Patent Application
20210052038
The present invention relates to an article of footwear and, in particular, footwear including an upper with a temperature modulation structure.
Articles of footwear typically include an upper and a sole structure attached to the upper that cooperate to define a foot cavity. Controlling the microclimate of the foot cavity—the temperature and humidity within the foot cavity, including the position of air layers relative to the foot or sock—is important for wearer comfort. High temperature and humidity inside the foot cavity may cause discomfort and/or affect blood flow (straining on the wearer's vascular system). Excessive humidity within the foot cavity, moreover, may promote the growth of microorganisms (fungi and bacteria).
Accordingly, it would be desirable to provide an upper for footwear capable of affecting the microclimate within the foot cavity.
An article of footwear includes a sole structure and an upper attached to the sole structure. The upper is formed from a textile including interlocked strands oriented in a predetermined configuration. The upper further includes a microclimate modulation structure operable to affect the microclimate of the foot cavity. The microclimate modulation structure includes pockets configured to capture heated and/or moist air away from the surface of the foot. The microclimate modulation structure further includes strands possessing high thermal conductivity that selectively positioned within the textile structure. The high thermal conductivity strands are capable of transferring heat at a higher rate than surrounding strands.
Like reference numerals have been used to identify like elements throughout this disclosure.
As described herein with reference to the example embodiment of
In weft knitting, one continuous strand runs crosswise in the fabric, making all of the loops in one course. Weft knitting includes fabrics formed on both circular knitting and flat knitting machines. With circular knitting machines, the fabric is produced in the form of a tube, with the strands running continuously around the fabric. With a flat knitting machine, the fabric is produced in flat form, the threads alternating back and forth across the fabric. In an embodiment, the upper 105 is formed via flat knitting utilizing stitches including, but not limited to, a plain stitch; a rib stitch, a purl stitch; a missed or float stitch (to produce a float of yarn on the fabric's wrong side); and a tuck stitch (to create an open space in the fabric). The resulting textile includes an interior side (the technical back) and an exterior side (the technical face), each layer being formed of the same or varying strands and/or stitches. By way of example, the knit structure may be a single knit/jersey fabric, a double knit/jersey fabric, and/or a plated fabric (with yarns of different properties are disposed on the face and back). In a specific embodiment, the textile is a double knit fabric formed via a flat knitting process.
The strands forming the textile (and thus the upper 105) may be any natural or synthetic strands suitable for their described purpose (to form a knit upper). The term “strand” includes one or more filaments organized into a fiber and/or an ordered assemblage of textile fibers having a high ratio of length to diameter and normally used as a unit (e.g., slivers, roving, single yarns, plies yarns, cords, braids, ropes, etc.). In a preferred embodiment, a strand is a yarn, i.e., a continuous strand of textile fibers, filaments, or material in a form suitable for knitting, weaving, or otherwise intertwining to form a textile fabric. A yarn may include a number of fibers twisted together (spun yarn); a number of filaments laid together without twist (a zero-twist yarn); a number of filaments laid together with a degree of twist; and a single filament with or without twist (a monofilament).
The strands include elastic strands or inelastic strands. An elastic strand is formed of elastomeric material; consequently, by virtue of its composition, the strand possesses the ability to stretch. Accordingly, an elastic strand possesses elasticity and/or recovery, i.e., the ability to stretch/deform under load and recover to immediately after removal of the load. The degree to which fibers, yarn, or cord returns to its original size and shape after deformation indicates how well a fabric recovers. Some specific examples of elastomers are elastic polymers such as elastomeric polyester-polyurethane copolymers. By way of specific example, elastane, a manufactured fiber in which the fiber-forming substance is a long chain synthetic polymer composed of at least 85% of segmented polyurethane, may be utilized.
In contrast, inelastic strands are not formed of elastomeric material; consequently, by virtue of their composition alone, inelastic strands possess substantially no inherent stretch and recover properties. Hard yarns are a type of inelastic strand. Hard yarns include natural and/or synthetic spun staple yarns, natural and/or synthetic continuous filament yarns, and/or combinations thereof. By way of specific example, natural fibers include cellulosic fibers (e.g., cotton, bamboo) and protein fibers (e.g., wool, silk, and soybean). Synthetic fibers include polyester fibers (poly(ethylene terephthalate) fibers and poly(trimethylene terephthalate) fibers), polycaprolactam fibers, poly(hexamethylene adipamide) fibers, acrylic fibers, acetate fibers, rayon fibers, nylon fibers and combinations thereof.
