetic structures are described in Cross, <CIT> and entitled "Auxetic Structures and Footwear with Soles Having Auxetic Structures" (the "Auxetic Structures application").

As described in the Auxetic Structures application, auxetic materials have a negative Poisson's ratio, such that when they are under tension in a first direction, their dimensions increase both in the first direction and in a second direction orthogonal or perpendicular to the first direction. This property of an auxetic material is illustrated in <FIG>.

As seen in <FIG>, sole structure <NUM> may include a plurality of holes <NUM>. As used herein, the term "hole" refers to any hollowed area or recessed area in a component. In some cases, a hole may be a through hole, in which the hole extends between two opposing surfaces of a component. In other cases, a hole may be a blind-hole, in which the hole may not extend through the entire thickness of the component and may therefore only be open on one side. Moreover, as discussed in further detail below, a component may utilize a combination of through holes and blind-holes. Furthermore, the term "hole" mav be used interchangeably in some cases with "aperture" or "recess".

In regions including one or more holes, sole structure <NUM> may be further associate with a plurality of discrete sole portions <NUM>. Specifically, sole portions <NUM> comprise the portions of sole structure <NUM> that extend between plurality of holes <NUM>. It may also be seen that plurality of holes <NUM> extend between sole portions <NUM>. Thus it may be understood that each hole may be surrounded by a plurality of sole portions, such that the boundary of each hole may be defined by the edges of the sole portions. This arrangement between holes (or apertures) and sole portions, is discussed in further detail in the Auxetic Structures application.

As seen in <FIG>, plurality of holes <NUM> may extend through a majority of midsole component <NUM>. In some embodiments, plurality of holes <NUM> may extend through forefoot portion <NUM>, midfoot portion <NUM> and heel portion <NUM> of midsole component <NUM>. In other embodiments, plurality of holes <NUM> may not extend through each of these portions.

Plurality of holes <NUM> may also extend through plurality of outer sole members <NUM>. In the exemplary embodiment, each of first outer sole member <NUM>, second outer sole member <NUM>, third outer sole member <NUM> and fourth outer sole member <NUM> includes two or more holes. However, in other embodiments, one or more outer sole members may not include any holes.

In different embodiments, the geometry of one or more holes could vary. Examples of different geometries that could be used for an auxetic sole structure are disclosed in the Auxetic Structures application. Moreover, embodiments could also utilize any other geometries, such as utilizing sole portions with parallelogram geometries or other polygonal geometries that are arranged in a pattern to provide the sole with an auxetic structure. In the exemplary embodiment, each hole of plurality of holes <NUM> has a tri-star geometry, including three arms or points extending from a common center.

The geometry of one or more sole portions could also vary. Examples of different geometries that could be used for an auxetic sole structure are disclosed in the Auxetic Structures application. It may be understood that the geometry of a sole portion may be determined by the geometry of the holes in an auxetic pattern, and vice versa. In the exemplary embodiment, each sole portion has an approximately triangular geometry.

Plurality of holes <NUM> may be arranged on sole structure <NUM> in an auxetic pattern, or auxetic configuration. In other words, plurality of holes <NUM> may be arranged on midsole component <NUM> and/or outer sole members <NUM> in a manner that allows those components to undergo auxetic motions, such as expansion or contraction. An example of auxetic expansion, which occurs as the result of the auxetic configuration of plurality of holes <NUM>, is shown in <FIG>. Initially, in <FIG>, sole structure <NUM> is in a non-tensioned state. In this state, plurality of holes <NUM> have an un-tensioned area. For purposes of illustration, only a region <NUM> of midsole component <NUM> is shown, where region <NUM> includes a subset of holes <NUM>.

As tension is applied across sole structure <NUM> along an exemplary linear direction <NUM> (e.g., a longitudinal direction), as shown in <FIG>, sole structure <NUM> undergoes auxetic expansion. That is, sole structure <NUM> expands along direction <NUM>, as well as in a second direction <NUM> that is perpendicular to direction <NUM>. In <FIG>, the representative region <NUM> is seen to expand in both direction <NUM> and direction <NUM> simultaneously, as holes <NUM> increase in size.

