FOOTWEAR WITH TRACTION LUGS BONDED TO A MIDSOLE
20220125164 · 2022-04-28
Inventors
Cpc classification
International classification
Abstract
A footwear construction includes a sole assembly having a midsole of a first durometer and a plurality of separate, individually reactive lugs of a second, greater durometer bonded to the midsole. On soft terrain, the individual lugs can remain extended and can engage that terrain to provide grip and traction. On hard terrain, the individual lugs can independently compress into deformation regions of the midsole to enhance traction, so that the midsole also can optionally contact the terrain with portions of the lugs. The sole assembly can include a fabric embedded and encapsulated in the materials of the lugs and the midsole to mechanically bond the lugs to the midsole and impair delamination. The individual lugs can include caps extending into the midsole with voids filled with the midsole material to improve the lug securement. A related method of manufacture also is provided.
Claims
1. A footwear construction comprising: a midsole constructed from a first material having a first durometer, the midsole including a midsole upper surface, a ground facing midsole lower surface, and a plurality of lug recesses, each lug recess defined in the midsole lower surface and bounded by a recess bottom and a recess boundary edge, the midsole including a deformation region above each lug recess; and a plurality of outsole lugs disposed in respective ones of the plurality of lug recesses, each outsole lug constructed from a second material, different from the first material, and having a second durometer greater than the first durometer, the outsole lug projecting outward from the respective recess, the outsole lug including a base plate and a lug body, the lug body including a lug wall that transitions from the base plate downward to a lug ground contacting surface, the base plate including a lug perimeter flange extending laterally outward from the lug wall and including a flange lower surface and a lug flange edge, the lug flange edge being adjacent and facing the recess boundary edge, the base plate including a contact wall that is chemically and physically bonded to the recess bottom, below the deformation region, wherein the outsole lug is operable in a soft traction mode in which the lug extends below the midsole lower surface a first distance between 0.1 mm and 15 mm, and a hard traction mode, in which the lug compresses upward into the deformation region of the midsole so that the outsole lug extends below the midsole lower surface a second distance less than the first distance, and so that at least a portion of the midsole lower surface is a midsole ground contacting surface.
2. The footwear construction of claim 1 comprising: a post extending upward from the base plate into the midsole, the post including a post axis; a cap joined with an upper end of the post, the cap extending outwardly from the post axis so that a void is formed between the cap and the base plate.
3. The footwear construction of claim 2, wherein the first material is disposed in the void and mechanically interlocks with the cap so that the outsole lug is impaired from mechanical removal from the midsole.
4. The footwear construction of claim 3, wherein the cap extends radially outward from the post axis, wherein the cap extends above the lug perimeter flange, wherein the cap is disposed inwardly a distance from the lug perimeter flange.
5. The footwear construction of claim 1 comprising: a fabric embedded and encapsulated in the outsole lug and in the midsole, the fabric being concealed in the outsole lug and the midsole, the fabric providing additional mechanical bonding to secure the outsole lug to the midsole to prevent delamination of the outsole lug from the midsole.
6. The footwear construction of claim 5, wherein the fabric includes an upper surface and a lower surface, wherein the fabric extends within the base plate, with the second material being disposed above the upper surface and below the lower surface.
7. The footwear construction of claim 6, wherein the fabric extends within the recess, wherein the fabric extends adjacent the midsole lower surface without being visible in the midsole lower surface.
8. The footwear construction of claim 1 comprising: a cap joined with the base plate opposite the lug body with a void formed between the cap and the base plate; and a fabric disposed in the void adjacent the cap and extending adjacent the base plate and adjacent the midsole lower surface, wherein the fabric is embedded and encapsulated in the first material of the midsole, wherein the first material of the midsole extends into the void; wherein the fabric and the first material in the void provide additional mechanical bonding to secure the outsole lug to the midsole to prevent delamination of the outsole lug from the midsole.
9. The footwear construction of claim 1 comprising: a fabric including a plurality of adjacent strands with a plurality of interstitial spaces between the adjacent strands, wherein the fabric is joined with the outsole lug so that the second material extends through respective ones of the plurality of interstitial spaces, the second material encapsulating respective ones of the plurality of adjacent strands coextensive with the outsole lug, wherein the fabric is joined with the midsole so that the first material extends through respective ones of the plurality of interstitial spaces, the first material encapsulating respective ones of the plurality of adjacent strands coextensive with the midsole.
10. The footwear construction of claim 9, wherein the fabric is embedded and concealed in the outsole lug and the midsole, and not visible to a viewer of the midsole from a bottom view thereof.
