Patent Description:
Footwear articles often include one or more sole structures that provide various functions. For instance, a sole structure generally protects a wearer's foot from environmental elements and from a ground surface. In addition, a sole structure may attenuate an impact or a force caused by a ground surface or other footwear-contacting surfaces.

<CIT> describes a shock-absorbing device particularly for shoes, comprising, included within the mid-sole, at least at the heel region, a plurality of hollow elements, made of elastomer and connected by bridges, each whereof is internally shaped so as to form, upon assembly, two superimposed chambers which are mutually connected by a duct; the duct has a smaller cross-section than the chambers and forms a constriction for passing air flows.

This subject matter is described in detail herein with reference to drawing figures, which are incorporated herein by reference in their entirety.

Each of <FIG> depicts a respective view of a sole in accordance with an aspect of this disclosure.

Each of <FIG> depicts a respective view of a footwear article having a sole structure in accordance with an aspect of this disclosure.

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

Subject matter is described throughout this Specification in detail and with specificity in order to meet statutory requirements. The aspects described throughout this Specification are intended to be illustrative rather than restrictive, and the description itself is not intended necessarily to limit the scope of the claims.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by, and is within the scope of, the claims.

The subject matter described in this Specification generally relates to, among other things, a support structure for a footwear sole, a support system having the support structures for a footwear sole, a footwear sole including the support system, a footwear article, a method of making any of the foregoing, and any combination thereof. An exemplary footwear article <NUM> having a system of support structures is depicted in <FIG>. The footwear article includes a sole <NUM>, and the sole <NUM> includes a plurality of support structures arranged across various regions of the sole <NUM>. One of the support structures is identified with reference numeral <NUM>, and the other support structures might include a same or similar construction.

The system of support structures might be organized into various types of arrangements, such as a matrix or an array including multiple stacked, offset rows of support structures. As described in other parts of this disclosure, the support structures (e.g., support structure <NUM>) operate at an individual structure level, as well as collectively as a system, to provide various functionality for a footwear article. Some of that functionality provided by the sole <NUM> is generally described in this portion of the disclosure, and subsequent portions of the disclosure provide additional details explaining some of the various aspects and how they operate to provide the functionality. For example, in accordance with aspects of this disclosure, a footwear sole structure may in some instances provide a cushioning functionality, in which the sole absorbs at least a portion of a force, such as by compressing, buckling, collapsing, or any combination thereof, when a wearer's foot strikes a ground surface (e.g., when walking, running, jumping, and the like). In some other instances, the footwear sole structure may also provide an energy-return functionality, in which the sole stores elastic potential energy when absorbing the force and releases kinetic energy upon removal of the force.

As described in more detail in other parts of this disclosure, in accordance with aspects of this disclosure, various factors might contribute to the cushioning functionality and energy-return functionality, such as the configuration of a support structure, the arrangement of a system of support structures, the material(s) from which support structures are constructed, or any combination thereof. In contrast to some traditional sole technology, such as foam soles or alternative cell-based systems, aspects of this disclosure describe a system of support structures that provide cushioning and energy return and that might be lighter weight. In some instances, the lighter weight property (e.g., relative to some traditional foam soles or alternative cell-based systems) results from using less material, since the configuration of each support structure, and the support structures collectively, contributes cushioning and energy return, such that the functioning of the sole is not reliant on only the material properties of the base foam material. Stated differently, some traditional foam soles rely primarily on the material properties of the underlying foam to provide cushioning and energy return, and in contrast, aspects of this disclosure leverage the functional properties of the support structures and support-structure system (in addition to material properties), which allows the use of less material. Furthermore, as compared with alternative cell-based structures that might also utilize 3D-printed structures, the support structures and support-structure systems of this disclosure provide improved cushioning and energy return, which again allows for a materials reduction by reducing cell wall thickness, numbers of cells, and the like while maintaining functionality.

In <FIG>, the footwear article <NUM> includes a sole <NUM> and an upper <NUM>. The upper <NUM> and the sole <NUM> generally form a foot-receiving space that encloses at least part of a foot when the footwear is worn or donned. That is, typically a portion of the upper overlaps with, and is connected to, a portion of the sole <NUM>. This overlapping region, and the resulting coupling mechanism (e.g., stitching, bonding, adhering, integrally forming, co-molding, etc.), is sometimes referred to as a "biteline. " The foot-receiving space is accessible by inserting a foot through an opening formed by the ankle collar <NUM>. When describing various aspects of the footwear <NUM>, relative terms may be used to aid in understanding relative positions. For instance, the footwear <NUM> may be divided into three general regions: a forefoot region <NUM>, a mid-foot region <NUM>, and a heel region <NUM>. The footwear <NUM> also includes a lateral side, a medial side, a superior portion, and an inferior portion.

The forefoot region <NUM> generally includes portions of the footwear <NUM> corresponding with the toes and the joints connecting the metatarsals with the phalanges. The mid-foot region <NUM> generally includes portions of footwear <NUM> corresponding with the arch area of the foot, and the heel region <NUM> corresponds with rear portions of the foot, including the calcaneus bone. In addition, portions of a footwear article may be described in relative terms using these general zones. For example, a first structure may be described as being more heelward than a second structure, in which case the second structure would be more toeward and closer to the forefoot. Further, a coronal or transverse plane of the shoe, spaced an equidistance between the forward-most point of the forefoot region and the rearward-most point of the heel region, may be used to describe relational qualities of some parts of a shoe.

The lateral side and the medial side extend through each of regions <NUM>, <NUM>, and <NUM> and correspond with opposite sides of footwear <NUM>. More particularly, the lateral side corresponds with an outside area of the foot (i.e., the surface that faces away from the other foot), and the medial side corresponds with an inside area of the foot (i.e., the surface that faces toward the other foot). In addition, these terms may also be used to describe relative positions of different structures. For example, a first structure that is closer to the inside portion of the footwear article might be described as medial to a second structure, which is closer to the outside area and is more lateral. In other aspects, a sagittal or parasagittal plane of the shoe, may be used to describe relational qualities of some parts of a shoe. Furthermore, the superior portion and the inferior portion also extend through each of the regions <NUM>, <NUM>, and <NUM>, and the terms superior and inferior may also be used in relation to one another. For example, the superior portion generally corresponds with a top portion that is oriented closer towards a person's head when the person's feet are positioned flat on a horizontal ground surface and the person is standing upright, whereas the inferior portion generally corresponds with a bottom portion oriented farther from a person's head and closer to the ground surface. A transverse plane of the shoe may be used in some aspects of describe relational qualities of some parts of a shoe. These regions <NUM>, <NUM>, and <NUM>, sides, and portions are not intended to demarcate precise areas of footwear <NUM>. They are intended to represent general areas of footwear <NUM> to aid in understanding the various relative descriptions provided in this Specification. In addition, the regions, sides, and portions are provided for explanatory and illustrative purposes and are not meant to require a human being for interpretive purposes. Although <FIG> depicts one certain style of footwear, such as footwear worn when engaging in athletic activities (e.g., cross-training shoes, running shoes, walking shoes, and the like), the subject matter described herein may be used in combination with other styles of footwear, such as dress shoes, sandals, loafers, boots, and the like.

