Cushioning system for footwear and related method of manufacture

Information

  • Patent Grant
  • 6802138
  • Patent Number
    6,802,138
  • Date Filed
    Friday, February 8, 2002
    22 years ago
  • Date Issued
    Tuesday, October 12, 2004
    20 years ago
Abstract
A footwear cushioning system including an insole platform and an insert that cooperate with one another. The insole platform includes a recess defined in the heel and/or forefoot area. The insert includes a footbed and heel and/or forefoot cushion extending from the footbed. The cushions interfit with the respective heel and/or forefoot recess of the insole platform. In a preferred embodiment, the insole platform includes a shank secured thereto, surrounding the heel recess. The insole platform is preferably shaped to define both heel and forefoot recesses and the insert includes cushions that interfit with both recesses. A midsole is secured to the insole platform and an outsole is further secured to the midsole. To assemble the cushion system, the insole platform is secured to the upper. The midsole is then secured to the insole platform. The outsole is adhered to the under surface of the midsole. The insert is fitted into the upper over the insole platform so that the heel and/or sole cushions rest within the corresponding heel and/or sole recesses of the insole platform.
Description




BACKGROUND




The present invention relates to footwear and, more particularly, to a footwear construction and a method for making the same.




In the footwear industry, there is an ongoing effort to produce footwear including a cushioning system that provides a high level of comfort for wearers. The need to produce such a cushioning system is particularly pronounced in the design of work, walking and athletic footwear, where increased cushioning is a primary objective. For example, to minimize the effects of standing and walking on hard surfaces (e.g., concrete floors), it is desirable to provide footwear that cushions the wearer's foot, particularly the heel, from the hard surface.




Many conventional cushioning systems are presently in use. In simple systems, a foam layer of varying thickness is either (1) adhered directly to an insole of a shoe before the shoe is assembled or (2) added as a footbed after the shoe is assembled. Another system incorporates a cushion disposed over the insole in a specific area, such as the heel, which typically experiences the most impact during walking. A problem with these systems, however, is that an increase in the size of the upper to accommodate the added cushion is required. This often results in a distorted looking upper or shoe, increased in size to accommodate the cushion, that is loose fitting.




One solution to these problems is disclosed in U.S. Pat. No. 6,145,220 to Johnson, Jr., which avoids adding bulky cushion layers by using a specialized heel plug or cushion disposed in a cavity perforated through shoe components in the heel area. The cavity is cut completely through the insole, midsole and outsole to accommodate the heel plug. The shank of the Johnson shoe also includes a hole corresponding to the cavity. This structure increases cushioning and maintains a low shoe profile, however, its manufacture is complicated and costly. To ensure that the different layers around the cavity remain intact, nails are used. The nails are positioned in a precise pattern to prevent them from extending into the heel cavity, where they may impede insertion of the heel plug into that cavity. After continued use, the nails holding the layers together also have a tendency to release, thereby allowing the layers to delaminate around the heel cavity. Additionally, each layer must be precisely sized and perforated to accommodate the heel plug. Furthermore, the heel plug of Johnson moves relative to the insole, the outsole and the heel of the shoe to add cushioning, but in some cases too much cushioning. As a result, the cushioning movement of the heel plug may reduce support in the shoe and make the shoe feel unstable.




Although the cushioning systems of the prior art provide cushioning, there remains a long felt and unmet need for an easily manufactured footwear construction that provides a desired level of cushioning over the life of the footwear.




SUMMARY OF THE INVENTION




The aforementioned problems are overcome in the present invention that provides an insole platform that is shaped to define an integral heel recess. A cushion insert including a heel cushion extending therefrom is disposed over the insole platform so that the heel cushion fits into and substantially fills the heel recess.




In another embodiment, the insole platform is shaped to define an integral recess in the forefoot portion, and the insert includes a corresponding sole cushion extending from it that fits into and substantially fills the sole recess. A transverse member, integral with the insole platform, separates the heel and sole recesses.