The strands suitable for forming the upper 105 further include heat sensitive strands. Heat sensitive strands include flowable (fusible) strands and softening. Flowable strands are include polymers that possess a melting and/or glass transition point at which the solid polymer liquefies, generating viscous flow (i.e., becomes molten). In an embodiment, the melting and/or glass transition point of the flowable polymer may be approximately 80° C. to about 150° C. (e.g., 85° C.). Examples of flowable strands include thermoplastic materials such as polyurethanes (i.e., thermoplastic polyurethane or TPU), ethylene vinyl acetates, polyamides (e.g., low melt nylons), and polyesters (e.g., low melt polyester). Preferred examples of melting strands include TPU and polyester. As a strand becomes flowable, it surrounds adjacent strands. Upon cooling, the strands form a rigid interconnected structure that strengthens the textile and/or limits the movement of adjacent strands.
Softening strands are polymeric strands that possess a softening point (the temperature at which a material softens beyond some arbitrary softness). Many thermoplastic polymers do not have a defined point that marks the transition from solid to fluid. Instead, they become softer as temperature increases. The softening point is measured via the Vicat method (ISO 306 and ASTM D 1525), or via heat deflection test (HDT) (ISO 75 and ASTM D 648). In an embodiment, the softening point of the strand is from approximately 60° C. to approximately 90° C. When softened, the strands become tacky, adhering to adjacent stands. Once cooled, movement of the textile strands is restricted (i.e., the textile at that location stiffens).
One additional type of heat sensitive strand which may be utilized is a thermosetting strand. Thermosetting strands are generally flexible under ambient conditions, but become irreversibly inflexible upon heating.
The strands may also include heat insensitive strands. Heat insensitive strands are not sensitive to the processing temperatures experienced by the upper (e.g., during formation and/or use). Accordingly, heat insensitive strands possess a softening, glass transition, or melting point value greater than that of any softening or melting strands present in the textile structure and/or greater than the temperature ranges specified above.
It should be understood that a strand may be categorized in a combination of the above categories. For example, a polyester yarn may be both a heat insensitive and an inelastic strand, as defined above.
Referring to
The upper 105 includes a plurality of sections that cooperate to define the foot cavity. A heel section 210 includes heel cup configured to align with and cover the calcaneus area of a human foot. A lateral quarter section 215, disposed forward the heel section 210, is oriented on the lateral shoe side 205B. Similarly, a medial quarter section 220, disposed forward the heel section 210, is oriented on the medial shoe side 205A. A vamp section 225 is disposed forward the quarter sections 215, 225, while a toe cage section 230 is disposed forward the vamp section. The upper 105 may further includes an instep cover section 240 configured to align and span the instep area of the foot and a planum section or footbed 300 (
With this configuration, the heel 210, lateral quarter 215, medial quarter 220, vamp 225, toe cage 230 and planum 300 sections cooperate to form a foot cavity 332 (
The upper 105 may possess a unitary structure (also called a unibody construction) to minimize the number of seams utilized to form the shape of the upper. That is, the upper 105 may be formed as a one-piece template, each template portion being integral with adjacent template portions. Stated yet another way, each section 210, 215, 220, 225, 230, 240, 300 of the upper 105 may include a common strand interconnecting that section with adjacent sections (i.e., the common strand spans both sections). In addition, the connection between adjacent sections may be stitchless and seamless. By stitchless and/or seamless, it is meant that adjacent sections are continuous or integral with each other, including no edges that require joining by stitches, tape, adhesive, welding (fusing), etc.
Referring to
The lateral quarter section 215 is adapted to receive a fastener such as a shoe lace. In an embodiment, the lateral quarter 215 includes a plurality of looped sections 245A, 245B, 245C, 245D disposed at the lateral quarter distal edge (upper edge). As illustrated, the looped sections 245A-245D are linearly spaced, being generally aligned in an array extending longitudinally along the shoe 100. In this manner, each looped section 245A-245D is configured to receive the fastener 120 (the shoe lace), movably capturing the fastener therein. The looped sections 245A-245D, moreover, cooperate with one or more elements disposed on the instep cover 240 to engage the fastener 120 and secure the shoe 100 to the foot of the wearer (described in greater detail, below).
