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Publication numberUS20080148598 A1
Publication typeApplication
Application numberUS 12/047,735
Publication dateJun 26, 2008
Filing dateMar 13, 2008
Priority dateMay 18, 2006
Also published asCA2576792A1, CN101073451A, EP1857003A2, EP1857003A3, US7398608, US20060277792
Publication number047735, 12047735, US 2008/0148598 A1, US 2008/148598 A1, US 20080148598 A1, US 20080148598A1, US 2008148598 A1, US 2008148598A1, US-A1-20080148598, US-A1-2008148598, US2008/0148598A1, US2008/148598A1, US20080148598 A1, US20080148598A1, US2008148598 A1, US2008148598A1
InventorsMary L. Schoenborn
Original AssigneeWolverine World Wide, Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Footwear sole
US 20080148598 A1
Abstract
A sole for an article of footwear having an insert with a plurality of forefoot support tubes are configured to control the support characteristics of the sole in a forefoot region of the sole. In one embodiment, the forefoot support tubes each include a base, and a wall extending from the base. The wall is formed from a material that has a lower durometer value than the base. In another embodiment, the forefoot support tubes are arranged in a radiating pattern, such that at least two of the forefoot support tubes diverge as they extend toward the lateral side of the insert.
Images(19)
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Claims(15)
1. An article of footwear comprising:
a two-component insert including a plurality of resilient compressible front support tubes, each of said front support tubes defining a base, and a wall extending from said base, wherein said base is formed from a first material, and said wall is formed from a second material softer than said first material, and;
an outsole positioned below said insert and forming a ground engaging wear surface for the article of footwear.
2. The article of footwear of claim 1 wherein said insert includes a lateral side and a medial side, and wherein at least two of said front support tubes are arranged in a radiating pattern such that they diverge as they extend from said medial side towards said lateral side.
3. The article of footwear of claim 2 wherein said insert includes a forefoot portion, said front support tubes positioned in said forefoot portion.
4. The article of footwear of claim 1 wherein said bases of each of said support tubes are connected to form a forefoot web, said forefoot web formed from said first material.
5. The article of footwear of claim 1 wherein said insert includes an arch portion and a heel portion, said heel portion including a plurality of resilient compressible rear support tubes, each of said rear support tubes defining an internal void; and a plurality of webs, each of said webs being disposed within a corresponding one of said rear support tubes and extending at an orientation, said orientation of each of said webs being pre-selected to provide said insert with a support profile.
6. The article of footwear of claim 1 wherein said front support tubes include a first end and a second end, at least one of said first and second ends of each of said front support tubes being open.
7. The article of footwear of claim 6 wherein at least one of said first and second ends of at least one of said front support tubes is closed.
8. The article of footwear of claim 6 wherein at least one of said first and second ends of each of said front support tubes includes a generally flat base and a generally semi-circular wall extending from said base.
9. The article of footwear claim 1 wherein said plurality of front support tubes includes at least one central support tube and at least two peripheral support tubes on opposite sides of said at least one central support tube, said at least one central support tube extending substantially across the lateral extent of said insert, said peripheral support tubes extending from the lateral side of said insert only partially across said insert.
10. An article of footwear having a forefoot region, the article of footwear comprising:
a two-component insert permanently affixed in the article of footwear, said insert including a lateral side, a medial side and a plurality of resilient compressive front support tubes, said front support tubes positioned in the forefoot region of the article of footwear and extending laterally across at least a portion of said insert, at least two of said front support tubes positioned in a radiating arrangement such that said at least two of said front support tubes diverge as they extend toward said lateral side of said insert, each said support tube including a base comprised of a first material and a wall extending from the base and formed from a second material, said second material being softer than said first material;
a cushioned midsole disposed above said insert; and
an outsole disposed below said insert and forming a wear resistant, ground engaging surface of the article of footwear.
11. The article of footwear of claim 10 wherein said plurality of front support tubes include at least one central front support tube, and at least one peripheral front support tube, said central front support tube extending substantially across said insert, said peripheral front support tube extending partially across said insert.
12. The article of footwear of claim 11 wherein at least one of said front support tubes has a semi-circular cross section.
13. The article of footwear of claim 11 wherein said at least one peripheral front support tube extends from an open end adjacent to said lateral side of said insert to a closed end partially across said insert.
14. The article of footwear of claim 11 wherein said at least one peripheral front support tube tapers to a point at said closed end.
