CUSHION FOR ARTICLE OF FOOTWEAR

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63/725,491, filed on Nov. 26, 2024. The disclosure of this prior application is considered part of the disclosure of this application and is hereby incorporated by reference in its entirety.

FIELD

The present disclosure relates generally to an article of footwear, and more particularly, to a cushion for an article of footwear.

BACKGROUND

This section provides background information related to the present disclosure and is not necessarily prior art.

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

Sole structures generally include a layered arrangement extending between a ground surface and the upper. For example, a sole structure may include a midsole and an outsole. The midsole is generally disposed between the outsole and the upper and provides cushioning for the foot. The midsole may include a pressurized fluid-filled chamber that compresses resiliently under an applied load to cushion the foot by attenuating ground-reaction forces. The outsole provides abrasion-resistance and traction with the ground surface and may be formed from rubber or other materials that impart durability and wear-resistance, as well as enhance traction with the ground surface.

While known sole structures adequately provide cushioning and support during wear, such sole structures generally provide a uniform level of cushioning and support over wide areas of the sole structure. Accordingly, conventional sole structures are not able to be tuned such that specific regions of the sole structure provide targeted cushioning and responsiveness.

DRAWINGS

The drawings described herein are for illustrative purposes only of selected configurations and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of an article of footwear incorporating a sole structure in accordance with the principles of the present disclosure, the sole structure incorporating fluid-filled chambers located between opposing portions of an outsole;

FIG. 2 is a medial side view of the article of footwear of FIG. 1;

FIG. 3 is a lateral side view the article of footwear of FIG. 1;

FIG. 4 is a top exploded view of the sole structure of FIG. 1;

FIG. 5 is a bottom exploded view of the sole structure of FIG. 1;

FIG. 6; is a top view of a cushion for use in the sole structure of FIG. 1;

FIG. 7 is a side view of the cushion of FIG. 6;

FIG. 8 is a top view of a cushion for use in the sole structure of FIG. 1;

FIG. 9 is a side view of the cushion of FIG. 8;

FIG. 10 is a bottom view of the sole structure of FIG. 1 with an outsole removed to show elements of a midsole and a cushion assembly;

FIG. 11 is a top view of a cushion for use in the sole structure of FIG. 1;

FIG. 12 is a side view of the cushion of FIG. 11;

FIG. 13 is a top view of a cushion for use in the sole structure of FIG. 1;

FIG. 14 is a side view of the cushion of FIG. 13;

FIG. 15 is a top view of a cushion for use in the sole structure of FIG. 1; and

FIG. 16 is a side view of the cushion of FIG. 15.

Corresponding reference numerals indicate corresponding parts throughout the drawings.

DETAILED DESCRIPTION

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

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

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

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

In one configuration, a cushion for an article of footwear includes a first barrier element having a columnar body extending between a first end and a second end and a second barrier element attached to the first barrier element at a peripheral seam disposed at the second end of the first barrier element and cooperating with the first barrier element to define an interior void, the second barrier element having an arcuate surface extending in a direction away from the first barrier element and away from the peripheral seam.

The cushion may include one or more of the following optional features. For example, the arcuate surface may define a convex surface facing away from the first barrier element. Additionally or alternatively, the first barrier element may include a circular cross-sectional shape.

In one configuration, the first barrier element may define a first depression at the first end. The first depression may be defined by a first portion of the first barrier element extending toward the second barrier element. The second barrier element may define a second depression opposing the first depression of the first barrier element, the second depression defined by a second portion of the second barrier element extending toward the first barrier element. In this configuration, the first portion of the first barrier element and the second portion of the second barrier element may be attached to one another.

The first barrier element may be attached to the second barrier element at a weld. The weld may be centrally located within an outer perimeter of the columnar body.

A sole structure may incorporate the cushion of Claim 1.

In another configuration, a cushion for an article of footwear includes a first barrier element having a columnar body extending between a first end and a second end and a second barrier element attached to the first barrier element at a peripheral seam disposed at the second end of the first barrier element and cooperating with the first barrier element to define an interior void, the second barrier element being joined to the first barrier element at a weld located within a perimeter of the peripheral seam.

The cushion may include one or more of the following optional features. For example, the second barrier element may define a convex surface facing away from the first barrier element and away from the peripheral seam. Additionally or alternatively, the first barrier element may include a circular cross-sectional shape.

In one configuration, the first barrier element may define a first depression at the first end. The first depression may be defined by a first portion of the first barrier element extending toward the second barrier element. The second barrier element may define a second depression opposing the first depression of the first barrier element, the second depression defined by a second portion of the second barrier element extending toward the first barrier element. In this configuration, the first portion of the first barrier element and the second portion of the second barrier element may be attached to one another at the weld.

The weld may be circular. Additionally or alternatively, the weld may be centrally located within an outer perimeter of the columnar body.

A sole structure may incorporate the cushion.

The details of one or more implementations of the disclosure are set forth in the accompanying drawings and the description below. Other aspects, features, and advantages will be apparent from the description, the drawings, and the claims.

Conventional articles of footwear often include sole structures incorporating fluid-filled chambers. Such sole structures often include a single, fluid-filled chamber that is sized for the particular article of footwear and extends over a majority of a forefoot region of the sole structure and/or a heel region of the sole structure. As such, performance of the sole structure in these regions is limited to the performance characteristics of the single, large fluid-filled chamber. Manufacturing such chambers is often expensive, as only one or two chambers can be manufactured at a time and multiple molds are required to produce the chambers for various sizes of footwear.

The present disclosure relates to incorporating multiple fluid-filled chambers in a sole structure of an article of footwear to maximize performance of the sole structure as well as performance of an article of footwear in which the sole structure is installed while also reducing the costs associated with manufacturing the fluid-filled chambers.

Use of multiple fluid-filled chambers can allow a sole structure to adjust its shape and stiffness according to the terrain and the load, enhancing traction, shock absorption, and energy efficiency. For example, a sole structure incorporating multiple fluid-filled chambers that are independent from one another can flatten or curve to conform to uneven surfaces or stiffen or soften to respond to different impacts or speeds. Incorporating multiple fluid-filled chambers into a sole structure can also provide redundancy and resilience in case of damage or puncture, as the sole structure can still function with some fluid-filled chambers intact or partially deflated. Furthermore, these chambers can be used in different articles of footwear of various sizes, offering versatility in footwear design and manufacturing. Finally, many fluid-filled chambers can be manufactured in a single mold, which can streamline production and reduce costs.