In a third embodiment, the insole platform includes a shank secured to the insole, around the heel recess. The shank preferably extends partially into the heel recess and across a portion of the transverse member to add rigidity and torsion strength to the insole platform and consequently the shoe. The shank also is preferably integrally attached to the insole platform as the insole platform is manufactured, for example, by insert molding. The shank preferably includes inclined shank walls, extending into the heel recess to center a wearer's heel in the recess.




In another embodiment, the insole platform is secured to an upper with a rib extending from the insole platform. A welt is attached around the insole platform to the rib as well. A midsole is secured to the welt, and an outsole is further secured to the welt and midsole. The outsole includes upwardly opening recesses in the forefoot and heel portions. Cushion plugs may be separately manufactured and inserted in these recesses or may be molded directly in the outsole to provide additional cushioning.




A footwear assembly of the present invention is preferably manufactured using the general steps of (a) securing an insole platform to an upper, the insole platform being shaped to define a recess; (b) securing a midsole and/or an outsole to the undersurface of the insole platform; and (c) fitting a cushioning insert into the upper positioned over the insole platform, the insert including a cushion that fits in the corresponding recess in the insole platform.




The present invention provides a novel footwear construction including a low profile cushioning system. The interaction of the recessed insole platform with the cushion of the insert in the heel eliminates the need for a heel plug extending through the insole, midsole and outsole. Without a heel plug cavity, the need for precisely perforating and nailing multiple layers of the sole assembly around the cavity is obviated. Additionally, the stability and support of the footwear is uncompromised with the added cushion. Specifically, the heel cushion of the insert interfits directly in the heel recess of the insole to avoid movement relative to multiple components of the shoe. Furthermore, the integrally molded shank around the heel recess of the insole platform provides an exceptional, torsion-resistant platform to prevent lateral strain on the ankles of a wearer and improve the rigidity of the footwear. Moreover, footwear incorporating the insole platform may be assembled without securing together all the layers of the sole—the insole, midsole, and outsole—with fasteners such as nails.




These and other objects, advantages and features of the invention will be more readily understood and appreciated by reference to the detailed description of the preferred embodiments and the drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of an article of footwear incorporating the present invention;





FIG. 2

is an exploded perspective view of the article of footwear;





FIG. 3

is a sectional view of the footwear taken along line


3





3


of

FIG. 1

;





FIG. 4

is a sectional view of the footwear taken along line


4





4


of

FIG. 1

;





FIG. 5

is a lower perspective view of an insole platform of the footwear;





FIG. 6

is a top view of the insole platform;





FIG. 7

is a sectional view of the insole platform taken along line


7


-


7


of

FIG. 6

; and





FIG. 8

is a sectional view of the insole platform taken along line


8


-


8


of FIG.


6


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




A boot constructed in accordance with a preferred embodiment of the present invention is shown in

FIGS. 1-4

and generally designated


10


. For purposes of disclosure, the present invention will be described in connection with a conventional three-quarter height boot. As will be appreciated, the present invention is well suited for use with other types of soled footwear.




Generally, the boot


10


includes an upper


12


, insert


80


, insole platform


40


, midsole


50


and outsole


60


. The upper


12


is secured to the insole platform


40


, which is secured to the midsole


50


. The insert


80


fits over the insole platform


40


. The midsole


50


further is secured to the outsole


60


. The welt


30


is attached to and interconnects the upper


12


, the insole platform


40


and the midsole


50


.




The upper


12


is conventional and will only be described briefly here. Upper


12


includes a quarter


29


and a vamp


28


. The upper


12


terminates in the lower peripheral edge


26


, which is attached to the insole platform


40


through the welt


30


as described in detail below. The upper


12


is preferably manufactured from leather, canvas, nylon or other suitable materials, and may include a liner (not shown) or other conventional accessories.