The sole <NUM> might comprise various components. For example, the sole <NUM> may comprise an outsole with tread or traction elements made of a relatively hard and durable material, such as rubber or durable foam that contacts the ground, floor, or other surface. The sole <NUM> may further comprise a midsole formed from a material that provides cushioning and absorbs force during normal wear and/or athletic training or performance. Examples of materials often used in midsoles are, for example, ethylene vinyl acetate (EVA), thermoplastic polyurethane (TPU), thermoplastic elastomer (e.g., polyether block amide), and the like. Shoe soles may further have additional components, such as additional cushioning components (such as springs, air bags, and the like), functional components (such as motion control elements to address pronation or supination), protective elements (such as resilient plates to prevent damage to the foot from hazards on the floor or ground), and the like. As previously indicated, an aspect of the present disclosure includes a midsole having a system of support structures (e.g., support structure <NUM>).

Referring to <FIG>, the support structure <NUM> is illustrated in accordance with one aspect of this disclosure, and <FIG> depict cross-sectionals views of the support structure <NUM> taken at the reference 3A-3A and 3B-3B identified in <FIG>. In <FIG>, the support structure <NUM> is depicted as a discrete element, separate from the sole <NUM> in <FIG>, and one aspect of the present disclosure is directed to the discrete support structure <NUM>, either independently from, or included in, a sole. The support structure <NUM> includes a tubular body <NUM> including a wall <NUM> that partially encloses a hollow cavity <NUM> and that extends circumferentially around a reference axis <NUM>. As used in this disclosure, a reference axis is a reference line that passes through the hollow cavity <NUM> at a series of points equidistant between opposing sides of an interior surface <NUM>. The wall <NUM> includes an exterior surface <NUM> facing away from the hollow cavity <NUM>, the interior surface <NUM> facing towards the hollow cavity <NUM>, and a wall thickness <NUM> between the exterior surface <NUM> and the interior surface <NUM>.

The tubular body <NUM> includes a first end <NUM> and a second end <NUM> that are spaced apart in the axial direction, and the support structure <NUM> includes a height <NUM> measured from the first end <NUM> to the second end <NUM>. The tubular body <NUM> is open at the first end <NUM> and the second end <NUM>, such that the wall <NUM> does not enclose these portions of the tubular body <NUM>. In addition, the tubular body <NUM> includes one or more diameters (e.g., <NUM>, <NUM>, <NUM>, and <NUM>) that might vary from one portion of the tubular body to another.

Size, shape, dimensions, and other elements of the support structure might be described, defined, or prescribed in various manners. In addition, as will be described in other portions of this disclosure, the wall thickness <NUM>, the height <NUM>, and other characteristics might vary depending on various factors. For explanatory purposes, some aspects of these features will be described in this portion of the disclosure with reference to <FIG>, and these aspects may be revisited and expanded upon in other parts of the disclosure.

In one aspect of the disclosure, the tubular-wall thickness <NUM> is in a range of about <NUM> to about <NUM>. In a further aspect, the tubular-wall thickness <NUM> is in a range of about <NUM> to about <NUM>. In a further aspect, the tubular-wall thickness <NUM> is in a range of about <NUM> to about <NUM>. In still a further aspect, the tubular-wall thickness <NUM> is about <NUM>. In yet another aspect, the tubular-wall thickness <NUM> is about <NUM>. These are examples of some aspects of the tubular-wall thickness <NUM>, which may vary based on various factors and considerations as will be described in other parts of this disclosure. In other aspects, the tubular-wall thickness <NUM> may be less than these described ranges, or may be greater than these described ranges.

The support structure <NUM> also includes the height <NUM> measured from the first end <NUM> to the second end <NUM>. In one aspect of the disclosure, the height <NUM> is in a range of about <NUM> to about <NUM>. In a further aspect, the height <NUM> is in a range of about <NUM> to about <NUM>. In still a further aspect, the height <NUM> is about <NUM>. In yet another aspect, the height <NUM> is about <NUM>. These are examples of some aspects of the height <NUM>, which may vary based on various factors and considerations as will be described in other parts of this disclosure. In other aspects, the height <NUM> may be less than these described ranges, or may be greater than these described ranges.

As depicted in <FIG>, the wall <NUM> curves inward as the wall <NUM> continuously extends between the first end <NUM> and the second end <NUM>. The curve of the wall, as well as the resulting overall structure of the wall surfaces, might be described in various manners. Furthermore, the curvature of the wall <NUM> may vary in different aspects. For example, the tubular wall <NUM> includes the interior surface <NUM> facing towards the cavity <NUM>, and in one aspect, the interior surface <NUM> is convex as it extends from the first end <NUM> to the second end <NUM>, as depicted in <FIG>. Furthermore, the interior surface <NUM> maintains a convex nature from the first end <NUM> to the second end <NUM> as the interior surface <NUM> extends around the reference axis <NUM>. In addition, as depicted in <FIG>, the interior surface <NUM> is concave in a cross-sectional plane extending perpendicular to the axis as the wall <NUM> extends around the axis <NUM>. The tubular wall <NUM> also includes the exterior surface <NUM> facing away from the cavity <NUM>, and in another aspect, the exterior surface <NUM> is concave as the exterior surface <NUM> extends from the first end <NUM> to the second end <NUM>. Similar to the interior surface <NUM>, the exterior surface <NUM> maintains a concave nature from the first end <NUM> to the second end <NUM> as the exterior surface <NUM> extends around the reference axis <NUM>. Moreover, depicted in <FIG>, the exterior surface <NUM> is convex in a cross-sectional plane extending perpendicular to the axis <NUM> as the wall <NUM> extends around the axis <NUM>.

Because of the tubular nature of the support structure <NUM>, the wall <NUM> includes an interior diameter, and the interior diameter gradually changes from the first end <NUM> to the second end <NUM>. That is, at each end of the support structure <NUM>, the interior diameter includes a respective value, and the interior diameter gradually decreases as the wall <NUM> extends away from the ends and curves towards a middle region <NUM> of the tubular body <NUM>. For example, <FIG> depicts a first diameter <NUM> of the interior surface <NUM> at the first end <NUM>, a second diameter <NUM> that is smaller than the first diameter <NUM>, and a third diameter <NUM> that is smaller than the second diameter <NUM>. In one aspect, each end of the tubular body <NUM> includes a rim <NUM>, which includes a circumferential portion of the interior surface having a largest diameter before the interior surface either flattens out into a plane or transitions to another structure (as will be describe in subsequent portions). In aspects of this disclosure, the diameters of the tubular body <NUM> may vary. For example, in one aspect, the largest diameter <NUM> at the rim of each end (i.e., interior diameter) is in a range of approximately <NUM> to approximately <NUM>, and a narrowest interior diameter <NUM> of the tubular body (e.g., between the ends <NUM> and <NUM>) is in a range of approximately <NUM> to approximately <NUM>. In light of the range of heights <NUM> identified above, in one aspect of the disclosure, the support structure <NUM> includes a height <NUM> to rim diameter <NUM> in a range of approximately <NUM>: <NUM> to approximately <NUM>: <NUM>.

In one aspect of the disclosure, the curvature of the exterior surface <NUM> extending from the first end <NUM> to the second end <NUM> is a simple curve with a constant radius. In another aspect, the curvature of the exterior surface <NUM> extending from the first end <NUM> to the second end <NUM> is a complex curve with a plurality of different radii. In a further aspect, the curvature of the interior and exterior surfaces remains relatively constant as wall <NUM> circumscribes the hollow cavity <NUM>. In one aspect, in which the curvature of the exterior surface <NUM> satisfies a definition for a catenary curve, the tubular body <NUM> might form a catenoid. In another aspect, the tubular body <NUM> might form a helicoid.