Referring to
The instep cover 240 is configured to span the dorsum portion of the midfoot (i.e., the instep). The instep cover 240 may be formed integrally (stitchlessly and/or seamlessly) with the medial quarter section 220. As best seen in
The instep cover 240 may include one or more narrow, elongated openings or slots 260 operable to permit passage of the fastener 120 therethrough. The instep cover 240 may also include additional openings or windows 285 operable to improve airflow into/out of the upper.
The forefoot region 200A of the upper 105 includes the vamp section 225, which extends forward from the lateral quarter 215 and medial quarter 220 sections, being formed integrally therewith (e.g., stitchlessly and seamlessly). The vamp section 225 defines the throat line 250 within its proximal region and toe cage 230 within its distal region, the toe cage being configured to span the toes of the foot.
The vamp 225, moreover, includes a microclimate modulation structure (also called microclimate moderation structure) operable to affect movement of heat, air, and/or moisture (e.g., vapor) within the foot cavity 332. Thermal comfort is an important factor considered in footwear design. The microclimate of footwear, which contributes to thermal comfort, is influenced by heat and moisture within the foot cavity. Accordingly, moving heat and/or moisture away from the surface of the foot and/or exhausting heat from the foot cavity 332 optimizes the microclimate which, in turn, optimizes the thermal comfort experienced by the user.
The temperature modulation structure includes strands selected to possess predetermined thermal conductivity values positioned at selected locations within the knit construction of the textile. Specifically, the temperature modulation structure 400 includes first, high thermal conductivity strands and second, low thermal conductivity strands. High conductivity strands are strands that transfer heat along its length (axis) and/or width (transverse dimension) at a higher rate than low thermal conductivity strands. In an embodiment, high thermal conductivity strands are strands formed (e.g., entirely formed) of material possessing a thermal conductivity value greater than 0.40 W/m K. By way of example, the strands may be formed of high density polyethylene (HDPE, 0.45-0.52 @23 C) and/or ultra-high molecular weight polyethylene (UWMW-PE, 0.42-0.51 W/m K @23 C).
In a further embodiment, high thermal conductivity strand is a strand that possessing an axial thermal conductivity of at least 5 W/m K (e.g., at least 10 W/m K or at least 20 W/m K). The high thermal conductivity strand may be a multifilament fiber such as a gel-spun fiber. By way of specific example, the high conductivity strand is a gel-spun, multifilament fiber produced from ultra-high molecular weight polyethylene (UHMW-PE), which possesses a thermal conductivity value in the axial direction of 20 W/m K.
The low thermal conductivity strand, in contrast, transfers heat along its length (axis) and/or width (transverse dimension) at a lower rate than that of the high thermal conductivity strand. In an embodiment, the low thermal conductivity strand is formed (e.g., entirely formed) of material possessing a thermal conductivity of no more than 0.40 W/m K. By way of example, the low conductivity strand may be formed of low density polyethylene (LDPE, 0.33 W/m K @23 C), nylon (e.g., nylon 6; nylon 6,6; or nylon 12) (0.23-0.28 W/m K @23° C.), polyester (0.15-0.24 W/m K @23° C.), and/or polypropylene (0.1-0.22 W/m K @23 C).
In another embodiment, the low thermal conductivity strand possesses an axial thermal conductivity (as measured along its axis) that is less than the axial conductivity of the high conductivity strands. By way of example, the low thermal conductivity strands possess an axial thermal conductivity value of less than 5 W/m K when high thermal conductivity strand possesses a thermal conductivity of greater than 5 W/m K; of less than 10 W/m K when high conductivity strand possesses a thermal conductivity of at least 10 W/m K; and/or less than 20 W/m K when high conductivity strand possesses a thermal conductivity of greater than 20 W/m K. Exemplary low thermal conductivity strands include strands formed of polyester staple fibers (axial thermal conductivity: 1.18 W/m K); polyester filament strands (axial thermal conductivity: 1.26 W/m K); nylon fiber strands (axial thermal conductivity: 1.43 W/m K); polypropylene fiber strands (axial thermal conductivity: 1.24 W/m K); cotton strands (axial thermal conductivity: 2.88 W/m K); wool strands (axial thermal conductivity: 0.48 W/m K); silk strands (axial thermal conductivity: 1.49 W/m K); rayon strands (axial thermal conductivity: 1.41-1.89 W/m K); and aramid strands (axial thermal conductivity: 3.05-4.74 W/m K), as well as combinations thereof.