As will be described below, the multiple fluid-filled chambers are used in conjunction with a plate or a plate-like moderator that supports the chambers relative to an upper. The plate or plate-like moderator may be a portion of an outsole or a midsole of the sole structure and includes a channel that bifurcates the plate or plate-like moderator into two segments each attached to at least one fluid-filled chamber. The segments can flex and move relative to one another and, as such, further enhance the ability of the sole structure to flex and move during wear. Further, because each segment is attached to at least one fluid-filled chamber, the fluid-filled chambers are permitted to flex and move relative to one another along with the segments. Use of the multiple fluid-filled chambers in conjunction with the plate or plate-like moderator segments provides the sole structure with a unique cushioning experience that may be tailored by adjusting the number, size, and/or shape of the individual fluid-filled chambers, the locations of the fluid-filled chambers on the segments, the size and/or length of the channel defining the segments, and/or the stiffness of one or more of the segments. The foregoing parameters may be tailored to a particular activity or intended use to allow the sole structure to optimally perform during wear.

With reference to FIG. 1, an article of footwear 10 includes a sole structure 12 and an upper 14. The sole structure 12 is attached to the upper 14 and includes a midsole 16, an outsole 18, and cushion assembly 20. The footwear 10 and, thus, the sole structure 12, may further include an anterior end 22 associated with a forward-most point of the footwear 10, and a posterior end 24 corresponding to a rearward-most point of the footwear 10. A longitudinal axis A₁₀ of the footwear 10 extends along a length of the footwear 10 from the anterior end 22 to the posterior end 24 substantially parallel to a ground surface. As used herein, a longitudinal direction refers to the direction extending from the anterior end 22 to the posterior end 24, while a lateral direction refers to the direction transverse to the longitudinal direction and extending substantially perpendicular to the longitudinal direction.

The longitudinal axis A₁₀ may extend along a center of the article of footwear 10 between the anterior end 22 and the posterior end 24. Accordingly, as shown in FIG. 2, the longitudinal axis A₁₀ may define a medial side 26 of the article of footwear 10. The medial side 26 extends from the anterior end 22 to the posterior end 24.

With continued reference to FIG. 2, the article of footwear 10 may be divided into one or more regions. The regions may include a forefoot region 28, a mid-foot region 30, and a heel region 32. The forefoot region 28 may be subdivided into a toe portion 28_T corresponding with phalanges and a ball portion 28_B associated with metatarsal bones of a foot. The mid-foot region 30 may correspond with an arch area of the foot, and the heel region 32 may correspond with rear portions of the foot, including a calcaneus bone.

As shown in FIG. 3, the longitudinal axis A₁₀ may likewise define a lateral side 34 of the article of footwear 10. As with the medial side 26, the lateral side 34 extends from the anterior end 22 to the posterior end 24.

As described above, the sole structure 12 includes the midsole 16, the outsole 18, and the cushion assembly 20 disposed between the midsole 16 and the outsole 18. The midsole 16 extends from the anterior end 22 to the posterior end 24 and between the medial side 26 and the lateral side 34. As shown in FIGS. 4 and 5, the midsole 16 includes a top surface 36 opposing the upper 14 and a bottom surface 38 disposed on an opposite side of the midsole 16 then the top surface 36. The top surface 36 includes a recess 40 defined by a flange 42 extending around a perimeter of the midsole 16. The recess 40 may cooperate with the upper 14 and an insole (not shown) received within the upper 14 to define a footbed of the article of footwear 10. The flange 42 extends substantially uninterrupted around a perimeter of the midsole 16 from the medial side 26 to the lateral side 34. While the flange 42 may extend substantially uninterrupted around a perimeter of the midsole 16, the flange 42 may include an opening 44 at the anterior end 22 to allow a portion of the outsole 18 to extend up and over a portion of the midsole 16 at the anterior end 22.

The bottom surface 38 may include a first portion 46 and a second portion 48 that are spaced apart from one another by a channel 50. The first portion 46 extends along a length of the midsole 16 from the anterior end 22 to the posterior end 24 and is disposed proximate to and extends along the medial side 26 of the midsole 16. The second portion 48 likewise extends from the anterior end 22 to the posterior end 24 but extends along the lateral side 34 of the midsole 16. The channel 50 separates the first portion 46 and the second portion 48 and extends generally along the longitudinal access A₁₀ of the article of footwear 10 and, as such, extends from the forefoot region 28, through the mid-foot region 30, to the heel region 32. The channel 50 is elongate and has a generally arcuate shape. The channel 50 may be formed into a material of the midsole 16 such that the channel 50 terminates before reaching the top surface 36. Accordingly, the channel 50 may form a recess in the midsole 16 at the bottom surface 38. Alternatively, the channel 50 may be formed through a thickness of the midsole 16 and may extend from the top surface 36 to the bottom surface 38. Finally, the channel 50 includes a terminal end 52 located in the forefoot region 28. The terminal end 52 is located proximate to a junction of the first portion 46 and the second portion 48 located in the forefoot region 28 and proximate to the anterior end 22. The bottom surface 38 additionally includes a recess 54 located in the heel region 32 and proximate to the medial side 26 and the first portion 46. A projection 56 is located between the recess 54 and the posterior end 24 of the midsole 16 and extends in a direction away from the upper 14 to a greater extent than any other portion of the midsole 16 located in the heel region 32. The projection 56 may serve as a stabilizer adjacent to the cushion assembly 20 and may receive a portion of the outsole 18 to define a ground-engaging surface of the sole structure 12.

In one configuration, the midsole 16 is formed from a resilient polymeric material such as foam. Example resilient polymeric materials for the midsole 16 are provided below in the Materials section.

With continued reference to FIGS. 4 and 5, the outsole 18 is shown as extending from the anterior end 22 to the posterior end 24 and between the medial side 26 and the lateral side 34. The outsole 18 may include a first portion 58, a second portion 60, and a channel 62 extending between and separating the first portion 58 and the second portion 60. The first portion 58 is aligned with the first portion 46 of the midsole 16 and, as such, extends along the medial side 26. Likewise, the second portion 60 is aligned with the second portion 48 of the midsole 16 and extends along the lateral side 34. The channel 62 is aligned with the channel 50 of the midsole 16 and extends generally from the forefoot region 28 to the mid-foot region 30. As such, the channel 50 of the midsole 16 is exposed at a ground-engaging surface of the outsole 18 by the channel 62 of the outsole 18. As with the channel 50, the channel 62 is elongate and includes a substantially arcuate shape. The channel 62 includes a terminal end 64 located within the forefoot region 28 and proximate to the anterior end 22. As with the terminal end 52 of the channel 50, the terminal end 64 of the channel 62 is located proximate to a junction of the first portion 58 of the outsole 18 and the second portion 60 of the outsole 18. As with the junction of the first portion 46 of the midsole 16 and the second portion 48 of the midsole 16, the junction of the first portion 58 of the outsole 18 and the second portion 60 of the outsole 18 is located within the forefoot region 28 proximate to the anterior end 22.

The first portion 58 extends from the anterior end 22 from the junction of the first portion 58 and the second portion 60 to a distal end 66 located proximate to the mid-foot region 30. The first portion 58 includes a substantially arcuate shape from the anterior end 22 to the distal end 66. Specifically, the first portion 58 defines a substantially concave surface 68 opposing the midsole 16 and a substantially convex surface 70 disposed on an opposite side of the outsole 18 then the concave surface 68.

