Patent Application
20170340056
The present teachings generally include a sole structure for an article of footwear.
Footwear typically includes a sole structure configured to be located under a wearer's foot to space the foot away from the ground. Sole assemblies in athletic footwear are configured to provide desired cushioning, motion control, and resiliency.
A sole structure for an article of footwear comprises a sole plate that includes a forefoot portion with a foot-facing surface and a ground-facing surface opposite from the foot-facing surface. The sole plate may be a unisole plate, an inner board plate, an outsole plate, a midsole plate, or any combination of an inner board plate, an outsole plate, and a midsole plate. The sole structure further comprises a tension member operatively secured to the ground-facing surface and having a portion configured to move relative to the sole plate during dorsiflexion of the sole structure in a first portion of a flexion range, and interfere with the sole plate during dorsiflexion of the sole structure in a second portion of the flexion range greater than the first portion.
In an embodiment, the first portion of the flexion range includes flex angles of the sole plate less than a first predetermined flex angle, and the second portion of the sole plate includes flex angles greater than or equal to the first predetermined flex angle. Due to the tension member interfering with the sole plate in the second portion of the flexion range, the sole structure has a change in bending stiffness at the first predetermined flex angle. For example, the sole structure may provide a first bending stiffness in the first portion of the flexion range, and a second bending stiffness greater than the first bending stiffness in the second portion of the flexion range.
In an embodiment, the tension member is configured to be relatively slack when the portion of the tension member moves relative to the sole plate in the first portion of a flexion range and in tension when the sole plate interferes with the portion in the second portion of the flexion range.
In an embodiment, the portion of the tension member is displaced from the ground-facing surface of the sole plate by a vertical gap in the first portion of the flexion range and is in contact the ground-facing surface in the second portion of the flexion range. For example, the tension member may be fixed to the ground-facing surface of the sole plate at a first location and at a second location spaced apart from the first location during both the first portion of the flexion range and the second portion of the flexion range, and a midportion of the tension member may extend between the first location and the second location in suspension from the sole plate.
In an embodiment, only a forward portion of the tension member is fixed to the sole plate, and the portion that moves relative to the sole plate in the first portion of the flexion range is a rearward portion of the tension member. For example, the portion of the tension member may have a slot, and a post may extend at the ground-facing surface of the sole plate so that it is disposed in the slot. In such an embodiment, the slot moves relative to the plate during the first portion of the flexion range and the post abuts the tension member at an end of the slot in the second portion of the flexion range.
In an embodiment, the sole structure includes at least one protrusion at the ground-facing surface, and the tension member extends across the at least one protrusion such that at least a portion of the tension member is displaced from the foot-facing surface by at least a portion of the protrusion. There is at least one protrusion, or it may be a series of protrusions with gaps between the adjacencies of the protrusions, and the protrusions may vary in height so that the series of protrusions has a bowed profile. In an embodiment, the tension member confronts distal ends of the protrusions and slides along the distal ends during the first portion of the flexion range. The foot-facing surface may have recesses corresponding with the protrusions.
In an embodiment, the tension member is a relatively flat strap having a thickness, a width greater than the thickness, and a length greater than the width. The tension member is disposed lengthwise along a longitudinal midline of the sole plate. The strap may be any one of a variety of materials, including metal, a polymeric material, a composite, or fabric.
In an embodiment, the sole structure comprises at least one protrusion at the ground-facing surface. The at least one protrusion has an enclosed channel. The tension member is disposed in the channel. The channel may be generally U-shaped, with a midportion of the tension member restrained at a first location by the protrusion, and first and second end portions of the tension member both extending in a common direction from midportion.
In an embodiment, an enclosure at the ground-facing surface at least partially encloses the tension member. The enclosure may be at least partially transparent or translucent to enable viewing of the tension member through the enclosure.
The above features and advantages and other features and advantages of the present teachings are readily apparent from the following detailed description of the modes for carrying out the present teachings when taken in connection with the accompanying drawings.
“A,” “an,” “the,” “at least one,” and “one or more” are used interchangeably to indicate that at least one of the items is present. A plurality of such items may be present unless the context clearly indicates otherwise. All numerical values of parameters (e.g., of quantities or conditions) in this specification, unless otherwise indicated expressly or clearly in view of the context, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters. In addition, a disclosure of a range is to be understood as specifically disclosing all values and further divided ranges within the range.
The terms “comprising,” “including,” and “having” are inclusive and therefore specify the presence of stated features, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, or components. Orders of steps, processes, and operations may be altered when possible, and additional or alternative steps may be employed. As used in this specification, the term “or” includes any one and all combinations of the associated listed items. The term “any of” is understood to include any possible combination of referenced items, including “any one of” the referenced items. The term “any of” is understood to include any possible combination of referenced claims of the appended claims, including “any one of” the referenced claims.