The configuration of the exterior surface <NUM>, including various qualities such as size and shape, might be determined or defined in other manners. In one aspect of the present disclosure, the exterior surface of the support structure <NUM> is a minimal surface. In general, a minimal surface includes a zero mean curvature, and a minimal surface may be defined by an equation. Among other things, by using a minimal-surface geometry with curved surfaces for the support structure, force load applied to the support structure <NUM> might be more evenly distributed throughout the continuous surface of the entire system, as opposed to greater axial distribution that might otherwise occur, such as with struts that intersect one another. In a further aspect, an equation "E1" defining the minimal surface of the exterior surface <NUM> includes: <MAT>.

In an aspect of this disclosure, the elements of the support structure <NUM>, such as dimensions and configuration (e.g., curvature of wall), affect the contribution of the support structure to the cushioning functionality of a footwear sole. For example, the dimensions and configuration might affect the rate and consistency at which the support structure <NUM> compresses under load. Furthermore, the dimensions and configuration might affect the amount of force at which the support structure <NUM> undergoes an increased rate of compression, similar to a collapsing action, or bottoming out. For example, the omission of flat or planar surfaces, as well as corners, joints, and junctions in the support structure <NUM>, might reduce the likelihood that a compression force will be focused on a fewer number of positions when the support structure is under load, and in this respect, a compression force may be more evenly distributed throughout the entire support structure <NUM>. For example, when a configuration of the exterior surface is a minimal surface, the force-load might be distributed across the entire area of the surface as opposed to a strut-based surface in which the force-load may concentrate in the cross sections of the strut. Among other things, a strut-based system may experience failure in the structure due to repeated bending of the strut elements at positions that bear a larger portion of the force-load.

In another aspect, the structure of the support structure <NUM> factors into the ability of the support structure <NUM> to be coupled with other support structures, in a manner that allows the combination of support structures to also contribute to the cushioning functionality. In these respects, the support structure <NUM> includes features and elements as a basic unit or cell that are important to the functionality of a system as a whole (e.g., system of support structures in a footwear sole), and some of the subsequent aspects of this disclosure provide additional explanation as to how a system of support structures may contribute to the footwear-sole functionality.

The support structure <NUM> may be coupled to one or more other similarly shaped support structures in a support-structure system, which might be configured for integration into a footwear sole. The system of support structures might be organized into various arrangements of rows, columns, matrices, arrays, and the like. For example, referring to <FIG>, a system <NUM> of support structures is depicted including a first support structure <NUM>, a second support structure <NUM>, and a third support structure <NUM>. The first support structure <NUM> and the third support structure <NUM> are positioned in a same row <NUM> of support structures, whereas the second support structure <NUM> is positioned in a second row <NUM> that is staggered relative to the first row <NUM>. For illustrative purposes, <FIG> depicts a cross-sectional view taken at reference plane 5A-5A identified in <FIG>, and <FIG> depicts a cross-sectional view taken at reference plane 5B-5B identified in <FIG>.

As illustrated in the cross-section depicted in <FIG>, the axis <NUM> of the first support structure <NUM> in the first row <NUM> is not coaxial along a common axis with the axis <NUM> of the second support structure <NUM> in the second row <NUM>. In this sense, the axis <NUM> is laterally (or horizontally) offset from the axis <NUM> (i.e., laterally being opposite or perpendicular to the general longitudinal orientation of the axis). The first and second support structures <NUM> and <NUM> are also laterally offset from one another. In addition, the first and second support structures <NUM> and <NUM> themselves are longitudinally (or vertically) offset, in the longitudinal direction of the axes. As used herein, the term vertical or vertically refers only to the up-and-down orientation relative to the depiction of <FIG> on the page, and vertically does not necessarily refer to the orientation when the support structures <NUM> and <NUM> are integrated into a footwear sole. In addition, horizontal or horizontally refers only to the side-to-side orientation relative to the depiction of <FIG> on the page and does not necessarily refer to the orientation when the support structures <NUM> and <NUM> are integrated into a footwear sole.

The relationship between the first support structure <NUM> and the second support structure <NUM> may include additional features or characteristics relating to, and contributing to, at least a portion of the system <NUM>. Furthermore, both the first support structure <NUM> and the second support structure <NUM> may include elements consistent with the support structure <NUM> described in relation to <FIG>, and some of these elements are identified in <FIG> and <FIG>. As such, the first support structure <NUM> and the second support structure <NUM> may each include a tubular body including a wall <NUM> and <NUM> that at least partially encloses a hollow cavity <NUM> and <NUM> and that extends circumferentially around the hollow cavity and the reference axis <NUM> and <NUM>. In addition, the tubular body of each of the first support structure <NUM> and the second support structure <NUM> may include a first end <NUM> and <NUM> and a second end <NUM> and <NUM> that are spaced apart in an axial direction. Furthermore, the wall <NUM> and <NUM> of each of the support structures may curve inward as the wall extends between the first end and the second end, and the wall may include an exterior surface <NUM> and <NUM> facing away from the hollow cavity and an interior surface <NUM> and <NUM> facing towards the hollow cavity. The support structures <NUM> and <NUM> may include any of the additional elements described with respect to <FIG>, either independently of one another, or collectively.

As described above, the rows <NUM> and <NUM> are staggered, being laterally offset and arranged end-to-end. Accordingly, in one aspect (as illustratively depicted in the cross section of <FIG>), the first support structure <NUM> is partially stacked atop, and staggered relative to, the second support structure <NUM>. Furthermore, one or more surfaces continuously extend from the first support structure <NUM> to the second support structure <NUM> to construct respective surface portions of each structure's tubular wall. For example, the dashed reference line <NUM> (<FIG>) is illustrated on a single continuous surface including both a first portion of the exterior surface <NUM> of the first support structure <NUM> and a first portion of the interior surface <NUM> of the second support structure <NUM>. In this manner, the dashed reference line <NUM> illustrates a manner in which the single continuous surface transitions from an exterior surface <NUM> of one support structure <NUM> to an interior surface <NUM> of another support structure <NUM>. In a complimentary manner on an opposite side of the walls <NUM> and <NUM> (obscured from view in <FIG>), a single surface continuously forms, and extends from, the interior surface <NUM> of the support structure <NUM> to the exterior surface <NUM> of support structure <NUM>.

These aspects are also illustrated in the cross section depicted in <FIG>, and the reference plane at which the cross section 5A-5A is taken is aligned with the reference line <NUM>. As such, <FIG> illustrates a first exterior-surface portion <NUM> of the first support structure <NUM> that is continuous with a first interior-surface portion <NUM> of the second support structure <NUM>. Furthermore, the first exterior-surface portion <NUM> includes a concave curvature extending between the first end <NUM> and the second end <NUM>, and the first interior-surface portion <NUM> includes a convex curvature extending between the first end <NUM> and the second end <NUM>. As explained above, the single continuous surface transitions from the exterior-surface portion <NUM> to the interior-surface portion <NUM>. In a complimentary manner, <FIG> illustrates an interior-surface portion <NUM> (convex as it extends between the first end <NUM> and the second end <NUM>) of the first support structure <NUM> being continuous with an exterior-surface portion <NUM> (concave as it extends between the first end <NUM> and the second end <NUM>) of the second support structure <NUM>.