The second portion 60 includes a concave surface 72 opposing the midsole 16 and a convex surface 74 disposed on an opposite side of the second portion 60 then the concave surface 72. As shown in FIG. 5, the convex surface 74 extends from the forefoot region 28 proximate to the anterior end 22 to a substantially flat or planar region 76. The flat region 76 extends from the mid-foot region 30 to the heel region 32 and is located closer to the midsole 16 then the convex surface 74 of the second portion 60. The flat region 76 includes a substantially arcuate outer perimeter edge 78 that defines an overall shape of the flat region 76 within the heel region 32. The perimeter edge 78 defines a first projection 80, a second projection 82, a third projection 84, and a fourth projection 86. As shown in FIG. 5, the second projection 82 is located between the first projection 80 and the third projection 84 along the lateral side 34. The fourth projection 86 extends in a direction away from the first projection 80, the second projection 82, and the third projection 84 and in a direction from the lateral side 34 toward the medial side 26. As shown, each of the first projection 80, the second projection 82, the third projection 84, and the fourth projection 86 includes a substantially arcuate outer surface defined by the perimeter edge 78. As will be described in greater detail below, the shapes of the projections 80, 82, 84, 86 are positioned relative to and receive the cushion assembly 20 such that arcuate outer surfaces of the cushion assembly 20 are aligned with respective arcuate surfaces of the first projection 80, the second projection 82, the third projection 84, and the fourth projection 86.

The outsole 18 additionally includes a recess 88 defined by the perimeter edge 78 and located generally between the first projection 80 and the fourth projection 86 within the heel region 32. In one configuration, the midsole 16 may be visible at a ground-engaging surface of the sole structure 12 within the recess 88.

The outsole 18 may be formed from a material that provides the sole structure 12 with abrasion resistance and traction. For example, the outsole 18 may be formed from rubber. Regardless of the material forming the outsole 18, the outsole 18 includes a greater rigidity than the midsole 16. Providing the outsole 18 with a greater rigidity than the midsole 16 allows the outsole 18 to form a ground-engaging surface 90 of the sole structure 12 and, also, allows the outsole 18 to act as a moderator plate between the midsole 16 and the cushion assembly 20.

The outsole 18 forms a portion of the ground-engaging surface 90 in the forefoot region 28 and the mid-foot region 30. The outsole 18 additionally extends from the mid-foot region 30 in a direction toward the midsole 16 within the heel region 32. In so doing, the flat region 76 of the outsole 18 engages the midsole 16 within the heel region 32 and is spaced apart and separated from a ground surface during use of the article of footwear 10. Specifically, the flat region 76 is spaced apart and separated from a ground surface by the cushion assembly 20. The flat region 76 disposed between the midsole 16 and the cushion assembly 20 within the heel region 32 acts as a moderator plate between the midsole 16 and the cushion assembly 20. Because the outsole 18 includes a higher rigidity than that of the midsole 16, the flat region 76 of the outsole 18 serves to distribute point loads received from the cushion assembly 20 across the flat region 76 of the outsole 18, thereby preventing such point loads from being experienced by a wearer of the article of footwear 10.

As shown in FIGS. 4 and 5, the first portion 58, the second portion 60, and the flat region 76 are integrally formed with one another. As such, the outsole 18 extends continuously and uninterrupted from the anterior end 22 to the posterior end 24. Providing the outsole 18 with a unitary construction allows the outsole 18 to be easily attached to the midsole 16 in a single step. Attaching the outsole 18 to the midsole 16 in a single step reduces manufacturing complexity and, thus, reduces the overall cost and complexity associated with assembling the article of footwear 10.

The outsole 18 additionally includes a third portion 92 located in the heel region 32 and forming a portion of the ground-engaging surface 90. The third portion 92 is spaced apart and separated from the first portion 58 and the second portion 60 of the outsole 18 such that a gap extends between the third portion 92 and each of the first portion 58 and the second portion 60 proximate to the ground-engaging surface 90 in a direction substantially parallel to the longitudinal axis A₁₀. As shown, the third portion 92 of the outsole 18 includes a plurality of circular depressions 96 that define respective concave surfaces 98 that oppose the cushion assembly 20 and receive respective fluid-filled chambers 100 of the cushion assembly 20.

As with the first portion 58, the second portion 60, and the flat region 76 of the outsole 18, the third portion 92 of the outsole 18 may be formed from a material that provides the sole structure 12 with abrasion resistance and traction. For example, the third portion 92 of the outsole 18 may be formed from rubber. The material forming the third portion 92 may be the same as or different from the material forming the first portion 58, the second portion 60, and the flat region 76 of the outsole 18. For example, the third portion 92 may be formed from a translucent or transparent rubber material to allow the cushion assembly 20 to be visible at the ground-engaging surface 90 through the third portion 92 of the outsole 18. Alternatively, the third portion 92 may be formed from an opaque material that does not allow the cushion assembly 20 to be visible at the ground-engaging surface 90.

With continued reference to FIGS. 4 and 5, the fluid-filled chambers 100 of the cushion assembly 20 are shown as being discreet elements such that each fluid-filled chamber 100 is spaced apart and separated from an adjacent fluid-filled chamber 100. Accordingly, each of the fluid-filled chambers 100 may be visible around an entire perimeter of the fluid-filled chamber 100 or, alternatively, at least eighty (80) percent of the perimeter of each fluid-filled chamber 100 is visible when installed in the sole structure 12. The fluid-filled chambers 100 will be described and shown hereinafter as being separate air cushions that are free to react independently when subjected to an applied load.

With reference to FIGS. 6 and 7, each of the fluid-filled chambers 100 includes an opposing pair of barrier layers 102, 104. The barrier layers 102, 104 are joined together at a peripheral seam 106, whereby the peripheral seam 106 is formed by joining a material of the barrier layer 102 with a material of the barrier layer 104. In one configuration, the material of the barrier layer 102 and the material of the barrier layer 104 are melded together by applying heat and/or pressure to the material forming the barrier layers 102, 104 at a location of the peripheral seam 106. Once joined, the barrier layers 102, 104 and the peripheral seam 106 cooperate to define an interior void 108 that may be at ambient pressure or, alternatively, may receive a pressurized fluid.

With continued reference to FIGS. 6 and 7, the fluid-filled chamber 100 is shown as being a circular, columnar structure including an interior void 108 that is generally open and free from bonds within the interior void 108. The fluid-filled chamber 100 includes a sidewall 110 defining a diameter of the fluid-filled chamber 100. As shown in FIG. 7, the sidewall 110 extends from the peripheral seam 106 and is substantially straight. While the sidewall 110 is described as being substantially straight, the sidewall 110 may include a slight curvature depending on a pressure of the fluid contained in the interior void 108. Specifically, if the fluid-filled chamber 100 has a relatively low pressure such as, for example, five (5) pounds per square inch (psi), the sidewall 110 will be substantially straight and planar. However, if the interior void 108 is at a higher pressure such as, for example, 15 psi, the sidewall 110 will include a slight curvature.