As best shown in

FIGS. 3 and 4

, the welt


30


extends entirely around the boot


10


to interconnect the upper


12


, the insole platform


40


and the midsole


50


. The welt


30


is generally conventional, including a generally horizontal base portion


32


with an upwardly extending upper rib


34


located toward the center of the base portion


32


. The outer surface of the upper rib


34


is rounded to, among other things, reduce the profile of the welt


30


. The inner surface of the horizontal base portion


32


is generally tapered in cross section and is of sufficient size to receive staples, stitching or other fastening elements. The horizontal base portion


32


defines an upwardly opening stitch grove


38


that extends around the welt


30


near its outer edge. The stitch grove


38


is adapted to receive stitching


74


that interconnects the midsole


50


and welt


30


as described in more detail below. Optionally, the stitching


74


and stitch grove


38


may be absent from the footwear as desired, with only stitching


74


connecting the insole platform


40


and upper


12


to the midsole


50


.




The insert


80


generally includes heel cushion, or element,


86


and sole cushion


88


extending from the insert base


82


. The insert base


82


is configured to outline the shape of a foot and cradle the foot. The insert base may include a sock liner


84


attached to it and vents


87


to improve the circulation of air in the shoe


10


. The heel cushion


86


and sole cushion


88


are designed to interfit the heel recess


46


and sole recess


48


respectively as described in further detail below. As shown, the heel cushion


86


includes multiple triangular-shaped ribs


85


. These ribs


85


are preferably forwardly inclined from the vertical. The sole cushion


88


includes similar ribs, but rearwardly inclined from the vertical.




The insole platform


40


includes a base or plate


42


with a downwardly extending rib


44


. The insole base


42


is generally planar and corresponds in shape with an outline of a foot. The insole rib


44


extends downwardly and around the insole base


42


at or near its outer edge or periphery. The insole rib is of sufficient size to receive staples, stitching or other fastening elements. The insole rib


44


interconnects the insole plate


40


to the upper


12


, the welt


30


, and the midsole.




The insole base


40


defines a heel recess


46


extending downwardly the heel area of the shoe


10


. The heel recess is bounded by a bottom wall


47


and side wall


45


. Additional side walls may be included as desired to alter the configuration of the recess. The insole base optionally includes a sole recess


48


in the forefoot portion of the shoe. The sole recess is bounded by a bottom wall


43


and side walls


49


, which may vary in number depending on the desired configuration of the sole recess. The heel recess


46


and sole recess


48


extend downwardly from the insole base a depth substantially equal to the insole rib


44


, or any other depth as desired.




With further reference to

FIGS. 3

,


5


and


7


, the sole recess


48


and heel recess


46


are separated by a transverse member


75


. The transverse member includes a bottom surface


77


that is substantially in the same plane as the lower surfaces of the bottom walls


47


,


49


of the heel


46


and sole


48


recesses. The transverse member is preferably of sufficient thickness to add torsion strength and rigidity to the insole platform. As shown, the transverse member extends a portion of the depth between the lower surfaces of the bottom walls


47


,


49


and the insole base


42


, with the remainder of the depth occupied by the shank


70


as explained in more detail below.




As best shown in

FIGS. 5 and 7

, the transverse member


75


extends across a center portion of the width of the foot between the insole rib


44


on opposite sides of the insole platform, however, the transverse member optionally may extend and connect the insole rib on opposite sides of the insole platform as desired. The transverse member is preferably an integrally molded part of the insole platform, but may also be interconnected to the insole platform in a conventional manner.




The insole platform


40


preferably is constructed from polyvinyl chloride, but other materials, such as polymers, rubber or other synthetic materials alternatively may used. Additionally, the surfaces of all or selected components of the insole platform may be textured to improve the adhesion of cements and adhesives thereto.




As best shown in

FIGS. 6

,


7


and


8


, the footwear


10


also includes a shank


70


, which is included in the insole platform


40


. The shank


70


extends across the transverse member


75


, preferably across the width of the insole platform. Although depicted as covering the entire transverse member, the shank may cover only a portion of the transverse member between the heel recess


46


and sole recess


48


as desired. The shank is preferably of a unitary construction that surrounds the heel recess to add torsion strength in the heel region and/or rigidity to the footwear


10


.