The microclimate modulation structure 400 may further possess a knit construction or structure configured to affect the microclimate of the foot cavity 332 (either independently or in cooperation with the high thermal conductivity strands). Referring to
Each portion 405, 410 of the microclimate modulation structure 400 is independently capable of affecting the movement of heat, air, and/or moisture within the cavity and/or exhausting it from the foot cavity 332. It should be understood, however, that the portions 405, 410 cooperate with each other, working in concert to affect the foot cavity microclimate (i.e., the portions operate independently of each other and cooperatively with each other).
Referring to
The longitudinal 520 and transverse 525 beams define areas of increased height relative to the indentations 515. In an embodiment, the height of the beams 520, 525 and/or the depths of the indentations 515 is approximately two millimeters or more to provide appropriate spacing of the indentation from the interior layer 510 and/or foot/sock surface (discussed in greater detail below). By way of specific example, a combination of jersey and float stitches may be utilized to form the indentations 515 and beams 520, 525.
The knit construction may be configured such that each indentation 515 formed into the outer side 535 of the exterior layer 505 forms a corresponding beam 520, 525 protruding from the inner side 540 of the exterior layer. Similarly, each indentation 515 formed into the inner side 540 of the exterior layer 505 forms a corresponding beam 520, 525 protruding the outer side 535 of the exterior layer (i.e., the topography on the inner side is the negative of the outer side topography). Accordingly, as seen in
Each indentation 515 forms a pocket or chamber (e.g., a polygonal or rectangular shaped pocket) within the exterior layer 505 along its inner, foot-cavity-facing side 540. Each pocket is oriented in spaced relation from the immediate foot surface (or sock surface) and/or the interior layer 510. That is, the longitudinal 520 and/or transverse beams 525 on the inner side 540 act as spacers to maintain a gap between the indentations 515 and the foot (and/or the interior layer 510). With this configuration, the resulting pockets are capable of collecting/capturing heated and/or moist air from the foot cavity 332 (e.g., heat generated by the forefoot portion of the foot) and storing it away from the foot/sock surface, thereby increasing wearer comfort. In operation, heated and/or moist air along the surface of the foot travels upward, away from the foot surface and into the pockets, where it is collected. The moist air may travel through apertures 555 formed into the interior layer 510 and aligned with indentations 515. The depth of the indentation 515 and height of the beams 525 may cooperate to create a pocket spaced approximately two millimeters to five millimeters from the foot or sock surface. Moving heated air two millimeters or more from the foot surface improves the microclimate experienced by the wearer.
The first portion 405 of the microclimate modulation structure 400 may further include exhaust ports 545 (i.e., openings defined in the knit construction) in fluid communication with the foot cavity 332. Referring to
In addition, the exterior layer 505 may include vertical channels or passages 552 in communication with the apertures 555 of the interior layer 510.
With this configuration, movement of fluid (air/vapor) is permitted into and out of the foot cavity 332. For example, heated and/or moist air collected/captured within the cavity 332 (i.e., within each indentation 515) travels into the passages 542, through vertical channel 552, and along transverse channel 547, escaping via the exhaust ports 545, thereby improving the foot cavity microclimate.
The interior layer 510, which is exposed to the foot cavity 332, is a generally planar layer that spans the array of indentations 515 and beams 520, 525 of the vamp 225 (i.e., the waffle pattern). In an embodiment, the layer 510 is generally continuous, and may possess a lower stitch density than that of the exterior layer 505 (e.g., to assist fluid movement therethrough). As noted above, the interior layer 510 may further include apertures 555 disposed at selected locations that permit passage of fluid (air/vapor). By way of example, each aperture 555 may be generally aligned with a corresponding pocket or indentation 515 along the interior side 540 of the exterior layer 505. With this configuration, moist or heated air from the foot cavity 332 passes through the apertures 555 and is directed into the pockets 515 of the exterior layer 505 where it is stored away from the user.