11. A footwear construction comprising: a midsole constructed from a first material having a first durometer, the midsole including a midsole upper surface, a ground facing midsole lower surface, and a plurality of lug recesses, each lug recess defined in the midsole lower surface and bounded by a recess bottom and a recess boundary edge, the midsole including a deformation region above each lug recess; and a plurality of outsole lugs disposed in respective ones of the plurality of lug recesses, each outsole lug constructed from a second material different from the first material and having a second durometer greater than the first durometer, the outsole lug projecting outward from the respective recess, the outsole lug including a base plate and a lug body, the lug body including a lug wall that transitions from the base plate downward to a lug ground contacting surface, the base plate including a lug perimeter flange extending laterally outward from the lug wall and including a flange lower surface and a lug flange edge, the base plate being bonded to the recess bottom, below the deformation region, wherein the outsole lug is operable in a soft traction mode in which the lug extends below the midsole lower surface a first distance and a hard traction mode, in which the lug compresses upward into the deformation region of the midsole so that the outsole lug extends below the midsole lower surface a second distance less than the first distance.
12. The footwear construction of claim 11, wherein the flange lower surface is at least one of below and flush with the midsole lower surface; wherein the lug flange edge is spaced by a gap from the recess boundary edge.
13. The footwear construction of claim 12, comprising: a cap joined with the base plate opposite the lug body, with a void formed between the cap and the base plate, wherein the first material of the midsole extends into and fills the void; wherein the first material in the void provides mechanical bonding to secure the outsole lug to the midsole, whereby delamination of the plurality of outsole lugs from the midsole is impaired.
14. The footwear construction of claim 11, wherein the outsole lug in the soft traction mode extends below the midsole lower surface a first distance of 0.1 mm to 15 mm inclusive, wherein the outsole lug compresses upward into the deformation region of the midsole in the hard traction mode so that the outsole lug extends below the midsole lower surface a second distance less than the first distance, wherein the base plate bends upward in the hard traction mode, with the recess deforming convexly upward.
15. The footwear construction of claim 11, wherein the first durometer is less than 50 Shore D, wherein the second durometer is greater than the first durometer.
16. The footwear construction of claim 11 comprising: a fabric substrate extending through and embedded within the outsole lug and the second material, wherein the fabric substrate extends away from the outsole lug and is embedded within the midsole and the first material, adjacent the midsole lower surface, wherein the fabric substrate is initially embedded in the first and second materials in different molds.
17. A method of making a footwear construction, the method comprising: placing in a mold a plurality of individual and spaced apart outsole lugs, each outsole lug including a base plate facing upward into a mold cavity of the mold and a lug body, the lug body including a lug wall that transitions from the base plate downward to a lug ground contacting surface, the base plate including a contact wall and a lug perimeter flange extending laterally outward from the lug wall and including a flange lower surface and a lug flange edge; introducing into the mold cavity a midsole material that bonds to the contact wall of each of the plurality of lugs; curing the midsole material to form a midsole having a first durometer less than a second durometer of each of the plurality of lugs, the plurality of lugs being commonly joined with the midsole and one another; and removing the midsole with the plurality of lugs joined therewith from the mold.
18. The method of claim 17 comprising: embedding a fabric in each of the plurality of lugs before the placing step, so that each of the plurality of lugs are commonly joined with the fabric.
19. The method of claim 18 comprising: allowing the midsole material to encapsulate the fabric during the introducing step so that the midsole material bonds with the fabric and the plurality of lugs to enhance the securement of the plurality of lugs to the midsole.
20. The method of claim 17 comprising: providing each of the plurality of lugs with a cap that extends upward from the base plate when each lug is in the mold, the cap and base plate forming a void therebetween; flowing the midsole material into the void adjacent the cap and cure, whereby the mechanical bond between the midsole and the plurality of lugs is enhanced, wherein the base plate of each outsole lug is distal from an adjacent base plate of an adjacent outsole lug, so that the midsole joins the base plates in a spaced part relationship upon curing.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DESCRIPTION OF THE CURRENT EMBODIMENTS
[0034] A current embodiment of the footwear is illustrated in
[0035] The use of directional terms should not be interpreted to limit the invention to any specific orientation. Further, as used herein, the term “arch region” (or arch or midfoot) refers generally to the portion of the footwear or sole assembly corresponding to the arch or midfoot of the wearer's foot; the term “forefoot region” (or forefoot) refers generally to the portion of the footwear forward of the arch region corresponding to the forefoot (for example, including the ball and the toes) of a wearer's foot; and the term “heel region” (or heel) refers generally to that portion of the footwear rearward of the arch region corresponding to the heel of the wearer's foot. The forefoot region 12, arch region or mid-foot region 14, and heel region 16 generally are identified in
[0036] With reference to
[0037] The footwear 10 can include a textile upper 17 joined with the sole assembly 20. The upper 17 can be formed from a variety of material elements joined together to cover at least a portion of the wearer's foot. The material elements can be selected based on the intended uses of the article of footwear 10, and can include synthetic textiles, mesh textiles, polymers or leather, for example. The upper 17 can be constructed to improve the rigidity of the sole assembly 20. For example, the upper can be constructed from leather, plastic, canvas or other materials. The upper 17 can include one or more closure elements, including for example shoelaces (not shown). The upper 17 additionally includes an upper opening 19 for receiving the wearer's foot and a lower periphery 13 for attachment to the sole assembly 20.