In one aspect of the disclosure, the first support structure <NUM> has a second-end rim <NUM>, including a circumferential portion of the interior surface <NUM>, and an edge of the second-end rim <NUM> abuts a junction <NUM> with the exterior-surface portion <NUM> (i.e., the portion at which the interior-surface portion <NUM> transitions to the exterior-surface portion <NUM>). In addition, the second support structure <NUM> includes a first-end rim <NUM>, including a circumferential portion of the interior surface <NUM>, and an edge of the first-end rim <NUM> abuts a junction <NUM> with the exterior-surface portion <NUM> (i.e., the portion at which the interior-surface portion <NUM> transitions to the exterior-surface portion <NUM>). As explained with reference to <FIG>, the second-end rim <NUM> and the first-end rim <NUM> each includes a respective diameter. In a further aspect of the disclosure, the axis <NUM> and <NUM> of the first support structure <NUM> and the second support structure <NUM> are offset by a distance <NUM> that is equal to an average of the diameters of the second-end rim <NUM> and the first-end rim <NUM>. Moreover, the junctions <NUM> and <NUM> might be directly opposite one another on either side of the wall in a plane <NUM> running parallel with both axis.

The junction (e.g., <NUM> or <NUM>), or the point at which one surface transitions to another surface (e.g., the point at which exterior portion <NUM> transitions to interior portion <NUM>), might be identified in a various manners. For example, in one aspect of this disclosure, the transition point is located at the position at which a concave exterior surface changes to a convex interior surface. In another aspect, the transition point is located at the position at which a convex interior surface changes to a concave exterior surface. In other aspects, a flat surface may extend between and connect a concave surface and a convex surface, and in that instance, the junction (i.e., transition point) is at the midpoint between the convex surface and the concave surface.

As explained in other portions of this disclosure, the exterior surface of the support structures might include a minimal surface. Among other things, a minimal-surface geometry may help distribute a load more evenly throughout the entire system <NUM> - such as a load applied generally in the axial direction or otherwise. Accordingly, in one aspect the exterior surfaces <NUM> and <NUM>, including the portions <NUM> and <NUM>, might both include portions of a minimal-surface structure. For example, the exterior surfaces <NUM> and <NUM> of both support structures <NUM> and <NUM> might include a catenoid or a helicoid. In one aspect, the exterior surfaces are defined by the equation E1. Furthermore, as explained above, the structure of the support structure <NUM> factors into the ability of the support structure <NUM> to be coupled with other support structures, in a manner that allows the combination of support structures to also contribute to the cushioning functionality. This aspect is at least partially illustrated by the reference line <NUM> showing the continuous surface that smoothly transitions from one support structure <NUM> to another support structure <NUM>. This aspect is also illustrated by the cross-sectional view of <FIG> showing the smooth transition from the wall <NUM> to the wall <NUM>. The smooth transition minimizes corners or other wall junctions that might otherwise create unequal load distribution. That is, this continuous and smooth transition between support structures helps to reduce the likelihood that a compression force will be focused at fewer locations (e.g., wall joints) and to allow the compression force to be more evenly distributed throughout the entire system of support structures.

<FIG> and <FIG> also help to show a relationship between the first support structure <NUM> and the third support structure <NUM>, which are arranged side-by-side, such that the axes <NUM> and <NUM> are laterally (or horizontally) offset and are not coaxial along a same axis. But the structures <NUM> and <NUM> themselves are not longitudinally or vertically offset from one another or stacked in an end-to-end manner. That is, as between the structures <NUM> and <NUM>, the rims of at least one of the structures lie in respective planes that are either aligned with a rim of the other structure or are between the rims of the other structure. Support structures that are not laterally axially aligned have axes that are either parallel or skew and are not coaxial.

The third support structure <NUM> might likewise include the elements described with respect to <FIG>, such as a wall, first end, second end, interior surface, exterior surface, wall thickness, height, curvature, etc. Furthermore, one or more surfaces continuously extend from the first support structure <NUM> to the third support structure <NUM> to construct respective surface portions of each structure's tubular wall. For example, the dashed reference line <NUM> is illustrated on a single continuous surface and is aligned with the reference plane 5B-5B. <FIG> illustrates a second exterior-surface portion <NUM> of the first support structure <NUM> that is continuous with an exterior-surface portion <NUM> of the third support structure <NUM>. Furthermore, the exterior-surface portions <NUM> and <NUM> form a continuous closed chain as the continuous surface extends from the first support structure <NUM> to the third support structure <NUM>, back to the first support structure <NUM>, and so on. <FIG> also illustrates a second interior-surface portion <NUM> (also illustrated by a reference line in <FIG>) of the first support structure <NUM> that is continuous with an interior-surface portion <NUM> of the third support structure <NUM>. The interior-surface portions <NUM> and <NUM> form a continuous closed chain as the continuous surface extends from the first support structure <NUM> to the third support structure <NUM>, back to the first support structure <NUM>, and so on.

Similar to the explanation of the relationship between the support structures <NUM> and <NUM>, the continuous surface of <NUM> and <NUM> and of <NUM> and <NUM> smoothly transitions from one support structure <NUM> to another support structure <NUM>. The smooth transition minimizes corners or other wall junctions that might otherwise absorb more of a force. That is, this continuous and smooth transition between support structures helps to reduce the likelihood that a compression force will be focused at fewer locations and to allow the compression force to be more evenly distributed throughout the entire system of support structures.

A system of support structures may be built out even further, and <FIG> illustrates another aspect in which additional rows <NUM> and <NUM> of support structures have been added to the system <NUM>. (It should be noted that the break lines on the edges of the walls illustrate that the system might be expanded out further with additional support structures adding to the illustrated matrix. ) In addition, <FIG> illustrates a cross-sectional view showing a relationship between some of the support structures, and illustrating that continuous surfaces may transition from one support structure to another, similar to the manner described in <FIG>, <FIG>. Consistent with one aspect of this disclosure, <FIG> illustrates that a support structure may have continuous surfaces with at least six other support structures. For example, in <FIG> the support structure <NUM> includes an end-to-end, staggered arrangement with the support structures <NUM>, <NUM>, <NUM>, and <NUM>, and in <FIG> the support structure <NUM> includes a side-by-side relationship with the support structures <NUM> and <NUM>. It should be noted that the term "stacked" may refer to an end-to-end arrangement, and in <FIG>, the support structures <NUM>, <NUM>, and <NUM> are illustrated on the drawing page as stacked on, and supported by, the support structures <NUM> and <NUM>. In other aspects, the orientation of the entire system might be rotated clockwise or counterclockwise when integrated into another article, such as a footwear sole, in which case the support structures might still be stacked in a sense of being end-to-end. For example, the support structure <NUM> and the support structure <NUM> are end-to-end with one another, and are laterally staggered (e.g., laterally being opposite to the longitudinal orientations of axes).

<FIG> illustrates other structural aspects of the system of support structures. For example, some support structures in different rows are coaxial - in other words, the reference axis of a first support structure is aligned with the reference axis of a second support structure along a common axis. For example, the reference axis of the support structure <NUM> and the reference axis of the support structure <NUM> are aligned along a common axis <NUM>. These coaxial support structures form columns of spaced apart, coaxial support structures (e.g., they are spaced apart by the staggered, interleaving rows of support structures). For instance, the support structure <NUM> is spaced apart from the support structure <NUM> by the staggered, interleaving support structure <NUM>, and reference lines 640A and 640B are provided in <FIG> to delineate an example column <NUM>. Support structures arranged in columns may also be referred to as "axially aligned," which describes two or more support structures that are aligned longitudinally (e.g., along the longitudinal orientation of the axis), sequentially (not concentrically) along a common axis, such that the axes of the axially aligned support structures are substantially coaxial.