The fluid-filled chamber 100 additionally includes an arcuate top surface 112 as well as an arcuate side surface 114 extending between and joining the sidewall 110 and the arcuate top surface 112. As shown in FIGS. 6 and 7, the sidewall 110, the arcuate top surface 112, and the arcuate surface 114 are integrally formed with one another and are all formed by a material of the barrier element 102.

The barrier element 104 is joined to the barrier element 102 at the peripheral seam 106 by melding a material of the barrier element 102 with a material of the barrier element 104. Once the materials of the barrier elements 102, 104 are allowed to cool, the barrier elements 102, 104 are joined together at the peripheral seam 106, thereby defining the interior void 108. Once the barrier element 104 is attached to the barrier element 102 at the peripheral seam 106, the interior void 108 may receive a pressurized fluid, thereby exerting a force on the barrier element 102 and the barrier element 104. The force exerted on the barrier elements 102, 104 causes the barrier element 104 to move away from the barrier element 102. In so doing, the barrier element 104 defines an arcuate bottom surface 116. As will be described in greater detail below, when the cushion assembly 20 is attached to the midsole 16 and the outsole 18, the arcuate bottom surface 116 is matingly received by a portion of the outsole 18 to retain and position the individual fluid-filled chambers 100 of the cushion assembly 20 relative to the midsole 16 and the outsole 18.

With particular reference to FIGS. 8 and 9, a fluid-filled chamber 100a is provided and includes a barrier element 102 and a barrier element 104 cooperating to provide the fluid-filled chamber 100a with an interior void 108a. In view of the substantial similarity in structure and function of the components associated with the fluid-filled chamber 100 with respect to the fluid-filled chamber 100a, like reference numerals are used hereinafter and in the drawings to identify like components while like reference numerals containing letter extensions are used to identify those components that have been modified.

As shown in FIGS. 9 and 10, the barrier element 102 is attached to the barrier element 104 at the peripheral seam 106 in a similar fashion as the barrier elements 102, 104 of the fluid-filled chamber 100 described above. The barrier elements 102, 104 of the fluid-filled chamber 100a are additionally attached to one another at a centrally located weld 118. As with the peripheral seam 106, the centrally located weld 118 is formed by applying heat and/or pressure to one or both of the barrier elements 102, 104 to cause a material of the barrier elements 102, 104 to flow and mix together. Once the materials of the barrier elements 102, 104 are mixed together and allowed to cool, the barrier elements 102, 104 are joined together at the weld 118. As shown in FIG. 8, the weld 118 includes a circular shape and is centrally located in the fluid-filled chamber 100a such that the weld 118 is spaced apart and separated from the peripheral seam 106 by the same distance around an outer perimeter of the weld 118.

In forming the weld 118, the barrier element 102 and the barrier element 104 are drawn toward one another and are attached by melding a material of the barrier element 102 and a material of the barrier element 104. As shown in FIG. 9, the weld 118 is located closer to the arcuate top surface 112a of the barrier element 102 than the arcuate bottom surface 116a of the barrier element 104. In so doing, a material of the barrier element 104 is caused to move a greater distance than a material of the barrier element 102 when forming the weld 118. While the weld 118 is described and shown as being disposed closer to the arcuate top surface 112a of the barrier element 102 than the arcuate bottom surface 116a of the barrier element 104, the weld 118 could be centrally located between the arcuate top surface 112a and the arcuate bottom surface 116a or, alternatively, could be located closer to the arcuate bottom surface 116a than the arcuate top surface 112a.

The weld 118 results in the interior void 108a of the fluid-filled chamber 100a being smaller than the interior void 108 of the fluid-filled chamber 100. Further, providing an additional attachment location between the barrier elements 102, 104 provides additional structure to the fluid-filled chamber 100a as compared to the fluid-filled chamber 100. Accordingly, when the fluid-filled chamber 100a is installed in the sole structure 12, the fluid-filled chamber 100a will provide greater stability as compared to the fluid-filled chamber 100. Specifically, the fluid-filled chamber 100a will resist sheer forces and bending to a greater degree than the fluid-filled chamber 100.

As shown in FIG. 9, causing the barrier elements 102, 104 to move toward one another and be joined at the weld 118 results in a depression 120 being located at the arcuate top surface 112a and a depression 122 being located at the arcuate bottom surface 116a. The depression 120 is recessed from the arcuate top surface 112a and the arcuate surface 114 while the depression 122 is recessed from the arcuate bottom surface 116a. Because the weld 118 is described and shown as being disposed closer to the arcuate top surface 112a, the material of the barrier element 104 is required to stretch and move to a greater extent than the material of the barrier element 102. As such, the depression 122 caused by formation of the weld 118 is deeper than the depression 120 and includes a greater volume than the depression 120.

As will be described in greater detail below, providing the sole structure 12 with fluid-filled chambers 100 that are free from welds and fluid-filled chambers 100a that include welds 118 provides the sole structure 12 with customizable and variable cushioning properties at discreet locations of the sole structure 12. Further, adjusting a size of the fluid-filled chambers 100, 110a with or without welds 118 at specific locations of the sole structure 12 further provides the ability to customize and tailor cushioning at discreet locations of the sole structure 12. As such, while the fluid-filled chambers 100, 100a are individual elements having individual characteristics such as size and/or construction (i.e., whether the fluid-filled chamber 100, 100a includes a weld 118) adjacent fluid-filled chambers 100, 100a may cooperate with one another to provide the footwear 10 with a desired cushion response at the sole structure 12. Hereinafter, a fluid-filled chamber 100a having a centrally located weld 118 will be referred to as a “pinned” fluid-filled chamber while a fluid-filled chamber 100 that is free from a centrally located weld 118 will be referred to as a fluid-filled chamber.

With particular reference to FIG. 10, the cushion assembly 20 is shown as including four (4) fluid-filled chambers 100, 100a. Each of the fluid-filled chambers 100, 100a includes an interior void 108, 108a receiving a pressurized fluid. Accordingly, each of the fluid-filled chambers 100, 100a is either a fluid-filled chamber 100 or a pinned fluid-filled chamber 100a. In the configuration shown in FIG. 10, the forward most fluid-filled chamber 100 is disposed proximate to a junction of the mid-foot region 30 and the heel region 32 and is disposed proximate to the lateral side 34 of the sole structure 12. A second fluid-filled chamber 100 is disposed adjacent to and rearward of the first fluid-filled chamber 100 and is located in the heel region 32 proximate to the lateral side 34. A third pinned fluid-filled chamber 100a is located rearward of the second fluid-filled chamber 100 and is likewise located in the heel region 32 proximate to the lateral side 34. The third pinned fluid-filled chamber 100a is located proximate to the posterior end 24 of the sole structure 12 and is disposed further from the anterior end 22 of the sole structure 12 than any other fluid-filled chamber 100 or pinned fluid-filled chamber 100a. Finally, the cushion assembly 20 includes a fourth pinned fluid-filled chamber 100a located in the heel region 32 and disposed proximate to the medial side 26 of the sole structure 12.