[0038] A footbed (not shown) can be positioned within the void defined by the upper and can be non-stretchable and lightweight and joined to the upper to provide a void for receipt of the wearer's foot. The footbed can be constructed from a sheet of material, such as foam, EVA, polyurethane (PU), latex, gel or other materials, and by virtue of its compressibility, provide cushioning, and may also conform to the foot in order to provide comfort, support and stability. The lower peripheral allowance or edge of the upper can be stitched, cemented or otherwise fastened to the footbed around the perimeter of the footbed. The sole assembly 20 can be combined with any other type or style of upper construction capable of being suitably joined with it, for example, a Strobel construction. With a Strobel construction, a Strobel board or insole board or insole 18 can be joined with the lower peripheral allowance 13 of the upper to close the void 12 of the upper. The joining of the sole assembly/outsole and the upper can be accomplished using adhesives, cement, injection molding, pour molding or any other technique used to join an upper and sole assembly.
[0039] With reference to
[0040] As shown, the midsole upper surface 30U can be joined to the Strobel board 18 and portions of the lower peripheral allowance 13 of the upper. The attachment can be via cement, adhesives, heat bonding, stitching, or other techniques and structures. The midsole lower surface 30LS can be contoured or flat depending on the footwear application and the intended interaction with an underfoot terrain G, which can be any surface, such as ground, hard terrain like concrete, pavement, rocks, rocky surfaces, hard clay, flooring, etc, and/or soft terrain, like soft ground, sand, soft clay, gravel, grass, tundra, forest floor, field dirt, etc.
[0041] As mentioned above, the midsole can include the midsole sidewalls 30M and 30L. These sidewalls can take on a variety of contours leading from the upper surface to the lower surface. In some cases, the sidewalls can be concave or convex. The midsole 30 can be constructed from a variety of materials, such as ethyl vinyl acetate (EVA), polyurethane (PU), latex, a gel, expanded thermoplastic polyurethane (eTPU), and/or polyether block amides (PEBA), such as plasticizer-free poly(ether-b-amide)s offered under the tradename Pebax® from Arkema of France. The midsole can relatively soft, compliant and elastic. In some cases, the midsole can be constructed from a first material having a first durometer of optionally less than 75 Shore D, less than 60 Shore D, less than 40 Shore D, less than 30 Shore D, less than 25 Shore D, between 25 Shore D and 50 Shore D, inclusive, between 25 Shore D and 40 Shore D, inclusive, or between 20 Shore D and 35 Shore D, inclusive. In some cases, the material can have a tear strength of optionally less than 170 kN/m, less than 150 kN/m, less than 125 kN/m, less than 100 kN/m, less than 75 kN/m, less than 50 kN/m, between 40 and 150 kN/m, inclusive, between 50 and 125 kN/m, inclusive, or between 60 and 100 kN/m.
[0042] The midsole 40 can include the midsole lower surface 30LS, which can also be referred to as a ground facing midsole lower surface. That surface can in come application be relatively flat, with the individual lugs bonded directly to that surface via molding of the midsole material to the individual lugs in a mold as described below. As shown in
[0043] The midsole 30 can include a deformation region DR above each lug recess. This deformation region can be a region that can be highly compressed or simply compressed more than an adjacent region AR of the midsole that is not above an individual lug 41 of the sole assembly. The deformation region can be of a volume sufficient to receive at least a portion of the lug when the lug retracts into the midsole as shown in
[0044] As mentioned above, the sole assembly 20 can include multiple, individual outsole lugs 40 disposed distal and independently from one another on the midsole lower surface 30L and/or in the respective lug recesses 31 as described above. The individual lugs 40 can be arranged as desired, and alternatively in a repeating pattern. The lugs can include one or more geometric shapes. The individual outsole lugs 40 can be constructed from one or more second materials, for example, natural or synthetic rubber, thermoplastic polyurethane elastomers, nylon, polymer blends, wear resistant polymers, elastomers and/or other materials. Other materials, such as fiber-reinforced polymers can be used, which can include epoxy, polyethylene or thermosetting plastic reinforced with carbon, glass and/or aramid fibers for enhanced protection. The second material can have a durometer that is greater than the first durometer of the first material of the midsole.