<FIG> illustrates a bottom isometric view of sole structure <NUM>, including an enlarged cross-sectional view of midsole component <NUM> and two outer sole members. <FIG> illustrates an exploded bottom isometric view of an embodiment of midsole component <NUM> and outer sole members <NUM>. Referring to <FIG>, each outer sole member may be associated with a corresponding recessed portion in outer surface <NUM> of midsole component <NUM>. Specifically, midsole component <NUM> includes first recessed portion <NUM> for receiving first outer sole member <NUM>; second recessed portion <NUM> for receiving second outer sole member <NUM>; third recessed portion <NUM> for receiving third outer sole member <NUM> and fourth recessed portion <NUM> for receiving fourth outer sole member <NUM>. Each recessed portion may be sized and shaped to fit a corresponding outer sole member. Thus, for example, second recessed portion <NUM> has an outer recess edge <NUM> that has the same shape as outer edge <NUM> of second outer sole member <NUM>.

In some embodiments, an outer sole member could be flush with an outer surface of a midsole component. In the exemplary embodiment, each of outer sole members <NUM> may be flush with midsole component <NUM>. For example, as seen in <FIG>, outer surface <NUM> of first outer sole member <NUM> may be flush with outer surface <NUM> of midsole component <NUM>. Likewise, an outer surface <NUM> of fourth outer sole member <NUM> may be flush with outer surface <NUM>. In a similar manner, both second outer sole member <NUM> and third outer sole member <NUM> may be flush with midsole component <NUM>. This flush configuration may be achieved by having the thickness of each outer sole member approximately equal to the depth of the receiving recessed portion. For example, as shown in <FIG>, first outer sole member <NUM> is seen to have a thickness <NUM> that is approximately equal to a depth <NUM> of first recessed portion <NUM> (see <FIG>). In other embodiments, one or more outer sole members could extend outwardly from a recessed portion. In still other embodiments, the outer surface of an outer sole member could be recessed with respect to outer surface <NUM> of midsole component <NUM>.

As shown in <FIG>, midsole component <NUM> may generally be thicker than each outer sole member. For example, midsole component <NUM> has a thickness <NUM> associated with a thickness of lower portion <NUM> of midsole component <NUM>. In this exemplary embodiment, thickness <NUM> is greater than thickness <NUM>, so that each outer sole member extends into a recess of, but does not extend through the entire thickness of, midsole component <NUM>. This arrangement ensures midsole component <NUM> can provide cushioning and support in portions of sole structure <NUM> associated with outer sole members.

In different embodiments, the materials and/or physical properties of an outer sole member could vary. In some embodiments, an outer sole member could have a relatively high coefficient of friction when compared to a midsole component. For example, in an exemplary embodiment, first outer sole member <NUM> may have a first coefficient of friction with a predetermined material (e.g., wood, laminate, asphalt, concrete, etc.) and midsole component <NUM> may have a second coefficient of friction with the same predetermined material. In some embodiments, the first coefficient of friction is different than the second coefficient of friction. In an exemplary embodiment, the first coefficient of friction is greater than the second coefficient of friction, so that first outer sole member <NUM> provides increased traction (or grip) with the predetermined material than midsole component <NUM>. In at least some embodiments, the predetermined material may be associated with a type of ground surface. For example, the predetermined material could be wood associated with wood flooring in basketball courts. In other embodiments, the predetermined material could be laminate materials that may also be associated with some kinds of courts. In still other embodiments, the predetermined material could be asphalt. In still other embodiments, the predetermined material could be concrete.

Likewise, in some embodiments, each of the remaining outer sole members may also have higher coefficients of friction (relative to a given ground surface) than midsole component <NUM>. This arrangement may allow a user to brake or make cuts by engaging at least one of the outer sole members with a ground surface. It will be understood that in other embodiments, first outer sole member <NUM> could have a coefficient of friction equal to or less than the coefficient of friction of midsole component <NUM>.

It may be appreciated that the coefficient of friction may change according to ambient conditions such as temperature, velocity, etc. Moreover, the coefficients of friction could be different for dry vs. wet conditions. As used herein, the first coefficient of friction and the second coefficient of friction defined for first outer sole member <NUM> and midsole component <NUM>, respectively, may be dry coefficients of friction at standard temperatures and pressures.