As shown in FIG. 10, the forward most fluid-filled chamber 100 includes a smaller size than the adjacent second fluid-filled chamber 100. The rearward most third pinned fluid-filled chamber 100a located at the posterior end 24 of the sole structure 12 includes a larger size than the first fluid-filled chamber 100 but is similarly sized to the second fluid-filled chamber 100 disposed between the forward most fluid-filled chamber 100 and the rearward most pinned fluid-filled chamber 100a. Finally, the fourth pinned fluid-filled chamber 100a located in the heel region 32 proximate to the medial side 26 is larger than each of the other fluid-filled chambers 100 and pinned fluid-filled chamber 100a.

As described, the cushion assembly 20 includes three different sizes of fluid-filled chambers 100 and pinned fluid-filled chambers 100a. In the particular configuration shown in FIG. 10, the fluid-filled chambers 100 and the pinned fluid-filled chamber 100a aligned along the lateral side 34 of the sole structure 12 are positioned such that the forward most fluid-filled chamber 100 is smaller than the rearward fluid-filled chamber 100 and the rearward pinned fluid-filled chamber 100a. As such, a greater degree of cushioning is provided to a wearer at a location closer to the posterior end 24 within the heel region 32 as compared to a location within the heel region 32 that is located closer to the anterior end 22 of the sole structure 12. Finally, the fourth pinned fluid-filled chamber 100a located proximate to the medial side 26 within the heel region 32 is larger than any of the other fluid-filled chambers 100 or pinned fluid-filled chamber 100a and cooperates with the projection 56 of the midsole 16 to provide the medial side 26 of the midsole 16 with cushioning at the heel region 32.

The small, medium, and large fluid-filled chambers 100, 100a may include the same pressure or, alternatively, may include different pressures to further tailor the cushioning response of the sole structure 12. For example, the small, forward most fluid-filled chamber 100 may include an internal pressure of five (5) pounds per square inch (psi) while the medium and large fluid-filled chambers 100 and medium and large pinned fluid-filled chambers 100a include an internal pressure of 15 psi. Use of the terms “small,” “medium,” and “large” to describe the fluid-filled chambers 100 and the pinned, fluid-filled chambers 100a are relative terms meaning that the “small” chambers 100, 100a are smaller than the “medium” and “large” chambers 100, 100a and the “medium” chambers 100, 100a are larger than the “small” chambers 100, 100a but smaller than the “large” chambers 100, 100a.

The individual fluid-filled chambers 100, 100a are received by respective circular depressions 96 of the third portion 92 of the outsole 18 at one end and are attached to the flat region 76 of the outsole 18 at a second end. Specifically, the fluid-filled chambers 100, 100a are received within respective circular depressions 96 of the outsole 18 such that the individual fluid-filled chambers 100, 100a extend between separate portions of the outsole 18 (i.e., between the flat region 76 and the third portion 92). The fluid-filled chambers 100, 100a may have a size and shape that is matingly received by the depressions 96 of the third portion 92 of the outsole 18. Specifically, the fluid-filled chambers 100, 100a may include a bottom surface having the same curvature, size, and depth as the depressions 96 receiving the fluid-filled chambers 100, 100a. Accordingly, the fluid-filled chambers 100, 100a provide discreet, columnar structures that extend from a first end attached to the third portion 92 of the outsole 18 to a second end attached to the flat region 76 of the second portion 60 of the outsole 18. As shown in FIG. 10, the fluid-filled chambers 100, 100a are spaced apart and separated from one another such that a gap exists between adjacent fluid-filled chambers 100, 100a. The gaps disposed between adjacent fluid-filled chambers 100, 100a allow the fluid-filled chambers 100, 100a to splay and collapse under an applied load during use of the article of footwear 10 without contacting an adjacent fluid-filled chamber 100, 100a. Note that while the fluid-filled chambers 100, 100a are described and shown as being disposed between opposing, discrete portions 76, 92 of the outsole 18, the outsole 18 is not shown in FIG. 10 in an effort to clearly show the relative positions of the fluid-filled chambers 100, 100a and the positions of the fluid-filled chambers 100, 100a relative to the midsole 16.

In operation, during a gait cycle, a force may initially be applied to the sole structure 12 during a heel strike. The force may initially be applied to the sole structure 12 at the projection 56 of the midsole 16 and the rearward most pinned fluid-filled chamber 100a. As the heel strike transitions to a forward rolling motion, the force may then be applied to the fluid-filled chamber 100 located proximate to the lateral side 34 and to the pinned fluid-filled chamber 100a located proximate to the medial side 26 before finally being realized by the forward most fluid-filled chamber 100 as the gait cycle continues.

The channels 50, 62 allow the first portion 46 and the second portion 48 of the midsole 16 to move and flex relative to one another. In so doing, the channels 50, 62 likewise allow the first portion 58 and the second portion 60 of the outsole 18 to independently move relative to one another. Because a portion of each fluid-filled chamber 100, 100a is attached to the outsole 18 at the flat region 76, allowing the sole structure 12 to flex and move under an applied load allows the individual fluid-filled chambers 100, 100a to react and deform in a controlled manner, thereby improving the cushioning characteristics of the sole structure 12.

While the sole structure 12 is described and shown as including a cushion assembly 20 having fluid-filled chambers 100, 100a, the sole structure 12 could incorporate fluid-filled chambers having different shapes and configurations.

With particular reference to FIGS. 11 and 12, a fluid-filled chamber 100b is provided and includes a barrier element 102 attached to a barrier element 104 by a peripheral seam 106b to define an interior void 108b. In view of the substantial similarity in structure and function of the components associated with the fluid-filled chamber 100a with respect to the fluid-filled chamber 100b, like reference numerals are used hereinafter and in the drawings to identify like components while like reference numerals containing letter extensions are used to identify those components that have been modified.

As shown in FIGS. 11 and 12, the fluid-filled chamber 100b is a pinned fluid-filled chamber, as the fluid-filled chamber 100b includes a centrally located weld 118 in a similar fashion as the fluid-filled chamber 100a described above. As such, the fluid-filled chamber 100b includes a depression 120 formed in the arcuate top surface 112a and a depression 122 formed in the arcuate bottom surface 116a. The fluid-filled chamber 100b additionally includes a series of channels 124 extending into the sidewall 110b and into the arcuate surface 114b. The channels 124 extend into the interior void 108b and are equally spaced apart from one another around a periphery of the fluid-filled chamber 100b. As shown, the channels 124 each extend from a terminal end 126 disposed within and at the arcuate surface 114b to the peripheral seam 106b. Each channel 124 is defined by a pair of opposing sidewalls 128 that are joined at the terminal end 126. Specifically, the sidewalls 128 are spaced apart and separated from one another across a width of each channel 124 and are substantially parallel to one another. The channels 124 are joined to one another at an arcuate edge 130 located at and defining the terminal end 126.