Those having ordinary skill in the art will recognize that terms such as “above,” “below,” “upward,” “downward,” “top,” “bottom,” etc., are used descriptively relative to the figures, and do not represent limitations on the scope of the invention, as defined by the claims.
Referring to the drawings, wherein like reference numbers refer to like components throughout the views,
Referring to
Sole structure 10, includes the sole plate 12, the tension member 28, and, in some embodiments includes other layers and components. The sole structure 10 is secured to the upper 13 and has a configuration that extends between the upper 13 and the ground G (included in
In the embodiment shown, the sole plate 12 is a full-length, unitary sole plate 12 that has a forefoot portion 14, a midfoot portion 16, and a heel portion 18. The sole plate 12 provides a foot-receiving surface 20 (also referred to as a foot-facing surface) that extends over the forefoot portion 14, the midfoot portion 16, and the heel portion 18. The foot-facing surface 20 supports the foot 52 but need not be in contact with the foot 52. For example, an insole, midsole, strobel, or other layers or components may be positioned between the foot 52 and the foot-facing surface 20.
The sole plate 12 extends from a medial side 22 to a lateral side 24. In other embodiments, the sole plate 12 may be a partial length plate member. For example, in some cases, the sole plate 12 may include only a forefoot portion that may be operatively connected to other components of the article of footwear that comprise a midfoot portion and a heel portion. As shown, the sole plate 12 extends from the lateral side 22 to the medial side 24. As used herein, a lateral side of a component for an article of footwear, including the lateral side 22 of the sole plate 12, is a side that corresponds with an outside area of the human foot 52 (i.e., the side closer to the fifth toe of the wearer). The fifth toe is commonly referred to as the little toe. A medial side of a component for an article of footwear, including the medial side 24 of the sole plate 12, is the side that corresponds with an inside area of the human foot 52 (i.e., the side closer to the hallux of the foot of the wearer). The hallux is commonly referred to as the big toe. Both the lateral side 22 and the medial side 24 extend from a foremost extent 25 to a rearmost extent 29 of a periphery of the sole plate 12.
The term “longitudinal,” as used herein, refers to a direction extending along a length of the sole structure 10, e.g., extending from the forefoot portion 14 to the heel portion 18 of the sole structure 10. The term “forward” is used to refer to the general direction from the heel portion 18 toward the forefoot portion 14, and the term “rearward” is used to refer to the opposite direction, i.e., the direction from the forefoot portion 14 toward the heel portion 18. The term “anterior” is used to refer to a front or forward component or portion of a component. The term “posterior” is used to refer to a rear or rearward component or portion of a component.
The heel portion 18 generally includes portions of the sole plate 12 corresponding with rear portions of a human foot, including the calcaneus bone, when the human foot is supported on the sole structure 10 and is a size corresponding with the sole structure 10. The forefoot portion 14 generally includes portions of the sole plate 12 corresponding with the toes and the joints connecting the metatarsal bones with the phalange bones of the human foot (interchangeably referred to herein as the “metatarsal-phalangeal joints” or “MPJ” joints). The midfoot portion 16 generally includes portions of the sole plate 12 corresponding with an arch area of the human foot, including the navicular joint. Portions 14, 16, 18 are not intended to demarcate precise areas of the sole structure 10. Rather, portions 14, 16, 18 are intended to represent general areas relative to one another, to aid in the following discussion. In addition to the sole structure 10, the portions 14, 16, 18, and medial and lateral sides 22, 24 may also be applied to the upper 13, the article of footwear 11, and individual components thereof.
The sole plate 12 is referred to as a plate, but is not necessarily flat and need not be a single component but instead can be multiple interconnected components. For example, both an upward-facing portion of the foot-facing surface 20 and the opposite ground-facing surface 21 may be pre-formed with some amount of curvature and variations in thickness when molded or otherwise formed in order to provide a shaped footbed and/or increased thickness for reinforcement in desired areas. For example, the sole plate 12 could have a curved or contoured geometry that may be similar to the lower contours of the foot 52. For example, the sole plate 12 may have a contoured periphery that slopes upward toward any overlaying layers, such as a midsole component or the upper 13.
The sole plate 12 may be entirely of a single, uniform material, or may have different portions comprising different materials. For example, a first material of the forefoot portion 14 can be selected to achieve, in conjunction with the tension member 28 and other features and components of the sole structure 12 discussed herein, the desired bending stiffness in the forefoot portion 14, while a second material of the midfoot portion 16 and the heel portion 18 can be a different material that has little effect on the bending stiffness of the forefoot portion 14. By way of non-limiting example, the second portion can be over-molded onto or co-injection molded with the first portion. Example materials for the sole plate 12 include durable, wear resistant materials such as but not limited to nylon, thermoplastic polyurethane, or carbon fiber.