As explained in other portions of this disclosure, the exterior surface of the support structures <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> might include a minimal surface. For example, the exterior surfaces the support structures <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> might include a catenoid or helicoid. In addition, the exterior surfaces might be defined by the equation E1. Among other things, as explained above a minimal-surface geometry may help distribute a load more evenly throughout the entire system <NUM>. In addition, the structure of the individual support structures contributes to each structures ability to connect with adjacent structures in a manner that minimizes high pressure or higher load bearing points.

In an additional aspect, a system of support structures is built out across various portions of a footwear sole. For example, the system <NUM> of <FIG> may be extrapolated out from the medial side to the lateral side and from the heel region to the forefoot region to form at least a portion of the sole structure <NUM> of <FIG>. In addition, the system <NUM> might be extrapolated out and only selectively positioned in different parts of a footwear sole. For example, the extrapolated system might be selectively positioned in the forefoot, the midfoot, the heel, the lateral side, the medial side, any portion of the foregoing, and any combination thereof.

A support structure or a system of support structures may have various elements and operations in the context of a footwear sole. For example, in <FIG> the footwear sole <NUM> includes a ground-contacting outsole having two or more ground-contacting surfaces (when the outsole is at rest on a ground surface) positioned in a reference plane <NUM>. In one aspect of the present disclosure, and according to the claimed invention, the reference axis of one or more support structures included in the sole (e.g., reference axis <NUM> of support structure <NUM>) is inclined towards the heel region <NUM>. In other words, the support structure <NUM> includes a superior end <NUM> and an inferior end <NUM>, and the superior end <NUM> is positioned closer to the heel region <NUM> than the inferior end <NUM>. In addition, the superior end is farther from the outsole than the inferior end <NUM>. As such, in <FIG>, the reference axis <NUM> intersects the reference plane <NUM> at an angle <NUM> in a range of about <NUM> degrees to about <NUM> degrees. In a further aspect, the reference axis intersects the reference plane <NUM> at an angle <NUM> of <NUM> degrees. In other aspects of the disclosure, the angle <NUM> may be smaller or larger than this range. For example, the angle <NUM> may be perpendicular to the reference plane <NUM>, or the axis may incline towards the forefoot. The angular orientation of the support structures relative to the ground-contacting surface may, in some aspects, provide an alignment with a direction of a ground force that contributes to an amount of cushioning and responsiveness.

In an aspect of this disclosure, independent support structures, and a system as a whole might compress in various manners when a load is applied. For example, in some aspects, the walls of each support structure fold, bend, or collapse, and this change in state by the walls absorbs at least part of the load (i.e., provides some load attenuation). In addition, the arrangement of the support structures into a system might contribute to the function of the system as a whole. For example, the arrangement of the support structures into a system of continuous surfaces might contribute to a more gradual, even, and smooth, structure-by-structure collapse as a force is transferred from one part of the system to another. Stated in another way, when a ground force is applied to a first support structure in the system (e.g., foot strike when running), a connected second support structure becomes primed for a gradual collapse, since the continuous surface between the first and second support structures transfers some of the initial force from the first support structure to the second support structure. This continuous surface, and the resulting gradual and relatively linear transfer of force, creates a domino effect from one support structure to the next, which might result in a more even collapse across the system as a whole, as compared with other cell-based or lattice-based systems. In this sense a system of support structures is at least partially a metamaterial, such that the impact-attenuation functionality is derived from characteristics other than the underlying material (e.g., EVA or TPU).

Furthermore, the characteristics of the underlying material may also contribute to the impact-attenuation functionality, and this is described in more detail below. For example, the walls themselves may compress, such that the walls reduce in size under load from a first thickness to a smaller second thickness, to provide additional load attenuation. This aspect of the disclosure in which sole functionality is derived from both the configuration of the support structure(s) and the underlying material might be different from some other footwear soles in which a greater amount of the sole functionality, such as cushioning, is derived from the underlying material (e.g., solid foamed midsoles). By configuring the support structures in a manner that also contributes to sole functionality, such as with even load distribution at least partially attributable to wall configuration, an aspect of this disclosure having the matrix of support structures spaced apart provides a lighter sole as compared with a solid foam midsole.

Various previous portions of this disclosure describe aspects of the support structures and the systems of support structures that contribute to cushioning functionality in a footwear sole while a force is applied. This cushioning functionality is at least partially related to the configuration or shape of the support structures, and some additional aspects of this disclosure are related to methods and materials for making a system of support structures. For example, various different manufacturing techniques and materials may be used, and some techniques and materials may provide confer different traits and qualities to the manufactured support structure.

In one aspect of the present disclosure, a system of support structures is manufactured using a 3D additive-manufacturing technique. In some instances, 3D additive-manufacturing techniques might be better suited than some other manufacturing techniques, such as injection molding or casting, for manufacturing articles having certain geometries. For example, it might be more difficult to construct a system of support structures (e.g., <FIG> and <FIG>) using injection molding than executing a 3D additive-manufacturing process. Various 3D additive-manufacturing techniques might be used to construct a system of support structures. For example, in one instance a system of support structures might be constructed using selective laser sintering (SLS) or stereolithography (SLA). In another aspect, a system of support structures might be manufactured using a multi-jet fusion technique. Each of these techniques might be optimized based on the material being used, geometry and wall thickness of the part, and target traits for the part, such as by tuning the initial temperature of the machine or material bed and the method and delivery of energy used to bind the base material. For example, when executing a multi-jet fusion technology, each of the steps might be adjusted based on a base material, including the temperature of the material bed and base material, fusing-ink type, fusing-ink temperature, type of energy or heat applied, amount of energy of heat applied, number of fusing-ink passes, speed of fusing-ink pass, and the like.

In one aspect of the disclosure, a system of support structures is manufactured by a 3D additive-manufacturing technique with a base material, and the base material includes a rebound-resilience material property that contributes to the functionality of the system of support structures in a footwear sole. For instance, in one aspect of the present disclosure, the support structures are constructed of a base material having high rebound and being highly resilient. High rebound may be defined as a rebound value of at least a <NUM>%. And in other aspects, the rebound percentage is higher, and may be at least <NUM>%. In a further aspect still, the rebound percentage may be at least <NUM>%. Rebound percentage may be tested using various techniques, such as by using a Schob pendulum or other type of tup or ram. Furthermore, the rebound resilience property of a material might relate to footwear-sole performance in various ways. For example, as described above, the configuration of the individual support structures and the system of support structures contributes to the cushioning functionality and the rebound resilience of the base material might contribute to the energy-return functionality. In other words, the configuration of the individual support structures and the system of support structures might at least partially determine the rate and force at which the sole compresses, and the rebound resilience might at least partially determine the recovery of the sole as the force is withdrawn or removed (e.g., when a foot is pulled or lifted off the ground).

The system of support structures may be constructed of various materials having a rebound resilience that contributes to the energy-return functionality. For example, in one aspect, the system of support structures is constructed of a thermoplastic polyurethane (TPU) having a rebound percentage of at least <NUM>%. In another aspect, the TPU has a rebound percentage of at least <NUM>%. And in a further aspect, the TPU has a rebound percentage of at least <NUM>%. As explained above, a system of support structures might be manufactured using a multi-jet fusion technique, and in one aspect of this disclosure, the technique is tailored to the TPU base material. For example, various steps in the multi-jet fusion technique are tailored to the TPU, including the initial temperature of the base material or material bed before fusing, the fusing-ink type, fusing-ink temperature, type of energy or heat applied, amount of energy of heat applied, number of fusing-ink passes, speed of fusing-ink pass, or any combination thereof.