Each channel 124 includes a concave surface 132 extending from the peripheral seam 106b to the terminal end 126. The concave surface 132 is bounded by the peripheral seam 106b, the sidewalls 128, and the arcuate edge 130. As shown in FIG. 11, a depth of each channel 124 may decrease in a direction extending from the peripheral seam 106b to the arcuate surface 114b. As such, the concave surface 132 may taper in the direction from the peripheral seam 106b to the arcuate surface 114b.

Providing the sidewall 110b with a plurality of evenly spaced channels 124 causes the sidewall 110b to include a series of evenly spaced projections 134 that are each disposed between a pair of adjacent channels 124, as shown in FIGS. 11 and 12. Providing the sidewall 110b with a series of channels 124 and projections 134 increases the structure of the fluid-filled chamber 100b by strengthening the sidewall 110b. The additional structure provided by the channels 124 and projections 134 strengthens the sidewall 110b and, thus, strengthens the fluid-filled chamber 100b. In so doing, the fluid-filled chamber 100b resists bending and sheer forces to a greater extent than the fluid-filled chamber 100a.

With particular reference to FIGS. 13 and 14, a fluid-filled chamber 100c is provided and includes a barrier element 102 cooperating with a barrier element 104 to define an interior void 108c. In view of the substantial similarity in structure and function of the components associated with the fluid-filled chamber 100b with respect to the fluid-filled chamber 100c, like reference numerals are used hereinafter and in the drawings to identify like components while like reference numerals containing letter extensions are used to identify those components that have been modified.

As shown in FIGS. 13 and 14, the fluid-filled chamber 100c includes a series of channels 124c that are equally spaced apart and separated from one another around a periphery of the fluid-filled chamber 100c in a similar fashion as the channels 124 of the fluid-filled chamber 100b. As with the channels 124 of the fluid-filled chamber 100b, the channels 124c of the fluid-filled chamber 100c extend from a terminal end 126c located at the arcuate surface 114c to the peripheral seam 106c. Each channel 124c includes a pair of sidewalls 128c that are spaced apart and separated from one another across a width of the respective channel 124c. A surface 136 extends between the sidewalls 128c and is substantially planar. Specifically, the surface 136 is planar at any location along a length of the channels 124c where the sidewalls 128c oppose one another. However, the surface 136 is arcuate in a direction extending from the peripheral seam 106c to the terminal end 126c. In other words, the surface 136 is arcuate in a direction extending along a length of each channel 124c from the peripheral seam 106c to the terminal end 126c due to the curvature of the barrier element 102 at the arcuate surface 114c. As shown in FIGS. 13 and 14, the terminal end 126c extends between and connects the sidewalls 128c and is substantially straight.

The sidewalls 128c extend from the terminal end 126c to the peripheral seam 106c and are convergent with one another in a direction extending from the terminal end 126c to the peripheral seam 106c. The converging sidewalls 128c cause each channel 124c to taper in a direction from the terminal end 126c to the peripheral seam 106c. As such, the projections 134c disposed between adjacent channels 124c increase in width in a direction extending from the arcuate top surface 112a to the peripheral seam 106c.

As with the fluid-filled chamber 100b, the fluid-filled chamber 100c includes additional structure relative to the fluid-filled chamber 100a due to the inclusion of the channels 124c and the projections 134c in the sidewall 110c. Accordingly, the fluid-filled chamber 100c resists bending and sheer forces to a greater extent than the fluid-filled chamber 100a.

With particular reference to FIGS. 15 and 16, a fluid-filled chamber 100d is provided and includes a barrier element 102 cooperating with a barrier element 104 to define an interior void 108d. In view of the substantial similarity in structure and function of the components associated with the fluid-filled chamber 100b with respect to the fluid-filled chamber 100d, like reference numerals are used hereinafter and in the drawings to identify like components while like reference numerals containing letter extensions are used to identify those components that have been modified.

The fluid-filled chamber 100d includes a series of channels 124d that are spaced apart and separated from one another around a perimeter of the fluid-filled chamber 100d. As with the channels 124b of the fluid-filled chamber 100b, the channels 124d define a series of projections 134d that are spaced apart and separated from one another around a perimeter of the sidewall 110d by an adjacent channel 124d. Each channel 124d extends from a terminal end 126d located at the arcuate surface 114d to the peripheral seam 106d and includes a surface 136d bounded by the terminal end 126d, the peripheral seam 106d, and a pair of opposing sidewalls 128d.

As shown in FIG. 16, each channel 124d includes a serpentine shape such that a terminal end 126d of a respective channel 124d is offset from or misaligned from a junction of the particular channel 124d and the peripheral seam 106d. While the channels 124d each include a substantially serpentine shape, the sidewalls 128d of each channel 124d are substantially equally spaced apart from one another along a length of the channels 124c from the terminal end 126d to the peripheral seam 106d. Accordingly, each channel 124d includes a substantial constant width from the terminal end 126d to the peripheral seam 106d.

As shown in FIG. 15, the surface 136d of each channel 124d is substantially concave. The concave surface 136d includes a substantially constant depth along a length of each channel 124d from the arcuate surface 114d to the peripheral seam 106d. While the arcuate surface 136d is described as including a substantially constant depth, the surface 136d may taper in depth proximate to the terminal end 126d at the arcuate surface 114d.

Providing the fluid-filled chamber 100d with the channels 124d and resulting projections 134d at the sidewall 110d provides the fluid-filled chamber 100d with additional structure. Accordingly, the fluid-filled chamber 100d resists sheer loads and bending to a greater extent than the fluid-filled chamber 100 or 100a.

Materials

Example resilient polymeric materials for the midsole 16 may include those based on foaming or molding one or more polymers, such as one or more elastomers (e.g., thermoplastic elastomers (TPE)). The one or more polymers may include aliphatic polymers, aromatic polymers, or mixtures of both; and may include homopolymers, copolymers (including terpolymers), or mixtures of both.

In some aspects, the one or more polymers may include olefinic homopolymers, olefinic copolymers, or blends thereof. Examples of olefinic polymers include polyethylene, polypropylene, and combinations thereof. In other aspects, the one or more polymers may include one or more ethylene copolymers, such as, ethylene-vinyl acetate (EVA) copolymers, EVOH copolymers, ethylene-ethyl acrylate copolymers, ethylene-unsaturated mono-fatty acid copolymers, and combinations thereof.

In further aspects, the one or more polymers may include one or more polyacrylates, such as polyacrylic acid, esters of polyacrylic acid, polyacrylonitrile, polyacrylic acetate, polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, polymethyl methacrylate, and polyvinyl acetate; including derivatives thereof, copolymers thereof, and any combinations thereof.