In the embodiment shown, the sole plate 12 may be an inner board plate, also referred to as an inner board, an insole board, or a lasting board. In other embodiments, the sole plate 12 may be an outsole. Still further, the sole plate 12 could be a midsole plate or a unisole plate, or may be any combination of an inner board plate, a midsole plate, or an outsole.
The tension member 28 is operatively secured to the ground-facing surface 21 of the sole plate 12. As used herein, a tension member is “operatively secured” to a sole plate when the tension member is directly or indirectly attached to the sole plate 12. In the embodiment of
In the embodiment shown in
In the embodiment shown, the forward portion 30 is the only portion of the tension member 28 fixed to the sole plate 12 during the entire flexion range of the sole structure 10. Those portions of the tension member 28 rearward of the forward portion 30, including the rear portion 32 that includes a slot 33, are configured to move relative to the sole plate 12 during a first portion of a flexion range FR1. The rearward portion 32 interferes with the sole plate 12 during dorsiflexion of the sole structure 10 in the second portion of a flexion range FR2. More specifically, with reference to
With reference to
The tension member 28 and the sole plate 12 including the protrusions 42 are configured so that, in the first portion of the flexion range FR1, the tension member 28 is in contact with and slides along the bottom facing surface 21 at the distal ends 40 of protrusions 42. This sliding action, in addition to the natural widening of the gaps G1 with increasing flex angle, could have the beneficial effect of dislodging debris that may have become lodged in the gaps G1 or between the tension member 28 and the distal ends 40. The gaps G1 are able to widen at least during the first portion of the flexion range FR1. In some embodiments, an enclosure similar to that described with respect to
The resistance to flexion and the bending stiffness of the sole structure 10 in the first portion of the flexion range FR1 is influenced by the thickness T2 of the sole plate 12 above the protrusions 42, but not significantly by the height of the protrusions 42 as the protrusions 42 move apart from one another unrestrained by the tension member 28 in the first portion of the flexion range FR1, such as when flexed at angle A shown in
At a first predetermined flex angle A1, which is the beginning of a second portion of the flexion range FR2, the post 34 abuts the tension member 28 at an end 35 of the slot 33 (shown in
With reference to
The sole structure 10 will bend in dorsiflexion in response to forces applied by corresponding bending of a user's foot at the MPJ during physical activity. Throughout the first portion of the flexion range FR1, bending stiffness (defined as the change in moment as a function of the change in angle) will remain approximately the same as bending progresses through increasing angles of flexion. Because bending within the first portion of the flexion range FR1 is primarily governed by inherent material properties of the materials of the sole plate 12, a graph of torque on the plate versus angle of flexion (the slope of which is the bending stiffness) in the first portion of the flexion range FR1 will typically demonstrate a smoothly but relatively gradually inclining curve (referred to herein as a “linear” region with constant bending stiffness). In the first portion of the flexion range FR1, the tension member 28 is under no tension, or under only minimal tension such as due to friction with the distal ends 40, in the first portion of the flexion range FR1. At the boundary between the first and second portions of the range of flexion FR1 and FR2, however, the abutment of the post 34 with the tension member 28 at the end 35 of the slot 33 engages additional material and mechanical properties that exert a notable increase in resistance to further dorsiflexion (i.e., the tension member 28 is placed under markedly increased tension, and the sole plate 12 is placed under compression by the tension member 28).
Therefore, a corresponding graph of torque versus angle of deflection (the slope of which is the bending stiffness) that also includes the second portion of the flexion range FR2 would show—beginning at an angle of flexion approximately corresponding to angle A1—a departure from the gradually and smoothly inclining curve characteristic of the first portion of the flexion range FR1. This departure is referred to herein as a “non-linear” increase in bend stiffness, and would manifest as either or both of a stepwise increase in bending stiffness and/or a change in the rate of increase in the bending stiffness. The change in rate can be either abrupt, or it can manifest over a short range of increase in the bend angle of the sole structure 10. In either case, a mathematical function describing a bending stiffness in the second portion of the flexion range FR2 will differ from a mathematical function describing bending stiffness in the first portion of the flexion range.
Functionally, when the sole plate 12 is dorsiflexed in the first portion of the flexion range FR1, as shown in
With reference to
As will be understood by those skilled in the art, during bending of the sole plate 12 as the foot 52 is dorsiflexed, there is a layer in the sole plate 12 referred to as a neutral plane (although not necessarily planar) or a neutral axis above which the sole plate 12 is in compression, and below which the sole plate 12 is in tension. The interference of the tension member 28 with the post 34 while abutting the distal end 40 places the tension member 28 in tension and causes additional compressive forces CF1 on the sole plate 12 above the neutral plane, and additional tensile forces TF2 below the neutral plane, nearer the ground-facing surface 21.