In a further aspect of this disclosure, the support structures may be tuned across the various zones of the footwear sole to achieve an amount of cushioning and responsiveness. For example, the support structures in the sole <NUM> might include a consistent wall thickness, height, and angular orientation across all parts of the sole. In another aspect, each of these elements may be varied independently, collectively, and in any combination across different zones or regions of the footwear sole. For example, the wall thickness of a support structure may gradually change from one region of a sole to another region of a sole. In one illustrative aspect, a heel region of a sole includes support structures having a wall thickness of about <NUM>; a forefoot region includes support structures having a wall thickness of about <NUM>; and the support structures therebetween gradually increase in wall thickness from <NUM> to <NUM>. This is just one example of how support structure features may vary across a sole. In other instances, a heel region might include support structures with thicker walls, relative to the wall thickness of support structures in the forefoot. Likewise, a medial side might include support structures with different characteristics than a lateral side. Various other qualities may also be tuned across a system of support structures, such as the matrix structure, material, and addition of another material to fill in gaps between support structures and/or the hollow cavities among the support structures.

In another aspect support-structure dimensions may be tuned based on various factors. For example, a wall thicknesses may be increased in one or more regions of a sole for wearers that create greater force when contacting a ground surface, due to body weight, activity, running form, and the like. In another example, wall thickness may be tuned to either complement or correct a wearer's running gait, stride, foot strike (e.g., degree of pronation). As such, in accordance with an aspect of this disclosure, a sole having a system of support structures may be customized for a particular wearer based on shoe size, body weight, activity type, movement biomechanics, desired level of cushion, desired level of responsiveness, or any combination thereof. Aspects of this disclosure are particularly well suited for customization based on the ability to implement changes in a footwear sole that are humanly perceptible (based at least on subjective feedback) by making relatively small changes to the support-structure dimensions. For example, testing shows that some users wearing footwear, which has a sole constructed using the support structures described in this disclosure, can subjectively detect as small as a <NUM> change in support-structure wall thickness (e.g., change in the feel of the cushion or of the responsiveness). As used herein, the term "movement biomechanics" describes the quantitative and qualitative categorization of the plurality of positions of a wearer's body at each stage of a movement, including running, walking, and jumping. In addition to tuning the individual support structures, the overall configuration of a midsole may be tuned according to the above described factors. For instance, a heel region may be thicker than other regions of the midsole. In other aspects, a lateral and/or medial peripheral portion may be thicker than more centrally located zones.

<FIG>, <FIG>, and <FIG> each depict different sole structures in accordance with aspects of this disclosure. In one aspect, various programming techniques may be utilized to create a sole structure, such as those depicted in <FIG>, <FIG>, and <FIG>. For example, the computer-aided design applications sold under the trademarks Rhinoceros® or Grasshopper®, or other visual programming tools or languages, may be used, in which case an explicit definition might be created to define the minimal surface of the support-structure exterior surface. (The Rhinoceros and Grasshopper computer-aided design applications are available from, and the Rhinoceros and Grasshopper trademarks are the property of, TLM, Inc. , doing business as Robert McNeel & Associates of Seattle, WA. ) That is, an explicit Grasshopper definition may be created that can be used to create a support structure having a minimal-surface equation, such as E1. Using that Grasshopper definition, various other parameters might be specified, such as wall thickness, sole perimeter shape, sole thickness, sole size, sole foot-bed topography, and sole outsole topography. With the parameters, the Grasshopper definition can conform the support structures to the defined surfaces and populate the space or envelope therebetween. In a further aspect, the explicit definition is customizable based on various factors, such as by adjusting wall thickness, support-structure height, axis orientation, and the like.

<FIG> include a sole <NUM> having a system of support structures (e.g., <NUM> and <NUM>), and at least some of the support structures include features similar to those described with respect to the support structure <NUM> of <FIG>. For example, the support structures constructing the sole <NUM> may include tubular bodies having inwardly curving walls. In another aspect, the exterior surfaces of the inwardly curving walls may be defined by a minimal-surface equation, such as E1. In a further aspect, a ground-contacting outsole of the sole <NUM> includes two or more surfaces positioned in a reference plane <NUM>, and the support structures may include a reference axis <NUM> and <NUM> that is angled relative to the reference plane. The sole <NUM> may include a system of support structures similar to the system <NUM> described with respect to <FIG>. For example, continuous surfaces may transition from one support structure to adjacent support structures in a manner that might contribute to even distribution of force load and load attenuation. For the sake of brevity, all of the features of the support structures described with respect to <FIG> are not reiterated here, but it is understood that the support structures and system of support structures of the sole <NUM> may include all of those features.

Furthermore, as an alternative to the system <NUM>, the sole <NUM> may include support structures <NUM> and <NUM> having respective axis that are not parallel with one another and that are skew (relative to one another), but that have a similar angle with respect to the reference plane <NUM>. The orientation of the axis is another characteristic that may be adjusted, customized, or tuned based on a particular wearer. In an additional aspect of the disclosure, a first region of the sole <NUM> may include support structures with axis in a first orientation; a second region of the sole <NUM> may include support structures with axis in a second orientation that is different from the first orientation; and the axis orientation of support structures between the first and second regions may gradually change from the first orientation to the second orientation.

In a further aspect, the sole <NUM> includes a heel strap <NUM> that is coupled to the sole <NUM> and that extends around the back of the upper <NUM>. The heel strap <NUM> may be integrally formed (e.g., 3D printed, molded, cast, etc.) with the sole <NUM> or may be affixed after the sole <NUM> is formed, such as by using an adhesive. Among other things, the strap may provide additional stability, fit, durability, and the like.

<FIG>- includes a sole <NUM> having a system of support structures (e.g., <NUM> and <NUM>), and at least some of the support structures include features similar to those described with respect to the support structure <NUM> of <FIG>. For example, the support structures constructing the sole <NUM> may include tubular bodies having inwardly curving walls. In another aspect, the exterior surfaces of the inwardly curving walls may be defined by a minimal-surface equation, such as E1. In a further aspect, a ground-contacting outsole of the sole <NUM> includes two or more surfaces positioned in a reference plane <NUM>, and the support structures may include a reference axis <NUM> and <NUM> that is angled relative to the reference plane. The sole <NUM> may include a system of support structures similar to the system <NUM> described with respect to <FIG>. For example, continuous surfaces may transition from one support structure to adjacent support structures in a manner that might contribute even distribution force load and load attenuation. For the sake of brevity, all of the features of the support structures described with respect to <FIG> are not reiterated here, but it is understood that the support structures and system of support structures of the sole <NUM> may include all of those features.

Similar to the sole <NUM>, the sole <NUM> may include support structures <NUM> and <NUM> having respective axis that are not parallel with one another and that are skew (relative to one another), but that have a similar angle with respect to the reference plane <NUM>. In another aspect of the disclosure, the heights of some support structures (e.g., <NUM>) may be larger than other support structures. For example, in the sole <NUM>, support structures around the periphery edge of the sole <NUM> that transition from the midfoot region to the heel region are taller than other support structures in the sole <NUM>. Visually in <FIG>, these taller support structures have the appearance of being drawn upward or stretched relative to other support structures in the sole. Among other things, these taller peripheral regions of the sole <NUM> may contribute to lateral stability. In addition, these regions may provide an anchor surface for attaching the upper <NUM> to the sole <NUM> (e.g., in the biteline region using an adhesive or other bonding agent). Furthermore, by gradually increasing the support-structure height, as opposed to simply stacking additional support structures, the integrity of the matrix may be maintained in a manner that contributes to even distribution of force load.