In yet further aspects, the one or more polymers may include one or more ionomeric polymers. In these aspects, the ionomeric polymers may include polymers with carboxylic acid functional groups, sulfonic acid functional groups, salts thereof (e.g., sodium, magnesium, potassium, etc.), and/or anhydrides thereof. For instance, the ionomeric polymer(s) may include one or more fatty acid-modified ionomeric polymers, polystyrene sulfonate, ethylene-methacrylic acid copolymers, and combinations thereof.

In further aspects, the one or more polymers may include one or more styrenic block copolymers, such as acrylonitrile butadiene styrene block copolymers, styrene acrylonitrile block copolymers, styrene ethylene butylene styrene block copolymers, styrene ethylene butadiene styrene block copolymers, styrene ethylene propylene styrene block copolymers, styrene butadiene styrene block copolymers, and combinations thereof.

In further aspects, the one or more polymers may include one or more polyamide copolymers (e.g., polyamide-polyether copolymers) and/or one or more polyurethanes (e.g., cross-linked polyurethanes and/or thermoplastic polyurethanes). Examples of suitable polyurethanes include those discussed below with respect to the cushion assembly 20. Alternatively, the one or more polymers may include one or more natural and/or synthetic rubbers, such as butadiene and isoprene.

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

In some embodiments, the foamed polymeric material may be a crosslinked foamed material. In these embodiments, a peroxide-based crosslinking agent such as dicumyl peroxide may be used. Furthermore, the foamed polymeric material may include one or more fillers such as pigments, modified or natural clays, modified or unmodified synthetic clays, talc glass fiber, powdered glass, modified or natural silica, calcium carbonate, mica, paper, wood chips, and the like.

The resilient polymeric material may be formed using a molding process. In one example, when the resilient polymeric material is a molded elastomer, the uncured elastomer (e.g., rubber) may be mixed in a Banbury mixer with an optional filler and a curing package such as a sulfur-based or peroxide-based curing package, calendared, formed into shape, placed in a mold, and vulcanized.

In another example, when the resilient polymeric material is a foamed material, the material may be foamed during a molding process, such as an injection molding process. A thermoplastic polymeric material may be melted in the barrel of an injection molding system and combined with a physical or chemical blowing agent and optionally a crosslinking agent, and then injected into a mold under conditions which activate the blowing agent, forming a molded foam.

Optionally, when the resilient polymeric material is a foamed material, the foamed material may be a compression molded foam. Compression molding may be used to alter the physical properties (e.g., density, stiffness and/or durometer) of a foam, or to alter the physical appearance of the foam (e.g., to fuse two or more pieces of foam, to shape the foam, etc.), or both.

The compression molding process desirably starts by forming one or more foam preforms, such as by injection molding and foaming a polymeric material, by forming foamed particles or beads, by cutting foamed sheet stock, and the like. The compression molded foam may then be made by placing the one or more preforms formed of foamed polymeric material(s) in a compression mold, and applying sufficient pressure to the one or more preforms to compress the one or more preforms in a closed mold. Once the mold is closed, sufficient heat and/or pressure is applied to the one or more preforms in the closed mold for a sufficient duration of time to alter the preform(s) by forming a skin on the outer surface of the compression molded foam, fuse individual foam particles to each other, permanently increase the density of the foam(s), or any combination thereof. Following the heating and/or application of pressure, the mold is opened and the molded foam article is removed from the mold.

As used herein, the term “barrier layer” (e.g., barrier layers 102, 104) encompasses both monolayer and multilayer films. In some embodiments, one or both of the barrier layers 102, 104 are each produced (e.g., thermoformed or blow molded) from a monolayer film (a single layer). In other embodiments, one or both of the barrier layers 102, 104 are each produced (e.g., thermoformed or blow molded) from a multilayer film (multiple sublayers). In either aspect, each layer or sublayer can have a film thickness ranging from about 0.2 micrometers to about 1 millimeter. In further embodiments, the film thickness for each layer or sublayer can range from about 0.5 micrometers to about 500 micrometers. In yet further embodiments, the film thickness for each layer or sublayer can range from about 1 micrometer to about 100 micrometers.

One or both of the barrier layers 102, 104 can independently be transparent, translucent, and/or opaque. As used herein, the term “transparent” for a barrier layer and/or a fluid-filled chamber means that light passes through the barrier layer in substantially straight lines and a viewer can see through the barrier layer. In comparison, for an opaque barrier layer, light does not pass through the barrier layer and one cannot see clearly through the barrier layer at all. A translucent barrier layer falls between a transparent barrier layer and an opaque barrier layer, in that light passes through a translucent layer but some of the light is scattered so that a viewer cannot see clearly through the layer.

The barrier layers 102, 104 can each be produced from an elastomeric material that includes one or more thermoplastic polymers and/or one or more cross-linkable polymers. In an aspect, the elastomeric material can include one or more thermoplastic elastomeric materials, such as one or more thermoplastic polyurethane (TPU) copolymers, one or more ethylene-vinyl alcohol (EVOH) copolymers, and the like.

As used herein, “polyurethane” refers to a copolymer (including oligomers) that contains a urethane group (—N(C═O)O—). These polyurethanes can contain additional groups such as ester, ether, urea, allophanate, biuret, carbodiimide, oxazolidinyl, isocynaurate, uretdione, carbonate, and the like, in addition to urethane groups. In an aspect, one or more of the polyurethanes can be produced by polymerizing one or more isocyanates with one or more polyols to produce copolymer chains having (—N(C═O)O—) linkages.

Examples of suitable isocyanates for producing the polyurethane copolymer chains include diisocyanates, such as aromatic diisocyanates, aliphatic diisocyanates, and combinations thereof. Examples of suitable aromatic diisocyanates include toluene diisocyanate (TDI), TDI adducts with trimethyloylpropane (TMP), methylene diphenyl diisocyanate (MDI), xylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), hydrogenated xylene diisocyanate (HXDI), naphthalene 1,5-diisocyanate (NDI), 1,5-tetrahydronaphthalene diisocyanate, para-phenylene diisocyanate (PPDI), 3,3′-dimethyldipheny1-4, 4′-diisocyanate (DDDI), 4,4′-dibenzyl diisocyanate (DBDI), 4-chloro-1,3-phenylene diisocyanate, and combinations thereof. In some embodiments, the copolymer chains are substantially free of aromatic groups.

In particular aspects, the polyurethane polymer chains are produced from diisocynates including HMDI, TDI, MDI, H12 aliphatics, and combinations thereof. In an aspect, the thermoplastic TPU can include polyester-based TPU, polyether-based TPU, polycaprolactone-based TPU, polycarbonate-based TPU, polysiloxane-based TPU, or combinations thereof.