As shown in

FIGS. 4 and 8

, the shank


70


may include shank recess walls


79


which extend down the side walls


45


of the heel recess


46


, terminating at or near the heel recess bottom wall


47


. The shank recess walls


79


and sidewalls


45


of the recess are preferably inclined from the vertical as shown to center a wearer's heel as the wearer applies a downward force on the insert


80


, forcing the heel cushion


86


into the heel recess


46


.




The shank may also include mold cores


78


and/or shank cores


41


that enhance attachment of the shank to the insole platform


40


. For example, the mold cores


78


allow the material from which the insole platform


40


is molded to seep into them during molding. When the insole platform material cures, the interaction of the insole platform material and the mold cores


78


provide a mechanical bond between the shank


70


and the insole platform


40


. This mechanical bond is helpful where the insole platform material and shank material do not bond well to one another. As will be appreciated, where the insole platform material and the shank material bond well, the cores may be reduced in number or eliminated. Additionally, the shank may include positioning pins


73


to assist locating the shank


70


on the insole platform


40


and hold the two in fixed relation.




The shank


70


is preferably constructed from polystyrene, but may be constructed from other plastic, metal or synthetic materials that may be secured to the insole platform


40


to add rigidity to the shoe


10


as desired.




With reference to

FIGS. 2

,


3


and


5


, the sole recess


48


terminates short of the front of the insole platform


40


to define a toe cushion recess


69


bounded in part by a portion of the insole rib


44


and a side wall


43


of the sole recess


48


. A toe cushion


61


preferably is disposed in the toe cushion recess


69


to add cushioning in the toe region of the shoe


10


. The toe cushion as shown includes a plurality of transverse ribs, preferably forwardly inclined from the vertical and extending across a the width of the toe cushion


61


. The transverse ribs may be rearwardly inclined from the vertical if desired. Furthermore, the toe cushion


61


may be of uniform, solid construction or a dual/multiple density construction.





FIGS. 3 and 4

show the interconnecting of the upper


12


to the insole platform


40


and the interconnecting of the insole platform


40


, the upper


12


, and the welt


30


to the midsole


50


. The upper


12


is secured to the insole platform rib


44


with staples


27


. As will be appreciated, other fastening means may be used such as stitching and adhesives may be used. The stitching


72


interconnects the insole platform rib


44


to the upper


12


, welt


30


and midsole


50


. Additional stitching


74


within groove


38


also connects the welt


30


to the midsole


60


. The insole platform


40


may be further secured to the midsole


50


with adhesive as desired.




The midsole


50


generally includes a midsole base


52


which is generally of a planar or sheet construction and corresponds in shape with the outline of the foot. The midsole base optionally includes a plurality of midsole apertures


54


to enhance air flow out from outsole


60


and increase cushioning. The midsole


50


preferably is constructed from rubber, plastic or other synthetic or natural materials. The midsole is further secured to the outsole


60


with a suitable adhesive or other fastening means such as stitching.




The outsole


60


generally includes a outer surface


62


, outsole top surface


67


, heel cavity


66


and sole cavity


68


. The outer surface


62


may be contoured to define the desired heel and tread patterns. The outer surface


62


may also be textured as desired to improve the traction and esthetic appeal of the footwear. The outsole


60


is preferably manufactured from a relatively hard rubber or other sufficiently durable and wear-resistant material, for example, polyurethane, polyvinyl chloride, or thermoplastic rubber.




The heel cavity


66


and sole cavity


68


have disposed therein heel pad


65


and sole pad


63


positioned therein to increase the cushion characteristics of the outsole


60


. The sole pad


63


and heel pad


65


are preferably the same depth as the sole cavity


68


and heel cavity


66


respectively. The sole pad


63


is shown as including a uniform solid construction, but may include other cushioning structure, for example transverse ribs like those of the toe cushion pad described above. The heel pad


65


preferably includes transverse ribs configured to incline rearwardly from the vertical. As will be appreciated, the heel pad may be of uniform solid or other construction as desired.