In addition to the mechanical (e.g., tensile, compression, etc.) properties of the selected material of the sole plate 12 and the tension member 28, structural factors that likewise affect changes in bend stiffness during dorsiflexion include but are not limited to the thicknesses, the longitudinal lengths, and the medial-lateral widths of the sole plate 12, including the protrusions 42, and the tension member 28.
Traction elements 69 are shown in
Referring again to
In other embodiments, the protrusions 42 could instead be a single, solid protrusion having the bowed profile provided by the series of protrusions 42. Additionally, in an embodiment, instead of confronting the distal end 40 of each protrusion 42, each of the protrusions 42 could have an aperture, and the apertures could be aligned so that the tension member 28 could extend through the apertures and rest against a surface of each protrusion 42 with the aperture nearest the foot-facing surface 20 (i.e., an upper surface of the aperture).
In another embodiment, a cover or enclosure that may be integral with or separate from the sole plate 12 can enclose the tension member 28 and the gaps G1. For example,
The sole structure 110 includes a sole plate 112 with an enclosure 170 at the ground-facing surface 121 that encloses the tension member 28. The enclosure 170 protects the tension member 28 from reacting against an uneven ground surface, and from contamination with debris. The enclosure 170 may be transparent or translucent, or have at least a portion that is transparent or translucent, in order to enable viewing of the tension member 28 through the enclosure 170.
The sole plate 112 has recesses 172 at the foot-facing surface 120 that correspond with protrusions 142 at the ground-facing surface 121. The protrusions 142 are thus relatively thin-walled in comparison to the solid protrusions 42 indicated by the cross-sectional view of
The protrusion 342 has an enclosed channel 380. The enclosed channel 380 generally has an elongated U shape (i.e., the channel 380 is U-shaped), with a forward branch 382 extending generally transversely, and first and second arm branches 384, 386, respectively, spaced from one another and extending in a common direction (i.e., generally in a longitudinal rearward direction) from the forward branch 382. A tension member 328 is disposed in the channel 380. A midportion 335 of the tension member 328 is disposed in the forward branch 382, and first and second arm portions 330, 332 of the tension member 328 both extend generally rearward in the longitudinal direction from the midportion 335, with the first arm portion 330 disposed in the first arm branch 384, and the second arm portion 332 disposed in the second arm branch 386. The tension member 328 is restrained by the body of protrusion 342 at a first location 388, namely the portion of the protrusion 342 between the branches 384, 386. First and second ends 386A, 386B of the tension member are restrained at a second location rearward of the first location by rivets 331 or otherwise. The ends 386A, 386B of the tension member 328 may be fixed by the rivets 331. In that case, the length of the tension member 328 may be selected so that there is some slack in the arm portions 330, 332 when the sole structure is in the relaxed, unflexed state shown in
A cross-section of the channel 380 perpendicular to its length along one of the arm portions 330, 332 may be generally circular. The tension member 328 may be a cable with a generally circular cross-section. The tension member 328 is longer than the channel 380 so that some slack is afforded in the tension member 328 in the relaxed state of the sole structure 310. The slack allows the tension member 328 to initially move relative to the sole plate 312 as the slack in the tension member 328 is taken up during dorsiflexion in a first portion of the flexion range FR1. Bending stiffness of the sole structure 310 in the first portion of the flexion range FR1 thus generally corresponds with the bending stiffness of the sole plate 312. At the first predetermined flex angle A1, the tension member 328 is no longer slack, and dorsiflexion of the forefoot portion 14 causes the midportion 335 to interfere with the body 387 of the protrusion 342 at the first location 388. Accordingly, tension occurs in the tension member 328, with outwardly opposing tensile forces acting on the midportion 335 (due to the body 387) and at the ends 386A, 386B. Bending stiffness of the sole structure 310 in the second portion of the flexion range FR2 is further affected by compression of the sole plate 312 as well as tension of the tension member 328. The sole structure 310 thus provides an increased bending stiffness in the second portion of the flexion range FR2 relative to the first range of flexion FR1 resulting in a non-linear bending stiffness.
While several modes for carrying out the many aspects of the present teachings have been described in detail, those familiar with the art to which these teachings relate will recognize various alternative aspects for practicing the present teachings that are within the scope of the appended claims. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not as limiting.
This application claims the benefit of priority to U.S. Provisional Application Ser. No. 62/343,432 filed May 31, 2016, which is incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62343432 | May 2016 | US |