[0045] As shown in
[0046] The base plate 42 can include a lug perimeter flange 46 extending laterally outward from one or more of the lug walls 44W and including a flange lower surface 46U and a lug flange edge 47. The lug perimeter flange can extend outward laterally from each lug wall 40W by a distance DF that is optionally 0 mm to 5 mm, inclusive, 0.1 mm to 3 mm inclusive, or 0.1 mm to 2 mm inclusive. The base plate, perimeter flange and lug flange edge can each have a base height HB extending between the contact wall 42CW and the flange lower surface 46U. That base height HB can be less than, equal to or greater than the depth of the lug recess HR. Where the base height is less than the depth HR, the lower surface 46U is above the midsole lower surface 30LS. Where the base height is equal to the depth HR, the lower surface 46U is flush with the midsole lower surface 30LS. Where the base height is greater than the depth HR, the lower surface is below the midsole lower surface.
[0047] The base plate 42 and the recess can be oriented so there is a gap G1 around the flange edge 33. For example, the lug flange edge 33 can be adjacent and facing the recess boundary edge 33. Those elements, however, can be separated by a gap G1 between them around the lug and the base plate. Optionally, the gap can be optionally 0 mm to 2 mm, inclusive, 0.1 mm to 2 mm, inclusive, or 0.1 mm to 0.5 mm, inclusive, and can vary around the base plate.
[0048] As mentioned above, the base plate can include a contact wall 42CW that is chemically and physically bonded to the recess bottom, below the deformation region DR. The contact wall 42CW can extend from the respective edges 47 on opposing sides of the base plate 42. The contact wall 42W can be smooth and planar as shown, or can have contours and/or projections extending up from it to enhance the mechanical bonding of the midsole material to it. For example, in an alternative embodiment, shown in
[0049] Returning to the embodiment in
[0050] As shown in
[0051] A method of making the footwear 10 and sole assembly 20 in particular will now be described. In general, the method can include placing in a mold multiple ones of the lugs 40, having the features of the lug 41 shown in
[0052] The individual lugs can be placed in the midsole mold according to their shape and assigned location. For example, different shaped and sized lugs can be placed in different locations depending on their intended function and traction capabilities. The midsole mold can be in the shape of the midsole and generally of a user's foot. The individual outsole lugs can be spaced apart in the configuration shown in
[0053] With all the individual lugs properly placed, the mold cavity can be closed and a midsole material, that is, the first material described above, can be introduced into the cavity, optionally under pressure, or by pour molding or some other means. The midsole material in its fluid form can bond to the contact wall 42CW and the edge 47 in some locations of each of the lugs.
[0054] With the midsole material having filled the mold cavity and engaged each of the individual lugs with spaces therebetween, the midsole material can be cured for a time. This curing allows the midsole material to form the midsole 30. That midsole can have the first durometer less than the second durometer of each of the plurality of lugs, the plurality of lugs being commonly joined with the midsole and one another. After the midsole is cured, the midsole with the lugs joined therewith can be removed from the mold. From there, the sole assembly can be cemented, glued or otherwise joined with the upper 17 as described above.
[0055] A first alternative embodiment of the sole assembly 120 and a particular lug 141 is shown in
[0056] As shown in
[0057] The method of making the sole assembly 110 of this construction is virtually identical to the method of making that of the embodiment above with several exceptions. For example, in the molding of the lugs, each of those lugs can be molded to include a cap that extends upward from the base plate, the cap and base plate forming a void therebetween. When those lugs are placed in the midsole mold cavity, the caps of individual lugs extend upward into the cavity. When the midsole material is introduced, it flows into each of the voids adjacent the caps and cures. In this way, the mechanical bond between the midsole and each of the lugs is enhanced. In this construction, like the one above, the base plate of each outsole lug can be distal from an adjacent base plate of an adjacent outsole lug, so that the midsole joins the base plates in a spaced part relationship upon curing.