The pads in the heel and sole may be of a variety of constructions, sizes and materials. For example, the pads may be integrally molded into the outsole


60


as part of a dual-density outsole. The outsole pads may be of varying sizes as desired.




The insert


80


, toe cushion


61


, outsole heel


65


and sole


63


pads are constructed from ethyl vinyl acetate (EVA), and alternatively polyurethane, or other conventional cushioning materials.




Manufacture and Assembly




The boot


10


is manufactured using generally conventional machinery. Below is a description of the manufacture of each of the components of the boot


10


followed by a description of the assembly of the components to form the boot


10


.




The upper


12


is manufactured using generally conventional techniques and apparatus. The desired upper material (not shown) is cut to form the various elements of the upper, including the vamp


28


and quarter


29


. The elements of the upper are then fitted and sewn together using conventional methods and apparatus. A lining (not shown) may be sewn within the upper during the fitting step.




The insert


80


is manufactured using conventional molding techniques and apparatus, for example, the insert may be injection or pour molded from EVA or foam. The welt


30


is manufactured using conventional techniques and apparatus. For example, the welt


30


can be extruded from hard durable rubber.




The insole platform


40


is manufactured using injection mold techniques. A conventional two-part mold (not shown) including interior surfaces corresponding to the components of the insole platform


40


is provided. A pre-molded shank


70


is disposed in one of the mold parts adjacent in the heel region. As noted above, the shank


70


preferably includes mold cores


78


, positioning pins


73


and shank cores


41


. The mold parts are closed and the insole platform material is introduced into the mold cavity (not shown). As the material is introduced, it seeps into the mold cores


78


, and shank cores


41


and forms around the positioning pins


73


to create a mechanical bond between the shank


70


and molded insole platform


40


. The completed insole platform


40


with attached shank


70


is removed from the mold.




The midsole


50


is manufactured using conventional techniques and apparatus. For example, the midsole is die cut from a sheet of rubber or other material in the shape of a foot.




The outsole


60


preferably is injection or pour molded to form a flexible yet durable outsole using conventional molding apparatus. Preferably, the wear surface


62


, sole cavity


68


and heel cavity


66


are all formed during the molding operation to form an integral part of the outsole


60


. Pre-manufactured heel pad


65


and sole pad


63


are positioned in the respective heel cavity


66


and sole cavity


68


, and may be cemented, fused, or otherwise secured therein as desired. Optionally, the outsole


60


may be dual-density molded, with the regions generally corresponding to the heel cavity


66


and sole cavity


68


molded with a material of a different density, preferably less dense, than the remainder of the outsole.




To begin assembly of components to form the boot


10


, the fitted upper


12


is stretched over a last (not shown). The insole platform


40


is placed within the lower peripheral edge


26


of the upper using conventional apparatus and techniques. The insole platform rib


44


is stapled directly to the lower peripheral edge


26


with staples


27


. Alternatively, insole rib


44


can be sewn, glued or otherwise attached to the upper


12


in a conventional manner.




With the upper


12


is lasted to the insole platform


40


, the welt


30


and midsole


50


are attached to the upper


12


and insole platform


40


. Specifically, the inner surface of the horizontal base portion


32


and the midsole


50


are stitched around the peripheral edge


26


of the upper


12


and the insole platform rib


44


using conventional apparatus and techniques. This rib stitch


72


preferably extends through the horizontal base portion


32


, the lower peripheral edge


26


of the upper


12


, the insole rib


44


and the midsole


50


. Another welt stitch


74


, positioned within stitch groove


38


further secures the horizontal base portion to the midsole


50


. If desired, the insole platform


40


or other sole component can be cemented to the midsole


50


using conventional adhesive, cementing or fusing techniques. Preferably, the toe cushion


61


is positioned in the toe cushion cavity


69


before the midsole is secured to the upper and insole platform. The toe cushion may be loose, or cemented, or otherwise secured in a conventional manner to the insole platform cushion cavity and midsole as desired.