15. An article of footwear having a forefoot region, the article of footwear comprising:
an upper;
an outsole having a ground engaging surface and an upper surface; and
an insert between said upper and said outsole, said insert positioned in the forefoot region of the article of footwear, said insert including a base formed from a first material, and a plurality of support tube walls attached to said base and extending upwardly from said base, said plurality of support tube walls formed integrally with each other from a second material that is softer than said first material.
Description
    BACKGROUND OF THE INVENTION
  • [0001]
    The present invention relates to footwear, and more particularly to a sole construction for an article of footwear.
  • [0002]
    There is a continuing effort to provide ever more comfortable footwear. Running shoes, as well as other footwear, have undergone tremendous evolutionary advances in technology over the past 20 years. Many of the technological advances have occurred in the midsole. In most footwear, the midsole functions as the “suspension system” of the sole and it often provides both protective cushioning and a stable platform for the wearer's foot. Variations in the characteristics of the midsole can have a dramatic affect on the performance of the shoe. In an effort to provide improved performance, it is often desirable to vary the support characteristics of the sole from one region to another. For example, it may be desirable to provide a higher density material in the heel and a lower density material in the forefoot. A higher density material in the heel provides greater support upon heel strike while a lower density material provides appropriate cushioning and support for the typically smaller loads encountered in the forefoot. A wide variety of soles have been developed to provide variable support over the foot. In some applications, variable support is provided by forming different regions of the midsole from different materials, such as softer EVA foam in the forefoot and firmer EVA foam in the heel. In other applications, the sole is provided with a support plate that can be configured to provide the sole with the desired overall support profile. Although a marked improvement over conventional uniform sole constructions, there remains a need for a sole construction that is inexpensive to manufacture and that is highly tunable with a wide range of adjustability.
  • [0003]
    At the same time, there is also an ongoing effort to extend the life of footwear soles. In conventional footwear, the midsole (as well as other sole components) may begin to lose its performance over a relatively short period of time. Degradation of the sole material can cause the sole to lose its resiliency over time, particularly in regions of high and repeated impact, such as the heel. The rate of degradation will vary from sole to sole, but is largely dependent on the specific characteristics of the sole material and the types of loads applied to the sole. For example, conventional closed and open cell foams, such as EVA, have a relatively short life as the material naturally breaks down over relatively short periods of use. Conventional foam materials are also susceptible to temperature changes, which can cause the resiliency of the foam to vary noticeably. For example, the sole may become noticeably stiffer in colder temperatures and noticeably softer in higher temperatures. As a result, temperature can have a significant adverse affect on the support characteristics of a sole manufactured from conventional foam materials.
  • [0004]
    Accordingly, there remains a need for a highly reliable, highly tunable sole that has an extended life and is relatively inexpensive to manufacture.
  • SUMMARY OF THE INVENTION
  • [0005]
    The aforementioned problems are overcome by the present invention which provides a sole having an insert with a plurality of support tubes that are tuned to provide the desired support profile. Each support tube may include an internal web having an orientation that is selected to provide the desired support characteristics. By varying the orientation of the webs from support tube to support tube, the overall support profile of the sole can be controlled.
  • [0006]
    In one embodiment, the support layer is disposed between the outsole and the midsole. If desired, the sole may further include a heel wedge disposed between the outsole and the insert in the heel region. The heel wedge may be manufactured from a material that is firmer than the midsole material. As a result, the heel wedge may provide additional support in the heel region of the sole.
  • [0007]
    In another embodiment, the insert may include a plurality of support tubes on the medial (or inner) side of the sole and a plurality of support tubes on the lateral (or outer) side of the sole. The internal webs may be disposed in a more vertical orientation along the medial side of the sole to provide greater vertical support on the medial side of the sole. If desired, the orientation of the webs can vary from tube to tube. For example, the webs may be oriented in an increasingly more vertical direction moving from front to rear to provide increasingly more vertical support toward the rear of the heel. The support tubes on the medial side may be connected to the support tubes on the lateral side by struts. The struts may be concave to provide the heel with an inherent centering capability.
  • [0008]
    In yet another embodiment, the support tubes are disposed in at least a portion of the heel region of the insert and the insert includes an arch portion extending through the arch region of the sole. The arch portion of the insert may include two layers spaced apart from one another to provide a structure to receive a gaiter strap. The lower layer helps to protect the gaiter strap from damage associated with ground contact. If desired, the insert may further include a forefoot extension that extends through at least a portion of the forefoot region of the sole. The forefoot extension may extend only along the medial side of the forefoot region to provide a sole that is more rigid along the medial side. The forefoot extension may extend through different regions of the forefoot or may cover the entire forefoot region, as desired.