As noted above, the portions 405, 410 of the modulation structure 400 are formed of low thermal conductivity strands and high thermal conductivity strands placed at selected locations within the construction. In an embodiment, the interior layer 510 is formed primarily (e.g., >50%), substantially (e.g., >90%), or completely (100%) of high thermal conductivity strands (with any remainder being low conductivity strands). The exterior layer 505, in contrast, is formed primarily, substantially, or completely of low thermal conductivity strands. Accordingly, the interior layer 510 is a thermal conduction layer, being operable to transfer heat at a higher rate than the exterior layer 505. In an embodiment, the interior layer 510 is formed completely of high thermal conductivity strands and the exterior layer 505 is formed completely of low conductivity strands.
It is believed the above described configuration modulates the comfort of the shoe 100 by affecting the movement of moisture, airflow, and/or heat within the foot cavity 332. In operation, heat and water vapor generated by the foot are released into the foot cavity 332, traveling upward, toward the first portion 405 of the microclimate modulation structure 400. The heat and/or water vapor contacts the interior layer 510, which, being formed of high thermal conductivity strands, conducts heat along its volume (its surface area), spreading the heat over a wide surface area to prevent the formation of hot spots and to disperse the heat. In addition, the interior layer 510 draws water vapor away from the foot via the capillary action of the knit structure. Heat and/or water vapor, furthermore, pass through the apertures 555 of the interior layer 510. Once past the interior layer 110, heat and/or vapor are either received by the indentations 515 of the exterior layer 505, being temporarily stored away from the surface of the foot/sock. Additionally, the heat and/or vapor may be exhausted from the foot cavity 332 via exhaust ports 545.
As noted above, the second portion 410 of the microclimate modulation structure 400 surrounds the first portion 405, extending along the lateral 415 and medial 420 sides of the vamp section 225, terminating proximate the throat line 250 at its rear, and extending forward to the toe cage 230. In an embodiment, the second portion 410 includes a plurality of ribs and channels spaced along the technical face (exterior side) and/or the technical back (interior side) of the upper 105. Specifically, referring to
As with the first portion 405, the second portion 410 includes strands possessing relatively higher and lower thermal conductivity values disposed at selected positions within the construction. For example, the high thermal conductivity strands may be located within the inner layer 610 of the knit structure, or may be located in one or both of the exterior 615 and interior 610 layers of the structure. In an embodiment, the knit construction is configured such that the exterior layer 615 is formed primarily, substantially, or completely of low thermal conductivity strands and the interior layer 610 is formed primarily, substantially, or completely formed of high thermal conductivity strands.
It should be understood, however, that the amount of high thermal conductivity strands present within the second portion 410 of the microclimate modulation structure 410 may be any suitable for its described purpose. In an embodiment, the high thermal conductivity strand 615 forms at least 25% (e.g., at least 30%, at least 40%, at least 50%, etc.) of the second portion 410 (e.g., at least 25% of the strands forming the second portion are high thermal conductivity strands; or at least 25% of the overall strand weight of the second portion is due to the high thermal conductivity strands). In a further embodiment, the high thermal conductivity strands represent no more than 60% of the strands forming the second portion 410 (e.g., the high thermal conductivity strands form 25%-60% of the second portion).