Increased friction with a ground surface can be achieved by utilizing materials having higher coefficients of friction and/or by providing surface features that enhance grip with the ground. Such features could include tread elements such as ridges, hemispheric protrusions, cylindrical protrusions as well as other kinds of tread elements. In the exemplary embodiment, first outer sole member <NUM> is provided with a plurality of ridge elements <NUM>, which may be best seen in <FIG>. In contrast, outer surface <NUM> of midsole component <NUM> may be seen to have a relatively smooth surface.

In different embodiments, the densities of an outer sole member and/or a midsole component could vary. In some embodiments, an outer sole member may have a higher density than a midsole component, thereby allowing for increased durability and wear resistance for the outer sole member. In other embodiments, however, the density of the outer sole member could be equal to the density of the midsole component, or could be less than the density of the midsole component.

Outer sole members could be manufactured from a variety of different materials. Exemplary materials include, but are not limited to: rubber (e.g., carbon rubber or blown rubber), polymers, thermoplastics (e.g., thermoplastic polyurethane), as well as possibly other materials. In contrast, midsole components may generally be manufactured from polyurethane, polyurethane foam, other kinds of foams as well as possibly other materials. It will be understood that the type of materials for outer sole members and a midsole component could be selected according to various factors including manufacturing requirements and desired performance characteristics. In an exemplary embodiment, suitable materials for outer sole members <NUM> and midsole component <NUM> could be selected to ensure outer sole members <NUM> have a larger coefficient of friction that midsole component <NUM>, especially when these components are in contact with hardwood surfaces, laminate surfaces, asphalt, as well as other surfaces where article of footwear <NUM> may be most commonly used.

<FIG> and <FIG> illustrate a region <NUM> of sole structure <NUM> in an un-tensioned state (<FIG>) and a tensioned state (<FIG>). Thus, plurality of holes <NUM> are seen to open up (e.g., increase in opening or cross-sectional area) as sole structure <NUM> undergoes auxetic expansion due to tension <NUM>. It is clear from <FIG> that region <NUM> expands both in the direction of tension <NUM> as well as in a direction <NUM>, which is perpendicular to the direction of tension <NUM>.

Embodiments may include provisions for ensuring the auxetic behavior of sole structure <NUM> is uniform, even across different portions or materials. In some embodiments, openings in one or more outer sole members may be aligned with openings in a midsole component.

Referring to <FIG>, and according to the invention, region <NUM> of sole structure <NUM> includes a first portion <NUM> and a second portion <NUM> of the outer surface of sole structure <NUM>. Specifically, first portion <NUM> is a portion of outer surface <NUM> of first outer sole member <NUM>, while second portion <NUM> is a portion of outer surface <NUM> of midsole component <NUM>. Region <NUM> further comprises a set of holes <NUM> arranged in an auxetic configuration, which are a subset of plurality of holes <NUM>.

As seen in <FIG>, the auxetic configuration of set of holes <NUM> extends without interruption, or continuously, from first portion <NUM> of region <NUM> to second portion <NUM>. In other words, the auxetic configuration of set of holes <NUM> extends without interruption between first outer sole member <NUM> and midsole component <NUM>. As used herein, and according to the invention, an auxetic configuration extends continuously or without interruption through a region if the pattern of holes (including the shapes, relative orientations of holes and spacing between holes) does not vary significantly throughout the region. Such an uninterrupted or continuous configuration is important because interruptions or breaks in the auxetic configuration or pattern of holes <NUM> could result in changes to, or deviations from, the desired auxetic motion or dynamics.

The continuation of the auxetic configuration or pattern between first portion <NUM> and second portion <NUM> is exemplified by considering several representative holes. As seen in <FIG>, a first hole <NUM> of set of holes <NUM> is disposed in first portion <NUM> of first outer sole member <NUM>. A second hole <NUM> of set of holes <NUM> is disposed in second portion <NUM> of midsole component <NUM>. Both first hole <NUM> and second hole <NUM> are surrounded by six sole portions and by six adjacent holes. In addition, the orientations of first hole <NUM> and second hole <NUM>, with respect to sole structure <NUM>, are similar. Also, the pattern and spacing of the six adjacent holes around first hole <NUM> is similar to the pattern and spacing of six adjacent holes around second hole <NUM>. Moreover, first hole <NUM> and second hole <NUM> have an approximately similar shape, specifically a tri-star shape.