  • [0009]
    In another embodiment of the present invention, the insert includes a plurality of front support tubes. In one embodiment, the front support tubes are positioned in the forefoot region and extend across the forefoot region from the medial side to the lateral side of the sole. The front support tubes may be arranged in a radiating pattern such that they diverge as they approach the lateral edge of the sole. In another embodiment, the front support tubes are formed from a first material that forms a base, and a second material that extends upwardly from the base and has a lower durometer value than the first material.
  • [0010]
    The present invention provides a unique footwear sole that can be easily tuned to provide the desired support profile. The insert may be manufactured from TPU or other relatively durable materials that do not degrade as quickly as conventional foam materials and therefore extend the cushioning life of the midsole. The support profile may be varied between the medial and lateral sides of the sole. For example, the support tubes on the medial side of the sole can be tuned to provide increasing vertical stiffness toward the back of the shoe, thereby address the problem of overpronation. The insert is relatively inexpensive to manufacture and its support characteristics can be readily adjusted by controlling, among other things, the nature and orientation of the support tubes and the webs. The insert can be combined with a heel wedge to provide even greater control over its support profile. The arch portion of the insert can be tuned to provide control over the support profile of the sole in the arch region. The gaiter slot can be incorporated into the arch portion to protect a gaiter strap from premature wear. The support profile of the sole in the forefoot region can be controlled through the use of the forefoot extension. When included, the struts assist in centering the foot on heel strike. The front support tubes enable controlled cushioning in the forefoot regions and can be arranged in proper alignment for an efficient toe-off.
  • [0011]
    These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0012]
    FIG. 1 is an exploded perspective view of a sole in accordance with an embodiment of the present invention.
  • [0013]
    FIG. 2 is a medial side elevational view of the shoe.
  • [0014]
    FIG. 3 is a side elevational view of the midsole.
  • [0015]
    FIG. 4 is a top plan view of the midsole.
  • [0016]
    FIG. 5 is a bottom plan view of the midsole.
  • [0017]
    FIG. 6 is a top plan view of the insert.
  • [0018]
    FIG. 7 is a bottom plan view of the insert.
  • [0019]
    FIG. 8A is a right (medial) side elevational view of the insert.
  • [0020]
    FIG. 8B is a left (lateral) side elevational view of the insert.
  • [0021]
    FIG. 9 is a side elevational view of the heel wedge.
  • [0022]
    FIG. 10 is a bottom plan view of the insert and midsole.
  • [0023]
    FIG. 11 is a bottom plan view of the insert, midsole and heel wedge.
  • [0024]
    FIG. 12 is a bottom plan view of the shoe.
  • [0025]
    FIG. 13 is an exploded perspective view of a sole in accordance with another aspect of the present invention.
  • [0026]
    FIG. 14 is a top view of the insert according to the second embodiment.
  • [0027]
    FIG. 15 is a medial side view of the insert according to the second embodiment.
  • [0028]
    FIG. 16 is an exploded perspective view of the insert according to the second embodiment.
  • [0029]
    FIG. 17 is a lateral side view of the insert according to the second embodiment.
  • DETAILED DESCRIPTION OF THE CURRENT EMBODIMENTS
  • [0030]
    A footwear sole manufactured in accordance with an embodiment of the present invention is shown in FIG. 1, and generally designated 10. The footwear sole 10 generally includes an outsole 12, a heel wedge, 14, an insert 16 and a midsole 18. The sole 10 may be incorporated into an article of footwear, such as shoe 200 shown in FIG. 2. The shoe 200 may include an upper 202 that is affixed to the sole 10. The shoe 200 may also include a footbed (not shown) that is removably fitted into the upper 202 atop of the sole 10. The insert 16 may include support tubes 46 a-j with internal webs 48 a-j that are configured to control the support profile of the sole 10. Although the present invention is described in connection with a conventional standard height running or trail running shoe 200, the present invention is not limited to use in shoes of that type. The present invention is well-suited for use in essentially any type of sole and can be incorporated into essentially any type of footwear. The footwear sole 10 is intended to be secured to an upper (not shown) using essentially any attachment construction, including without limitation cement, stitch, welt and direct attach constructions. The footwear sole 10 may also include a shank or other conventional sole components, as desired.