<FIG> include a sole <NUM> having a system of support structures (e.g., <NUM> and 1022A-C and 1040A-B), and at least some of the support structures include the features described with respect to the support structure <NUM> of <FIG>. For example, the support structures constructing the sole <NUM> include tubular bodies having inwardly curving walls. In another aspect, the exterior surfaces of the inwardly curving walls may be defined by a minimal-surface equation, such as E1. In a further aspect, a ground-contacting outsole of the sole <NUM> includes two or more surfaces positioned in a reference plane <NUM>, and the support structures may include a reference axis <NUM> and <NUM> that is angled relative to the reference plane. The sole <NUM> may include a system of support structures similar to the system <NUM> described with respect to <FIG>. For example, continuous surfaces may transition from one support structure to adjacent support structures in a manner that might contribute even distribution force load and load attenuation. For the sake of brevity, all of the features of the support structures described with respect to <FIG> are not reiterated here, but it is understood that the support structures and system of support structures of the sole <NUM> may include all of those features.

The sole also includes a footbed surface <NUM> and an outsole surface <NUM>. In an aspect of the disclosure, the system of support structures of the sole <NUM> generally transitions from a first region (e.g., the heel region) to a second region (e.g., the midfoot region or the forefoot region). In the first region, the system of support structures are arranged into staggered rows of support structures (e.g., <FIG>), and some of the support structures in different rows are coaxial - in other words, the reference axis of a first support structure is aligned with the reference axis of a second support structure along a common axis. These coaxial support structures form columns of spaced apart, coaxial support structures (e.g., they are spaced apart by the staggered, interleaving rows of support structures), spanning the distance between the footbed surface <NUM> and the outsole surface <NUM>. For example, in <FIG>, the heel region of the sole <NUM> includes one or more columns of three support structures, such as the three support structures 1022A, 1022B, and 1022C (also referred to herein as a "three-stack arrangement), having respective axes aligned along a common axis. In addition, the sole <NUM> transitions from the columns of three support structures in the heel region of the sole <NUM>, to a single support structure (e.g., <NUM>) in the forefoot spanning the distance between the footbed surface <NUM> and the outsole surface <NUM>. Support structures arranged in columns may also be referred to as "axially aligned," which describes two or more support structures that are aligned longitudinally (e.g., along the longitudinal orientation of the axis), sequentially (not concentrically) along a common axis, such that the axes of the axially aligned support structures are substantially coaxial. Although only support structures along the lateral side are identified in <FIG>, the three-stack arrangement continues in adjacent rows as the system moves from the lateral side of the sole to the medial side of the sole. Similarly, a row of single support structures aligned with the support structure <NUM> extends from the lateral side to the medial side.

As illustrated by <FIG>, the system of support structures gradually transitions from the three-stack arrangement in the heel region (e.g., column of three support structures) to the single support structure in the forefoot. For example, the sole <NUM> includes a two-stack arrangement with structures 1040A and 1040B in a midfoot region (e.g., structures 1040A and 1040B are aligned in a column) and between the three-stack arrangement and the single support structure <NUM>. As such, as the sole <NUM> transitions from the heel region to the midfoot region to the forefoot region, the sole <NUM> transitions from a three-stack arrangement to a two-stack arrangement to a single support structure.

Each of the three support structures 1022A-C in the heel region, the two support structures 1040A-B in the midfoot, and the single support structure <NUM> in the forefoot includes respective dimensions, such as height, diameter, and wall thickness. The gradual transition from a three stack to a two stack to a single support structure may include a constant set of respective dimensions across all support structures. Or, in another embodiment, the respective dimensions may gradually change as the system of structures transitions from the three stack down to the single support structure, in order to tune the support structure to achieve a functionality or performance in a particular portion of the sole structure <NUM>. For example, in <FIG>, the height of the single support structure <NUM> is larger than the individual heights of each of the support structures 1022A-C. In addition, the height of support structures positioned between the three-stack arrangement and the single support structure may be smaller than the single support structure <NUM> and larger than the individual height of the support structures in the three stack. In another aspect, the wall thickness of the support structures may transition from a thicker wall in the heel region (e.g., <NUM> to <NUM>) to thinner walls in the forefoot region (e.g., <NUM> to <NUM>), or from thinner walls in the heel region (e.g., <NUM> to <NUM>) to thicker walls in the forefoot region (e.g., <NUM> to <NUM>).

For illustrative purposes, <FIG> depict illustrations of a footwear article <NUM> including a sole <NUM>, which is similar to the sole <NUM>. For example, the sole <NUM> includes a system of support structures that transitions from a three-stack arrangement (e.g., 1122A, 1122B, and 1122C) in the heel region down to a single support structure <NUM> in the forefoot. As indicated above, each of the support structures might include similar dimensions, such as height, diameter, and wall thickness. Or in an alternative embodiment, these dimensions might gradually change from one portion of the sole <NUM> to another portion.

As described in other portions of this disclosure, the soles <NUM> and <NUM> provide cushioning and energy return and are lighter weight than some soles constructed in accordance with some traditional technologies (e.g., solid foam soles). Because the support structures (e.g., <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>) contribute to the cushioning and functionality, less base material is used, as compared to systems that rely more on the material properties of the base foam material. In addition, the configuration of the support structures (e.g., minimal surface) allows for a force load (e.g., ground contact upon foot strike when running) to be more evenly spread throughout the system, providing a consistent cushion throughout the initial phase of the applied force load. Furthermore, the support structures of the soles <NUM> and <NUM> are more durable, and less susceptible to breakage, tearing, or rupture (as compared with other types of support structures, such as struts), since the force load is applied evenly throughout the walls of the support structures and load points are minimized.

Soles constructed in accordance with aspects of this disclosure have been shown to provide a load attenuation that is different from other soles, and as used herein, "load attenuation" refers to act of reducing a force. For example, referring to <FIG> a line graph is depicted showing test results that depict sole deflection on the horizontal axis relative to force on the vertical axis. The deflection range is divided into an initial compression zone <NUM>, a transition zone <NUM>, and a final compression zone <NUM>.

In general, the data is collected and measured by using a load-application device to actively apply a force to a pre-determined value. For example, in one aspect data might be collected by dropping a <NUM> mass onto a sample and measuring "peak G" and "energy loss" (%). The <NUM> mass might take the form of a <NUM> diameter flat tup or ram that impacts one or more zones of a footwear article at <NUM>/s. Generally, a lower peak G value suggests a softer cushioning, and a higher value indicates firmer cushioning. A difference in peak G values between two samples (e.g., two different sole structures) greater than <NUM> is often considered to be a meaningful difference (outside the variance of the machine. ) Moreover, tests often suggest that a difference in peak G values greater than <NUM> for a heel impact translates to a subjective assessment by a wearer of a "Just Noticeable Difference" (JND) between the footwear samples. Energy loss is a measure of responsiveness, and the lower the energy loss the more responsive the cushioning. A difference in energy loss greater than <NUM>% often considered to be a meaningful difference between two samples.