The continuity of the auxetic configuration occurs even at the boundary between first portion <NUM> and second portion <NUM> (e.g., between first outer sole member <NUM> and midsole component <NUM>). For example, a third hole <NUM> extends through both first portion <NUM> and second portion <NUM>. Third hole <NUM> includes a first arm <NUM>, a second arm <NUM> and a third arm <NUM>. Further, third hold <NUM> is comprised of a first hole portion <NUM> that includes second arm <NUM> and third arm <NUM> as well as a part of first arm <NUM>. Third hole <NUM> also includes a second hole portion <NUM> that includes the tip of first arm <NUM>. As seen in <FIG>, first hole portion <NUM> is disposed in second portion <NUM> and is continuous with second hole portion <NUM>, which is disposed in first portion <NUM>.

In at least some embodiments, the edges of an outer sole member could correspond with the auxetic configuration of holes. In particular, one or more edges of an outer sole member could be aligned with a direction defined by the orientations of two or more holes.

As seen in <FIG>, for example, an edge <NUM> of first outer sole member <NUM> may be aligned with a direction defined by the orientation of plurality of holes <NUM>. Specifically, plurality of holes according to the invention is arranged such that each hole includes an arm oriented in a direction characterized by first axis <NUM>. For example, hole <NUM> and hole <NUM> both each have an arm oriented along first axis <NUM>. Additionally, each of the holes in plurality of holes <NUM> has an arm oriented along or parallel to first axis <NUM>. In the exemplary embodiment, edge <NUM> may be parallel with first axis <NUM>. In a similar manner, in some embodiments, each edge of each outer sole member may be approximately aligned with a direction defined by the orientation of the holes (i.e., by the directions defined by each arm of the holes). In still some embodiments, some edges may be aligned with directions defined by the holes, while other edges may not be aligned with these directions. By aligning edges of each outer sole member with directions defined by the auxetic configuration, the outer sole members may be placed on sole structure <NUM> in a manner that does not interfere with the auxetic structure of the sole.

<FIG> illustrates a bottom view of another embodiment of a sole structure <NUM>. Referring to <FIG>, sole structure <NUM> may include an inner sole component (not visible), a midsole component <NUM> and a plurality of outer sole members <NUM>. Each of these components could share similar provisions to corresponding components of the earlier embodiments, namely inner sole component <NUM>, midsole component <NUM> and plurality of outer sole members <NUM>.

Outer sole members <NUM> may be configured in various locations on a lower portion <NUM> of midsole component <NUM>. For example, the exemplary embodiment includes a first outer sole member <NUM> disposed at front end portion <NUM> of midsole component <NUM>. A second outer sole member <NUM> is disposed within forefoot portion <NUM> of midsole component <NUM>. In addition, a third outer sole member <NUM> and a fourth outer sole member <NUM> are disposed in heel portion <NUM> of midsole component <NUM>. These exemplary locations may provide for an alternative traction profile, as compared to the embodiments shown in <FIG>. Specifically, the embodiment of <FIG> includes first outer sole member <NUM> which provides enhanced traction over the entire forward edge of sole structure <NUM>, as well as third outer sole component <NUM>, which provides enhanced traction adjacent the ball of the foot.

It may be appreciated that the locations of one or more outer sole members could be varied in other embodiments. In some cases, the locations could be selected according to desired locations on the sole structure for enhancing traction. In other cases, the locations could be selected so as to avoid interference with auxetic expansion of the midsole component in certain regions portions, such as the midfoot portion <NUM> of midsole component <NUM>.

In different embodiments, the shapes of outer sole members could vary. For example, the exemplary embodiment includes outer sole members that entirely cover midsole component <NUM> (e.g., first outer sole member <NUM>, third outer sole member <NUM> and fourth outer sole member <NUM>). Likewise, the exemplary embodiment includes outer sole members with apertures that expose portions of midsole component <NUM> (e.g., second outer sole member <NUM>, which includes apertures <NUM>). Moreover, the exemplary embodiment depicts outer sole members that have patterns or arrangements generally corresponding with the pattern or arrangement of openings on midsole component <NUM>.