  • [0031]
    To facilitate disclosure of the present invention, reference will be made to various general areas of the foot, such as the heel, arch and forefoot areas. When used to refer to locations on the various sole components, these terms should be interpreted to include those areas of the sole that are disposed generally (and not necessarily directly) beneath the corresponding elements of the foot. For purposes of general reference only, the heel area is generally defined as that area behind (toward the rear of the heel of the sole 10) phantom line A1 (See FIG. 2), the arch area is generally defined as that area between phantom lines A1 and A2 and the forefoot region is generally defined as that area ahead of (toward the tiptoe of the sole 10) phantom line A2. It should be understood, however, that the boundaries between the heel, arch and forefoot areas are not precise and that these terms should be interpreted loosely and with a great deal of flexibility.
  • [0032]
    In the described embodiment, the outsole 12 is generally conventional and defines the primary wear surface for the sole 10. The outsole 12 is generally conventional and is secured to the bottom of the sole 10 to provide a durable and non-slip wear surface (See FIG. 2). The design and configuration of the outsole 12 may vary from application-to-application. However, in the illustrated embodiment, the outsole 12 is a two-piece outsole having a main part 20 and heel part 22 (See FIGS. 1 and 12). The main part 20 of this embodiment extends across portions of the heel wedge 14, insert 16 and midsole 18. The main part 20 is cemented or otherwise secured to the bottom of the various sole components 14, 16 and 18 using generally conventional techniques and apparatus. The heel part 22 is disposed at the back of the heel and is cemented to the undersurface of the heel wedge 14 using generally conventional techniques and apparatus. Separation of the main part 20 and the heel part 22 provides the outsole 12 with a degree of articulation in the heel. The lower surface of each part 20 and 22 includes a plurality of lugs or other traction elements, which are generally identified in the drawings by reference numeral 24. The design and configuration of the traction elements 24 may vary from application to application as desired. The outsole 12 may be manufactured from a wide variety of conventional sole materials, such as natural and synthetic rubbers, leather, PVC, EVA and polyurethane.
  • [0033]
    As noted above, the sole 10 includes a heel wedge 14 disposed above the outsole 12 in the heel region (See FIGS. 1 and 2). The heel wedge 14 provides a resilient, compressible platform for the insert 16 as described in more detail below. Referring now to FIG. 9, the heel wedge 14 is generally wedge-shaped having an upper surface 26 that is contoured to compliment the shape of the bottom surface 30 of the insert 16 and a lower surface 32 that is contoured to compliment the shape of the upper surface 34 of the outsole 12. More specifically, the upper surface 26 of the illustrated embodiment includes a plurality of tube recesses 36 a-j that corresponds in shape with the support tubes 46 a-j. The tube recesses 36 a-j closely receive the support tubes 46 a-j in the assembled sole 10. The heel wedge 14 may be manufactured from a variety of sole material, such as EVA and polyurethane. In the illustrated embodiment, the heel wedge 14 defines a central opening 80 that is aligned with a corresponding absence of material in the heel region of the outsole 12. Among other things, the opening 30 permits viewing of portions of the midsole 16 and insert 18. As perhaps best shown in FIG. 11, the heel wedge 14 may include an arrangement of small ridges 86 on its undersurface 88 that, among other things, provide a guide for placing the outsole 12 parts. In the illustrated embodiment, the heel wedge 14 extends only through the heel region of the sole 10 and is generally wedge-shaped. The heel wedge 14 may extend through different regions of the sole and may, for example, extend through the arch region or be coextensive with the entire sole. The heel wedge 14 is not necessarily wedge-shaped and may take on different thickness configurations as desired. In the illustrated embodiment, the heel wedge 14 is manufactured from EVA foam having a durometer value of approximately 55-60 Asker C Scale. The type of material and density of the heel wedge 14 material may, however, vary from application to application. If desired, the density of the heel wedge 14 may vary from region to region within the heel wedge 14.