In addition, the knit construction selectively exposes strands forming the interior layer 615 through the exterior layer 610 and, accordingly, the ambient environment. As noted above, each of the exterior 610 and interior 615 layers includes continuous strands forming courses along the crosswise textile direction. The stitches may be selected such that a continuous strand forming the interior layer 615 is exposed at selected locations along the strand length, and vice versa. By way of specific example, selectively placing float stitches within the exterior layer 610 further including ribbing selectively exposes the strand forming the interior layer 610 (technical back, also called the inside loop). With this configuration, the strand possessing high thermal conductivity forming the inner layer (technical back) is selectively exposed, appearing as a transverse bridge between the longitudinal bands of ribbing. Stated another way, and as best seen in
In operation, it is believed multiple independent and/or cooperating mechanisms occur to affect the foot cavity microclimate. Specifically, heat and/or water vapor generated by the foot travels toward the second portion 410. The heat and/or water are either directed along the channels 630, or contact the high thermal conductivity strands. The channels 630 encourage the movement of air, aiding in creating a cooling sensation. In addition, the high thermal conductivity strands transfer heat, spreading it along their lengths such that heat is spread over a wide surface area. The strands of the first portion 405, furthermore, are in communication with the strands of the second portion 410. Accordingly, heat from the first portion is spread across the second portion, and vice versa. Finally, the portions of the high thermal conductivity strand exposed along the exterior layer 610 permits escape of heat absorbed by the high thermal conductivity strand to the ambient environment.
With specific regard to water vapor, hydrophobic, high thermal conductivity strands such as strands formed of UHMW-PE do not absorb water. Accordingly, it is believed that any water vapor present in the cavity contacts the strand, where it is drawn away from the foot cavity 332 via capillary action within the knit structure.
The sole structure 110 comprises a durable, wear-resistant component configured to provide cushioning as the shoe 100 impacts the ground. In certain embodiments, the sole structure 110 may include a midsole and an outsole. In additional embodiments, the sole structure 110 can further include an insole that is disposed between the midsole and the upper 105 when the shoe 100 is assembled. In other embodiments, the sole structure 110 may be a unitary and/or one-piece structure. As can be seen, e.g., in the exploded view of
The sole structure 110 may be formed of a single material or may be formed of a plurality of materials. In example embodiments in which the sole structure includes a midsole and an outsole, the midsole may be formed of one or more materials including, without limitation, ethylene vinyl acetate (EVA), an EVA blended with one or more of an EVA modifier, a polyolefin block copolymer, and a triblock copolymer, and a polyether block amide. The outsole may be formed of one or more materials including, without limitation, elastomers (e.g., thermoplastic polyurethane), siloxanes, natural rubber, and synthetic rubber.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. For example, while most of the example embodiments depicted in the figures show an article of footwear (shoe) configured for a right foot, it is noted that the same or similar features can also be provided for an article of footwear (shoe) configured for a left foot (where such features of the left footed shoe are reflection or “mirror image” symmetrical in relation to the right footed shoe).
While the figures depict the first microclimate modulation structure 400 as being located in the vamp 225 region of the shoe 100 proximate the instep of the upper 105, it should be understood that the first structure may be located at any location suitable for its described purpose.
Within the knit structure, various stitches may be used to provide different sections 210, 215, 220, 225, 230, 240, 300 of the upper 105 with different properties. For example, a first area may be formed of a first stitch configuration, and a second area may be formed of a second stitch configuration that is different from the first stitch configuration to impart varying textures, structures, patterning, and/or other characteristics to the upper member.
The dimensions (e.g., length, width, and depth), spacing, geometric shape and pattern of the indentations 515, the longitudinal beams 520, and/or the transverse beams 525 can vary for different embodiments to provide different aesthetic and/or heat transfer effects for the upper 105.
Stitching may be utilized to connect sections of the upper together. In addition, a thermoplastic film may be utilized to reinforce seams, replace stitching, and/or prevent fraying. For example, seam tape available from Bemis Associates, Inc. (Shirley, Mass.) may be utilized.
Instead of an instep cover 240, the upper 105 may include a conventional tongue including a longitudinally extending member free on its lateral and medial sides.
It is to be understood that terms such as “top”, “bottom”, “front”, “rear”, “side”, “height”, “length”, “width”, “upper”, “lower”, “interior”, “exterior”, “inner”, “outer”, and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration.
Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
The present application is a continuation of U.S. patent application Ser. No. 15/149,596, filed May 9, 2016 and entitled “Footwear Including a Textile Upper”, which claims priority to U.S. Provisional Patent Application Ser. No. 62/158,709, filed May 8, 2015 and entitled “Footwear Including a Textile Upper.” The disclosure of the aforementioned applications are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 62158709 | May 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15149596 | May 2016 | US |
| Child | 16984346 | US |