The graph of <FIG> illustrates that about <NUM> N is applied in order to create about <NUM> of deflection, and about <NUM> N is applied in order to achieve about <NUM> of deflection. On average, up until about <NUM> of deflection, the sole deflects about <NUM> for every additional <NUM> N of force load, and this is describes the initial compression zone <NUM>. However, once the sole reaches about <NUM> of deflection, less amount of force load is required to deflect the sole an additional <NUM> (i.e., from <NUM> to <NUM>), and according to the graph, this quantity is less than <NUM> N. This threshold amount of deflection reflects a tipping point <NUM>, at which point the sole structure deflects more easily (with less force required), before the end of the force application, and this describes the transition zone <NUM>. The deflection action of the sole finishes in the final compression zone <NUM> similarly to the initial compression zone <NUM>. <FIG> could depict a single load-attenuation cycle or could represent average values for a single footwear sole structure that is subjected to cycle testing. In one aspect, cycle testing includes repeatedly dropping the tup or ram onto the subject midsole at a frequency correlated to a wearer's footstrike cadence when engaging in a particular activity, such as running.

A few interpretations could be applied to the graph of <FIG> to describe the features of the tested sole structure. For example, one feature illustrated by the graph of <FIG> is that the first two-thirds of sole deflection (i.e., from zero to <NUM>) occurs relatively linearly, suggesting a smooth and consistent compression under load. A second feature illustrated by the graph of <FIG> is that the tipping point, which may simulate or represent a "bottoming out," occurs near the end of the force cycle, and this later-phase tipping point helps to reduce the likelihood that more of the load would be transferred to the wearer's body. In other words, if too much deflection occurs earlier in the load cycle, then the sole has less ability to continue compressing as more force is applied, and this additional force would be transferred to the wearer. Another feature is illustrated by the final compression zone <NUM>, which might suggest that the support-structure walls themselves continue to compress (e.g., compress from a thicker wall thickness to a thinner wall thickness), even after the support structures themselves might have folded or buckled, and this additional compression provides additional cushioning functionality.

In a further aspect, once the sole structure has reached the end of the final compression zone <NUM>, the rebound resilience of the material of the sole structure contributes to the rate at which the sole structure transforms or "springs" back to the resting state, when no load is applied. For example, if a sole is constructed of a less resilient material with a lower bounce percentage, then the deflection might remain much higher after the final compression zone <NUM>, until a much larger amount of the load had been removed.

Some aspects of this disclosure have been described with respect to the examples provided by <FIG>. Additional aspects of the disclosure will now be described that may be related subject matter included in one or more claims of this application, or one or more related applications, but the claims are not limited to only the subject matter described in the below portions of this description. These additional aspects may include features illustrated by <FIG>, features not illustrated by <FIG>, and any combination thereof. When describing these additional aspects, reference may be made to elements depicted by <FIG> for illustrative purposes.

As such, one aspect of the present disclosure includes a support structure for a footwear sole, and examples of a support structure include, but are not limited to, each of the items identified by reference numerals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>-<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. A support structure might be included in a footwear sole or in a system of support structures, or might exist as a separate component, such as prior to be incorporated into a footwear sole. The support structure includes a tubular body including a wall that at least partially encloses a hollow cavity and that extends circumferentially around the hollow cavity. In addition, the tubular body comprising a first end and a second end that are spaced apart from one another in an axial direction. The wall curves inward as the wall extends between the first end and the second end. Furthermore, the wall includes an exterior surface facing away from the hollow cavity, the exterior surface being concave as it extends from the first end and the second end. The wall also includes an interior surface facing towards the hollow cavity, the interior surface being convex as it extends from the first end to the second end. As explained in other parts of this disclosure, the configuration of the support structure might contribute to a more even force distribution, as compared with a structure that has more joints, edges, or corners.

Another aspect of the present disclosure includes a support-structure arrangement for a footwear sole. It should be noted that the term "system" is also used in this disclosure to refer to a support-structure arrangement. The support-structure arrangement includes at least a first support structure and at least a second support structure. In other words, the arrangement might include two support structures and might include more than two support structures. For example, the support structures <NUM> and <NUM> might make up a support-structure arrangement. Likewise, the support structures <NUM> and <NUM> might make up a support-structure arrangement. In addition, the support structures <NUM>, <NUM>, and <NUM> might make up a support-structure arrangement. Furthermore, the system <NUM> or the system <NUM> might make up a support-structure arrangement. These are merely examples. In one aspect of a support-structure arrangement, each of the support structures includes a tubular body including a wall that at least partially encloses a hollow cavity and that extends circumferentially around the hollow cavity. In addition, the tubular body of each support structure includes a first end and a second end that are spaced apart in an axial direction, and the wall of each support structure curves inward as the wall extends between the first end and the second end. The wall includes an exterior surface facing away from the hollow cavity and an interior surface facing towards the hollow cavity. In one aspect, the first support structure and the second support structure are arranged end-to-end. For example, the support structure <NUM> is end-to-end, and axially offset from, the support structure <NUM>. Moreover, a first portion of the exterior surface of the first support structure is continuous with a portion of the interior surface of the second support structure. As explained in other parts of this disclosure, the continuous, gradual, and smooth transition from one support structure to another might contribute to a more even force distribution within the system.

An additional aspect of the disclosure is directed to a footwear sole having a ground-contacting outsole coupled to an impact-attenuation midsole. The ground-contacting outsole has a ground-contacting surface that faces away from the impact-attenuation midsole and that is positioned in a reference plane. The footwear sole also includes a support structure having a tubular body including a wall that at least partially encloses a hollow cavity and that extends circumferentially around a reference axis. The reference axis intersects the reference plane at an angle in a range of about <NUM> degrees to about <NUM> degrees. The tubular body includes a first end and a second end that are spaced apart in an axial direction. In addition, the wall curves inward towards the reference axis as the wall extends between the first end and the second end.

Subject matter set forth in this disclosure, and covered by at least some of the claims, may take various forms, such as a cushioning structure for a midsole, a cushioning system for a midsole, a midsole for a footwear article, a footwear article, any combination thereof, and one or more methods of making each of these aspects or making any combination thereof. Other aspects include a method of tuning a cushioning structure for a midsole, as well as a method of tuning a cushioning system for a midsole.

Claim 1:
A footwear sole (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising: a ground-contacting outsole coupled to an impact-attenuation midsole, the ground contacting outsole having a ground-contacting surface that faces away from the impact-attenuation midsole and that is positioned in a reference plane (<NUM>, <NUM>, <NUM>, <NUM>); and a support structure (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, 1022A, 1022B, 1022C, 1040A, 1040B, <NUM>, 1122A, 1122B, 1122C, 1140A, 1140B) having: a tubular body (<NUM>) including a wall (<NUM>, <NUM>, <NUM>) that at least partially encloses a hollow cavity (<NUM>, <NUM>, <NUM>) and that extends circumferentially around a reference axis (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the reference axis (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) intersecting the reference plane (<NUM>, <NUM>, <NUM>, <NUM>) at an angle (<NUM>) in a range of <NUM> degrees to <NUM> degrees; the tubular body (<NUM>) comprising a first end (<NUM>, <NUM>, <NUM>) and a second end (<NUM>, <NUM>, <NUM>) that are spaced apart from one another in an axial direction; and the wall (<NUM>, <NUM>, <NUM>) curving inward towards the reference axis (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) as the wall (<NUM>, <NUM>, <NUM>) extends between the first end (<NUM>, <NUM>, <NUM>) and the second end (<NUM>, <NUM>, <NUM>).