  • [0034]
    The insert 16 is disposed above the outsole 12 and the heel wedge 14, and provides the sole 10 with a highly tuned support profile (See FIGS. 1 and 2). Referring now to FIGS. 6, 8, 8A and 8B, the insert 16 generally includes a heel portion 40, an arch portion 42 and a forefoot extension 44. The heel portion 40, as its name implies, extends through at least a portion of the heel region of the sole 10 and includes a plurality of support tubes 46 a-j. In the illustrated embodiment, the support tubes 46 aj extend in a generally lateral orientation. The insert 16 may include a first plurality of support tubes 46 a-e extending through a peripheral marginal portion of the lateral side of the heel region (“lateral support tubes”) and a second plurality of support tubes 46 fj extending through a peripheral marginal portion of the medial side of the heel region (“medial support tubes”). The medial support tubes 46 fj and lateral support tubes 46 a-e may be spaced apart so that the support tubes 46 aj do not extend through the central region of the sole 10. The absence of support tubes 46 aj in the central region may provide a relatively soft center that helps to center the wearer's foot on the sole 10. The use of separate medial and lateral support tubes is not strictly necessary, and in some applications, the support tubes may be located only on one side or may extend entirely across the sole 10. In the illustrated embodiment, the support tubes 46 aj are generally annular in cross-section. The support tubes 46 aj may alternatively have other cross-sectional shapes (both regular and irregular), such as oval, square, rectangular and triangular. The characteristics of each support tube 46 aj may be varied to control its particular response to different loads. For example, the number, shape, diameter, length and wall thickness of the support tubes 46 aj may be varied to tune the support characteristics of the sole 10. Each support tube 46 a-j may also include an internal web 48 a-j that affects the support characteristics of the tube 46 a-j. In the illustrated embodiment (where the support tubes 46 a-j are generally annular in cross-section), the webs 48 a-j are chords, and more particularly extend along diameters of the support tubes 48 a-j. But, the characteristics of each web 48 a-j may be varied to control its affect on the support characteristics. For example, the number, orientation, position, length and thickness of the webs 48 a-j can be varied. In the illustrated embodiment, the lateral support tubes 46 a-e each include a web 48 a-e that extends in a generally horizontal direction following the general extent of the insert 16. Accordingly, the webs 48 a-e have little affect on the rigidity of the lateral support tubes 46 a-e in the vertical direction. In the illustrated embodiment, the orientation of the webs 48 fj of the medial support tubes 46 fj varies from front to rear. More specifically, the medial webs 48 f-i are arranged at a more vertical orientation toward the rear of the heel region as can be seen in FIGS. 2 and 8A. As a result, the medial support tubes 46 fj provide increasingly more resistance to vertical compression toward the rear of the heel region. In the illustrated embodiment, the webs 48 a-j are integrally formed with the support tubes 46 aj. This is not, however, strictly necessary and the webs 48 aj may alternatively be separately manufactured, for example, as inserts that are fitted into the support tubes 46 a-j.
  • [0035]
    The insert 16 may also include a plurality of struts 38 a-d that join the support tubes 48 a-d on one side of the sole 10 with the support tubes 48 f-I on the opposite side. The characteristics of the struts 38 a-d may be varied to control the support characteristics of the sole 10. For example, changes in the number, width, thickness and shape of the struts 38 a-d will impact the support characteristics of the insert 16. As shown, the struts 38 a-c are of this embodiment are generally concave to follow a convex structure on the undersurface of the midsole 18. In this embodiment, the struts 38 a-c are concave primarily to accommodate recess 64 and plug 62.
  • [0036]
    The arch portion 42 of the illustrated embodiment is integral with and extends from the heel portion 40. It may alternatively be a separate component. The arch portion 42 includes a pair of wings 50 a-b that extend upwardly from its lateral and medial edges. The wings 50 a-b may be cemented or otherwise secured to the midsole 18. In use, the wings 50 a-b provide the midsole 18 with enhanced support in the arch region. The arch portion 42 may also define a slot 52 for receiving the strap of a gaiter. The arch portion 42 of the illustrated embodiment includes a pair of spaced apart layers 54 a-b that cooperatively define the slot 52. The size, shape and configuration of the layers 54 a-b may vary from application to application as desired. The arch portion 42 is optional and may be eliminated, if desired.
  • [0037]
    The forefoot extension 44 of the illustrated embodiment is integral with and extends from the arch portion 42. It may alternatively be a separate component. The forefoot extension 44 may extend only along a peripheral portion of the medial side of the sole 10 (as shown in the illustrated embodiment). It may, however, be designed to extend through essentially any portion of the forefoot region or over the entire forefoot region, if desired. The forefoot extension 44 may define a plurality of flex slots 56 a-c configured to provide flex points. The forefoot extension 44 is optional and may be eliminated in some applications, as desired.