Midsole component <NUM> is configured with a plurality of holes <NUM> that are arranged in an auxetic configuration. In the exemplary embodiment of <FIG>, plurality of holes <NUM> may be similar in one or more respects to holes of the embodiments shown in <FIG>. In particular, some holes may be through holes, while other holes may be blind holes. Likewise, at least two different holes of plurality of holes <NUM> could differ in opening size or cross-sectional area. As in previous embodiments, the arrangement of holes throughout midsole component <NUM> may be selected to achieve desired auxetic properties for sole structure <NUM>.

Embodiments may include provisions for enhancing traction on a bottom or lower surface of a sole structure. In some embodiments, a sole structure may be provided with one or more tread elements. As used herein, the term "tread element" refers to a feature that extends outwardly on a ground engaging surface of a sole structure so as to engage the ground surface and provide increased traction.

As shown in <FIG>, sole structure <NUM> has a ground engaging surface <NUM>, which is comprised of the outermost surfaces of midsole component <NUM> and of plurality of outer sole members <NUM>. Ground engaging surface <NUM> may further include plurality of raised tread elements <NUM>.

Tread elements <NUM> may be associated with sole portions of midsole component <NUM>. For example, a first tread element <NUM> is approximately centered on first sole portion <NUM>. In an exemplary embodiment, the majority of sole portions may include an associated tread element. Moreover, the tread elements are arranged around each hole in a manner similar to the sole members. For example, a first hole <NUM> is surrounded by first sole portion <NUM>, second sole portion <NUM>, third sole portion <NUM>, fourth sole portion <NUM>, fifth sole portion <NUM> and sixth sole portion <NUM>. Each sole portion has a corresponding tread element, so that second tread element <NUM>, third tread element <NUM>, fourth tread element <NUM>, fifth tread element <NUM> and sixth tread element <NUM> are disposed on second sole portion <NUM>, third sole portion <NUM>, fourth sole portion <NUM>, fifth sole portion <NUM> and sixth sole portion <NUM>, respectively. Thus, it may be understood that as each sole portion rotates under auxetic expansion the tread elements also rotate, thereby increasing frictional drag with a ground surface during the expansion.

In different embodiments, the geometry of a tread element could vary. Exemplary shapes include, but are not limited to: triangular geometries, rectangular geometries, polygonal geometries, circular geometries, rounded geometries, non-linear geometries, irregular geometries and/or any other kinds of geometries. In the exemplary embodiment of <FIG>, tread elements <NUM> have a triangular geometry that corresponds with the outer boundary geometry of the sole portions (e.g., the triangular boundary of a seventh sole portion <NUM> matches a corresponding triangular geometry of seventh tread element <NUM>).

Each raised tread element of tread elements <NUM> may be raised, or protrude from, the outer surface of sole structure <NUM>. Thus, each raised tread element may form a prism-like structure extending from sole structure <NUM>.

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 appended claims.

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.

Claim 1:
An article of footwear (<NUM>), comprising:
a sole structure (<NUM>) including a midsole component (<NUM>) and at least one outer sole member (<NUM>);
the midsole component (<NUM>) including a first outer surface (<NUM>) with a recessed portion (<NUM>);
the outer sole member (<NUM>) having a second outer surface (<NUM>);
wherein the recessed portion (<NUM>) is configured to receive the outer sole member (<NUM>);
a region (<NUM>) of the sole structure (<NUM>) including a first portion (<NUM>) in the first outer surface (<NUM>) of the midsole component (<NUM>) and a second portion (<NUM>) in the second outer surface (<NUM>) of the outer sole member (<NUM>);
the region (<NUM>) including a set of holes (<NUM>) arranged in an auxetic configuration, wherein the region is configured to undergo auxetic expansion when a tension is applied across the region in a first direction, wherein the region expands in the first direction and a second direction during auxetic expansion, the second direction being perpendicular to the first direction;
wherein the auxetic configuration of the holes does not vary throughout the region (<NUM>); and
wherein the set of holes (<NUM>) is arranged such that each hole includes an arm oriented in a direction characterized by a first axis (<NUM>).