[0058] A second alternative embodiment of the sole assembly 220 and a particular lug 241 is shown in
[0059] The fabric 260 as shown can be embedded and encapsulated in the midsole material 230. As shown, the fabric can be joined with the midsole so that the first material or midsole material extends through respective ones of the plurality of interstitial spaces. The midsole material can encapsulate respective ones of the plurality of adjacent strands coextensive with the midsole. The fabric can be embedded and concealed in the midsole, and not visible to a viewer of the midsole from a bottom view thereof. For example, the fabric 260 can extend adjacent the midsole lower surface 230LS, and can be disposed below that surface a sufficient distance DF so that the fabric is not visible in or at the lower surface. Optionally, in some cases where an aesthetic design is desired, that fabric can show though the lower surface so it is visible therein or thereon. The fabric 260 also can be disposed in the void 153 adjacent the cap 150. The fabric can further extend adjacent the base plate 243, and in particular the contact wall 242CW.
[0060] Further, the fabric can extend into the void 253 with the first material of the midsole. As an example, the fabric can extend into the void, inward from the outer perimeter plane P of the cap toward the post axis PA a distance D1, and can be folded or wrinkled near the post 252. The fabric optionally can contact the post or cap in the void. In some cases, the fabric can be located a distance D2 from the post or cap, so that the midsole material engages the cap or post rather than the fabric. This can enhance the connection of the lug to the midsole. The fabric and the first material in the void can provide additional mechanical bonding to secure the outsole lug to the midsole to prevent delamination of the outsole lug from the midsole.
[0061] The method of making the sole assembly 210 of this construction is virtually identical to the method of making that of the embodiments above with several exceptions. For example, in the molding of the lugs, each of those lugs can be molded to include a cap that extends upward from the base plate, the cap and base plate forming a void therebetween. When those lugs are placed in the midsole mold cavity, the caps of individual lugs extend upward into the cavity.
[0062] With the lugs and caps so placed in the mold, the fabric 260 can be placed over the lugs and caps. The fabric can lay against the contact wall 242CW, in the void 253 and on the top 251T of the cap. Optionally, the fabric can be stuffed into the voids 253 of the respective lugs. When the midsole material is introduced, it flows into each of the voids adjacent the caps. In so doing, it can push and urge the fabric farther into the voids the distance D1. The midsole material can also embed within the fabric and can encapsulate the respective strands, projecting through the interstitial spaces. When the midsole material cures, the mechanical bond between the midsole and each of the lugs can be enhanced with the additional cap and fabric bonding.
[0063] A third alternative embodiment of the sole assembly 320 and in particular lug 341 and fabric 360 is shown in
[0064] A fourth alternative embodiment of the sole assembly 420 and a particular lug 441 and fabric 460 is shown in
[0065] The method of making the sole assembly 410 of this construction is virtually identical to the method of making that of the embodiments above with several exceptions. For example, in the molding of the lugs, each of those lugs can be molded with a second material of the lug to include its various features. Before this molding, however, the fabric 460 can be placed in the mold 500 as shown in
[0066] With the outsole lugs molded to the fabric, the lugs and the fabric can be placed in another mold 600 as shown in
[0067] Directional terms, such as “vertical,” “horizontal,” “top,” “bottom,” “upper,” “lower,” “inner,” “inwardly,” “outer” and “outwardly,” are used to assist in describing the invention based on the orientation of the embodiments shown in the illustrations. The use of directional terms should not be interpreted to limit the invention to any specific orientation(s).
[0068] In addition, when a component, part or layer is referred to as being “joined with,” “on,” “engaged with,” “adhered to,” “secured to,” or “coupled to” another component, part or layer, it may be directly joined with, on, engaged with, adhered to, secured to, or coupled to the other component, part or layer, or any number of intervening components, parts or layers may be present. In contrast, when an element is referred to as being “directly joined with,” “directly on,” “directly engaged with,” “directly adhered to,” “directly secured 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 components, layers and parts should be interpreted in a like manner, such as “adjacent” versus “directly adjacent” and similar words. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
[0069] The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. For example, and without limitation, any individual element(s) of the described invention may be replaced by alternative elements that provide substantially similar functionality or otherwise provide adequate operation. This includes, for example, presently known alternative elements, such as those that might be currently known to one skilled in the art, and alternative elements that may be developed in the future, such as those that one skilled in the art might, upon development, recognize as an alternative. Further, the disclosed embodiments include a plurality of features that are described in concert and that might cooperatively provide a collection of benefits. The present invention is not limited to only those embodiments that include all of these features or that provide all of the stated benefits, except to the extent otherwise expressly set forth in the issued claims. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular. Any reference to claim elements as “at least one of X, Y and Z” is meant to include any one of X, Y or Z individually, any combination of X, Y and Z, for example, X, Y, Z; X, Y; X, Z; Y, Z, and/or any other possible combination together or alone of those elements, noting that the same is open ended and can include other elements.