  • [0038]
    The insert 16 may be manufactured from a variety of conventional materials, but typically it will be manufactured from a material that is stiffer than the heel wedge 14 and/or midsole 18. For example, the insert 16 may be injection molded from TPU, TPR or PVC. The insert 16 may be manufactured from other materials, such as nylon, rubber, synthetic rubber or silicone, but it is likely that the insert 16 would not be manufactured by injection molding if any of these alternative materials was used. If desired, the insert 16 may be manufactured from a collection of different materials. For example, the arch portion 42 may be manufactured from a stiffer material than the heel portion 40.
  • [0039]
    In the illustrated embodiment, the support tubes 46 a-j extend only through the heel region of the sole 10. In alternative embodiments, the support tubes 46 a-j may in addition (or alternatively) extend through the arch and/or forefoot regions of the sole. The size, configuration, layout and other characteristics of the support tubes 46 a-j may vary from region to region and from application to application.
  • [0040]
    The midsole 18 is disposed between the insert 16 and the upper 202, and is designed to provide a compressible, resilient foot platform (See FIGS. 1 and 2). As it is designed to support the foot and to be incorporated into conventional footwear, the midsole 18 is generally foot-shaped. The midsole 18 may, however, take on other shapes, as desired, to accommodate various alternative sole designs. In the illustrated embodiment, the midsole 18 is manufactured from EVA foam having a durometer value of approximately 55-60 Asker C Scale. The type of material and density of the midsole 18 material may, however, vary from application to application. In the illustrated embodiment, the midsole 18 is a one-piece, unitary structure, but it may alternatively include a collection of separate elements that cooperatively support the foot. For example, in an alternative embodiment, the midsole 18 may include a forefoot segment that is manufactured from a relatively soft material and heel region manufactured from a more rigid material. The midsole 18 includes a generally smooth upper surface 60 designed to support the wearer's foot (See FIG. 4). The upper surface 60 may include contours, if desired. For example, the upper surface 60 of the midsole 18 may be contoured to match the natural contours of the wearer's foot, for example, by providing the upper surface 60 with a concave heel area, a raised arch area or essentially any other desired shape. The midsole 18 of the illustrated embodiment includes a peripheral lip 68 that extends upwardly around the peripheral edge of the midsole 18. The midsole 18 may directly engage the undersurface of the wearer's foot. In most applications, however, an additional component (not shown) will be incorporated into the sole 10 above the midsole 18. For example, an insole (not shown), sock liner (not shown), footbed (not shown) or other sole element may be incorporated into the sole 10 above the midsole 18. This additional component may be removably fitted into the shoe 200 atop the sole 10.
  • [0041]
    In the illustrated embodiment, the midsole 18 includes a disc-shaped plug 62 that is fitted into a corresponding recess 64 in the heel area (See FIG. 1). The plug 62 is manufactured from a relatively soft cushioning material, such as closed cell foam. In the illustrated embodiment, the plug 62 is manufactured from a material having a lower density than the material of the midsole 18. As a result, the plug 62 and recess 64 combination help to center the foot in the heel of the sole 10. The size, shape and configuration of the plug 62 and recess 64 may vary from application to application. For example, the plug 62 and recess 64 combination may be replaced by one or more perforations or cutouts that reduce the resistance of the corresponding region to compression. In this embodiment, the recess 64 is vertically aligned with the convex region of the struts, but that is not strictly necessary.
  • [0042]
    The midsole 18 may be configured to provide ventilation as shown in the illustrated embodiment. In this embodiment, the midsole 18 defines a plurality of ventilation holes 70 through the sidewall of the midsole 18 and a series of ventilation channels 72 in the upper surface 60 of the midsole 18 (See FIG. 4). The ventilation channels 72 communicate with the ventilation holes 70 to permit air and water to ventilate through the midsole 18 (See FIG. 3). Again, this is optional and the present invention may be incorporated into a non-ventilated midsole as desired.
  • [0043]
    Referring again to FIG. 4, the midsole 18 may also include a plurality of flex grooves 74 a-c to facilitate flexing of the midsole 18. In the illustrated embodiment, the midsole 18 includes flex grooves 74 a-c extending substantially laterally across the sole 10 in the forefoot region. If desired, the flex grooves 74 a-c may be eliminated or replaced by other structure intended to improve flexibility. For example, the flex grooves 74 a-c may be replaced by a relatively shallow recess (not shown) in the top surface of the midsole 18 that is filled with a pad (not shown). The pad may have a lower density than the material of the midsole 18. The pad may be cemented within the recess.