In another aspect, the polymeric layer can be formed of one or more of the following: EVOH copolymers, poly(vinyl chloride), polyvinylidene polymers and copolymers (e.g., polyvinylidene chloride), polyamides (e.g., amorphous polyamides), amide-based copolymers, acrylonitrile polymers (e.g., acrylonitrile-methyl acrylate copolymers), polyethylene terephthalate, polyether imides, polyacrylic imides, and other polymeric materials known to have relatively low gas transmission rates. Blends of these materials as well as with the TPU copolymers described herein and optionally including combinations of polyimides and crystalline polymers, are also suitable.

The barrier layers 102, 104 may include two or more sublayers (multilayer film) such as shown in Mitchell et al., U.S. Pat. No. 5,713,141 and Mitchell et al., U.S. Pat. No. 5,952,065, the disclosures of which are incorporated by reference in their entirety. In embodiments where the barrier layers 102, 104 include two or more sublayers, examples of suitable multilayer films include microlayer films, such as those disclosed in Bonk et al., U.S. Pat. No. 6,582,786, which is incorporated by reference in its entirety. In further embodiments, barrier layers 102, 104 may each independently include alternating sublayers of one or more TPU copolymer materials and one or more EVOH copolymer materials, where the total number of sublayers in each of the barrier layers 102, 104 includes at least four (4) sublayers, at least ten (10) sublayers, at least twenty (20) sublayers, at least forty (40) sublayers, and/or at least sixty (60) sublayers.

The fluid-filled chambers 100 can be produced from the barrier layers 102, 104 using any suitable technique, such as thermoforming (e.g. vacuum thermoforming), blow molding, extrusion, injection molding, vacuum molding, rotary molding, transfer molding, pressure forming, heat sealing, casting, low-pressure casting, spin casting, reaction injection molding, radio frequency (RF) welding, and the like. In an aspect, the barrier layers 102, 104 can be produced by co-extrusion followed by vacuum thermoforming to produce an inflatable chamber, which can optionally include one or more valves (e.g., one way valves) that allows the chambers 100 to be filled with the fluid (e.g., gas).

The chambers 100 can be provided in a fluid-filled (e.g., as provided in footwear 10) or in an unfilled state. The chambers 100 can be filled to include any suitable fluid, such as a gas or liquid. In an aspect, the gas can include air, nitrogen (N₂), or any other suitable gas. In other aspects, the chambers 100 can alternatively include other media, such as pellets, beads, ground recycled material, and the like (e.g., foamed beads and/or rubber beads). The fluid provided to the chambers 100 can result in the chambers 100 being pressurized. Alternatively, the fluid provided to the chambers 100 can be at atmospheric pressure such that the chambers 100 are not pressurized but, rather, simply contains a volume of fluid at atmospheric pressure.

The fluid-filled chambers 100 desirably have a low gas transmission rate to preserve their retained gas pressure. In some embodiments, the fluid-filled chambers 100 have a gas transmission rate for nitrogen gas that is at least about ten (10) times lower than a nitrogen gas transmission rate for a butyl rubber layer of substantially the same dimensions. In an aspect, fluid-filled chambers 100 have a nitrogen gas transmission rate of 15 cubic-centimeter/square-meter atmosphere·day (cm³/m²·atm·day) or less for an average film thickness of 500 micrometers (based on thicknesses of the barrier layers 102, 104). In further aspects, the transmission rate is 10 cm³/m²·atm·day or less, 5cm³/m²·atm·day or less, or 1cm³/m²·atm·day or less.

The upper 14 may be formed from one or more materials that are stitched or adhesively bonded together to define an interior void. Suitable materials of the upper 14 may include, but are not limited to, textiles, foam, leather, and synthetic leather. The example upper 14 may be formed from a combination of one or more substantially inelastic or non-stretchable materials and one or more substantially elastic or stretchable materials disposed in different regions of the upper 14 to facilitate movement of the article of footwear 10 between the tightened state and the loosened state. The one or more elastic materials may include any combination of one or more elastic fabrics such as, without limitation, spandex, elastane, rubber or neoprene. The one or more inelastic materials may include any combination of one or more of thermoplastic polyurethanes, nylon, leather, vinyl, or another material/fabric that does not impart properties of elasticity.

In some examples, the outsole 18 is a composite material manufactured using fiber sheets or textiles, including pre-impregnated (i.e., “prepreg”) fiber sheets or textiles. Alternatively or additionally, the outsole 18 may be manufactured by strands formed from multiple filaments of one or more types of fiber (e.g., fiber tows) by affixing the fiber tows to a substrate or to each other to produce an outsole having the strands of fibers arranged predominately at predetermined angles or in predetermined positions. When using strands of fibers, the types of fibers included in the strand can include synthetic polymer fibers which can be melted and re-solidified to consolidate the other fibers present in the strand and, optionally, other components such as stitching thread or a substrate or both. Alternatively or additionally, the fibers of the strand and, optionally the other components such as stitching thread or a substrate or both, can be consolidated by applying a resin after affixing the strands of fibers to the substrate and/or to each other.

In some configurations, the outsole 18 may be formed from one or more layers of tows of fibers and/or layers of fibers including at least one of carbon fibers, boron fibers, glass fibers, and polymeric fibers. In a particular configuration, the fibers include carbon fibers, or glass fibers, or a combination of both carbon fibers and glass fibers. The tows of fibers may be affixed to a substrate. The tows of fibers may be affixed by stitching or using an adhesive. Additionally or alternatively, the tows of fibers and/or layers of fibers may be consolidated with a thermoset polymer and/or a thermoplastic polymer. Accordingly, the outsole 18 may have a tensile strength or flexural strength in a transverse direction substantially perpendicular to the longitudinal axis of the article of footwear (i.e., the axis extending from the anterior end 22 to the posterior end 24). The stiffness of the outsole 18 may be selected for a particular wearer based on the wearer's tendon flexibility, calf muscle strength, and/or metatarsophalangeal (MTP) joint flexibility. Moreover, the stiffness of the outsole 18 may also be tailored based upon a running motion of the athlete. In other configurations, the outsole 18 is formed from one or more layers/plies of unidirectional tape. In some examples, each layer in the stack includes a different orientation than the layer disposed underneath. The outsole 18 may be formed from unidirectional tape including at least one of carbon fibers, boron fibers, glass fibers, and polymeric fibers. In some examples, the one or more materials forming the outsole 18 result in the outsole 18 having a Young's modulus of at least 70 gigapascals (GPa).

In some implementations, the outsole 18 includes a substantially uniform thickness T. In some examples, the thickness T of the outsole 18 ranges from about 0.6 millimeters (mm) to about 3.0 mm. In one example, the thickness T of the outsole 18 is substantially equal to one 1.0 mm. In other implementations, the thickness T of the outsole 18 is non-uniform such that the outsole 18 may have a greater thickness T in one region of the sole structure 12 than the thicknesses T in another region.

The foregoing description has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular configuration are generally not limited to that particular configuration, but, where applicable, are interchangeable and can be used in a selected configuration, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.