  • [0044]
    The undersurface 66 of the midsole 18 may be contoured to compliment the shape of the outsole 12, heel wedge 14 and insert 16 (See FIG. 5). In the illustrated embodiment, the undersurface 66 of the midsole 18 is contoured to define a plurality of support tube recesses 78 that are adapted to closely receive the support tubes 46 a-j of the insert 16. If desired, an insert recess 76 may be defined in the undersurface 66 so that the insert 16 can be recessed or inset into the midsole 18. For example, the midsole 18 may define a plurality of strut recesses 82 adapted to receive the struts 38 a-d of the insert 16. The recess 76 may also extend through the extents of the arch portion 42 (including the wings 50 a-b) and forefoot extension 44. Alternatively (or in addition), recesses (not shown) may be formed in the top surface of the outsole 12 to receive all or a portion of the insert 16.
  • [0045]
    The midsole 18 and heel wedge 14 are separate components in the illustrated embodiment. The present invention extends, however, to applications in which the midsole and heel wedge are integral. For example, in an alternative embodiment, the appropriate material (e.g. EVA foam) may be injected or poured into a mold about the insert to entrap the insert in a single piece midsole/heel wedge combination.
  • Alternative Embodiment
  • [0046]
    An alternative embodiment of the footwear sole of the present invention is shown in FIGS. 13-17, and generally designated 100. In this embodiment, the insert 160 includes a plurality of forefoot support tubes 510 a-e. Similar to the first described embodiment, the insert 160 is disposed above the outsole 120 and the heel wedge 140, and provides the sole with a highly tuned support profile in the forefoot region. Referring now to FIGS. 14-17, the insert 160 may include a heel portion 400, an arch portion 420 and a forefoot portion 440. The heel portion 400 is generally the same as the heel portion 40 described in connection with the first embodiment, and therefore will not be described again in detail. Suffice it to say that the heel portion 400 may include support tubes 460 a-j including internal webs, and struts 380 a-d. Similarly, the arch portion 420 is generally the same as the arch portion 42 described in connection with the first embodiment. The arch portion 420 includes a pair of wings 500 a-b that extend upwardly from its lateral and medial edges. The wings 500 a-b include a plurality of holes 502 extending therethrough. The arch portion 420 may also define a slot 520 for receiving the strap of a gaiter—as shown, the slot 520 is formed by first and second layers 540 a-b. The slot 520 may be oval in shape as illustrated, however, the slot 520 may have a variety of shapes. Both the arch portion 420 and the heel portion 400 are optional and may be eliminated, if desired.
  • [0047]
    In the illustrated embodiment, the forefoot portion 440 of the alternative embodiment is integral with and extends from the arch portion 420. It may alternatively be a separate component, or the only component if the heel portion 400 and/or the arch portion 420 are eliminated. A plurality of forefoot support tubes 510 a-e are provided in the forefoot portion, or at least at a position in front of the arch region. In the illustrated embodiment, three of the central forefoot support tubes 510 b-d extend laterally all the way across the insert 160, and a peripheral two of the forefoot support tubes 510 a and 510 e extend from the lateral side of the insert 160 partially across the insert 160 where they converge to a point at a closed end 530. Functionally, these two support tubes 510 a and 510 e are stiffer at the closed end than they are at the open end. The forefoot support tubes may be positioned in a radiating arrangement, to enable an efficient toe-off towards the medial side of the shoe 100. As illustrated, forefoot support tubes 510 c and 510 d are positioned in a radiating arrangement, such that they diverge as they extend from the medial side to the lateral side of the insert 160. Alternatively, more than two of the forefoot support tubes 510 a-e may be arranged radially, or in another arrangement.
  • [0048]
    As shown in FIGS. 16 and 17, in one embodiment, the forefoot support tubes 510 a-e each include a generally flat base 550 a-e, and a generally semi-circular wall 570 a-e extending upwardly from the base 550 a-e and forming a tube. The upwardly extending walls 570 a-e may alternatively have a variety of shapes. They may be hollow, as shown, or may be filled with a support material, such as EVA. In another embodiment, the bases may have different shapes, for example, they may be semi-circular to form round tubes. In yet another embodiment, the walls may extend downwardly from the base, or both upwardly and downwardly from the base.
  • [0049]
    The bases 550 a-e of each forefoot support tube 510 may be integrally connected to each other and to the arch portion 420, for example, as a forefoot extension of the insert 160. As shown, the bases 550 a-e are integrally connected to each other to form a web 590 extending from the arch portion 420. The web 590 is cut off just in front of the forward most forefoot support tube 510 a. It may, however, be designed to extend through essentially any portion of the forefoot region or over the entire forefoot region, if desired. Alternatively, one or more of the bases and forefoot support tubes may be separate sections. As shown, the web 590 additionally integrally includes a peripheral portion of each of the upwardly extending walls 570 a-e. Referring to FIGS. 14 and 16, a first set of loops 610 a-e extend upwardly from the web 590 to form a first peripheral portion of the forefoot support tubes 510 a-e on the lateral side of the insert 160. A second set of loops 630 a-c extend upwardly from the web 590 to form a second peripheral portion of the forefoot support tubes 510 a-e on the medial side of the insert 160. The web 590 may additionally define a plurality of flex slots 560 configured to provide flex points. As in the first embodiment, the insert 160 can be attached to the outsole 120 by a variety of conventional methods.
  • [0050]
    The insert 160, including the forefoot support tubes 510 a-e, may be manufactured from a variety of conventional materials, but typically it will be manufactured from a material that is stiffer than the heel wedge 140 and/or midsole (not shown). For example, the insert 160 may be injection molded from TPU, TPR, PVC or other injected polymers. The insert 160 may be manufactured from other materials, such as nylon, rubber, synthetic rubber or silicone, but it is likely that the insert 160 would not be manufactured by injection molding if any of these alternative materials was used. If desired, the insert 160 may be manufactured from a collection of different materials. For example, the arch portion 420 may be manufactured from a stiffer material than the heel portion 400.
  • [0051]
    Referring now to FIG. 16, in one embodiment, the forefoot support tubes 510 a-e are formed from two different materials. The web 590, including base portions 550 a-e and the first and second sets of loops 610 a-e and 630 a-c, are formed from a first material. The upwardly extending walls 570 a-e are formed from a second material. In the illustrated embodiment, the upwardly extending walls 570 a-e are connected together by an upper web 650, such that they may be formed from a single piece of the second material. As illustrated, all of the insert 160 except for the upwardly extending walls 570 a-e is formed from the first material. The second material is typically softer than the first material, such that the forefoot support tubes 510 a-e provide the desired level of cushioning and support. In one embodiment, the first material has a durometer value of 85 Shore A, and the second material has a durometer value of 65 Shore A. In another embodiment, the first material is approximately 10-30 Shore A points higher than the second material, however, the range may vary, and alternatively the first material may be softer than the second material. If desired, the forefoot support tubes may be formed from more than two materials, for example, the walls 570 a-e may each be formed from a different material with a different durometer value in order to even more closely control the support and cushioning characteristics of the insert 160. The second material may be attached to the first material by a variety of conventional methods, such as cement, adhesive, or bonding by heating one or both of the materials.
  • [0052]
    Although not shown, in this embodiment, the midsole is similar to the midsole 18 of the first embodiment. The undersurface of the midsole may be contoured to compliment the shape of the outsole 120, heel wedge 140 and insert 160—including the forefoot support tubes 510 a-e, as in the first embodiment, such the midsole is contoured to define a plurality of support tube recesses that are adapted to closely receive the support tubes 460 a-j and the forefoot support tubes 510 a-e of the insert 160. The midsole may include a plug, similar to the plug 62 of the first embodiment. The heel wedge 140 is also similar to the heel wedge of the first embodiment, and will not be described in detail. As in the first embodiment, the heel wedge may include tube recesses 360, and a central opening 800.
  • [0053]
    The above description identifies certain approximate durometer values for the various components of the sole 10 of the illustrated embodiment. The recited values are merely exemplary and the present invention is not limited to sole constructions with the specific recited durometer values. To the contrary, the present invention should be broadly interpreted to extend to sole components having different compressibility values.
  • [0054]
    The above description is that of the 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. 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.
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US20140360052 *Sep 26, 2013Dec 11, 2014K-Swiss, Inc.Article of footwear, elements thereof, and related methods of manufacturing
USD715035Nov 13, 2013Oct 14, 2014Vibram S.P.A.Sole for footwear
USD739130Nov 13, 2013Sep 22, 2015Vibram S.P.ASole for footwear
Classifications
U.S. Classification36/28
International ClassificationA43B13/18
Cooperative ClassificationA43B7/08, A43B13/12, A43B13/181, A43B13/188, A43B7/144, A43B13/143, A43B13/186, A43B13/026, A43B13/206
European ClassificationA43B13/12, A43B13/02C, A43B13/18F5, A43B7/14A20H, A43B13/18A, A43B7/08, A43B13/18A5, A43B13/14W, A43B13/20T