The outsole


60


is cemented, fused or otherwise secured to the midsole


50


using conventional techniques and apparatus. With the sole assembly and components secured to the upper, the insert


80


is positioned in the footwear


10


, over the insole platform so that the sole


88


and heel


86


cushions interfit with the sole


48


and heel


46


recesses respectively. The insert may be cemented or otherwise secured to the insole platform as desired.




Finally, a number of conventional finishing operations are performed on the boot


10


. For example, the edge of the outsole


60


is trimmed and shaped; the upper


12


is cleaned, polished and treated as appropriate and necessary; and the laces are inserted in the eyelets.




The above descriptions are those of the preferred 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 references 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.



Claims
  • 1. An insole platform for a welted article of footwear comprising:an insole platform formed in the shape of a foot, said insole platform shaped to define an upwardly opening recess including a bottom wall; a rib extending downwardly from said insole platform to define a downwardly opening platform recess, said rib adapted to affix a welt to said insole platform wherein said upwardly opening recess at least partially occupies a space within said downwardly opening platform recess.
  • 2. The insole platform of claim 1 comprising a shank secured to said insole platform, wherein said shank extends substantially around said recess.
  • 3. The insole platform of claim 1 comprising an insert including a footbed and a downwardly extending cushion element, said cushion element fitted at least partially within said recess.
  • 4. The insole platform of claim 3 wherein said recess is formed in at least one of a heel and a forefoot of the foot of a wearer.
  • 5. The insole platform of claim 2 wherein said shank is formed of polystyrene and said insole platform is formed of polyvinyl chloride.
  • 6. The insole platform of claim 1 wherein said recess includes at least one side wall connected to said bottom wall.
  • 7. The insole platform of claim 2 wherein said shank includes at least one shank wall extending along at least a portion of said side wall toward said bottom wall.
  • 8. The insole platform of claim 7 wherein said shank wall and said side wall are inclined from vertical to center a wearer's foot within said recess.
  • 9. A cushioning system for footwear comprising:an insole platform including an insole plate corresponding to the shape of a human foot and having an underside, said insole plate defining a first recess bounded by a bottom wall, said insole platform further including an insole rib extending downwardly from said insole plate to define a second recess, said second recess at least partially surrounding said first recess on said underside; an insert corresponding to the shape of a human foot including a cushion element extending from and positioned over said insole platform so that said cushion element fits substantially within said recess.
  • 10. A sole assembly for a welted article of footwear comprising: an outsole including an upper surface;a midsole secured to said outsole, said midsole of a sheet construction substantially covering said upper surface; an insole platform secured to said midsole, said insole platform including a downwardly extending rib which defines a downwardly opening recess, said insole platform defining an upwardly opening recess bounded by one or more side walls and a bottom, at least a portion of said bottom in a position that is at least one of in and below said downwardly opening recess; and an insert including a footbed and a cushion extending from said footbed and interfit with said upwardly opening recess.
  • 11. The sole assembly of claim 10 wherein said insole platform includes at least one of a heel and a forefoot, and wherein said upwardly opening recess is formed in at least one of the heel and the forefoot.
  • 12. The sole assembly of claim 11 wherein said insert includes a heel cushion extending from said footbed and interfit within said upwardly opening recess formed in the heel.
  • 13. The sole assembly of claim 11 wherein said insert includes at least one of a heel cushion and a forefoot cushion, said heel cushion including a plurality of downwardly extending ribs being forwardly inclined from the vertical, said forefoot cushion including a plurality of downwardly extending ribs and being rearwardly inclined from the vertical.
  • 14. The sole assembly of claim 11 wherein said insert includes at least one of a heel cushion and a forefoot cushion of a solid cushion construction.
  • 15. The sole assembly of claim 11 comprising a shank integrally secured to said insole platform around said upwardly opening recess formed in the heel.
  • 16. The sole assembly of claim 15 wherein said shank includes at least one shank wall that extends adjacent said one or more side walls.
  • 17. A sole assembly for a welted article of footwear comprising:an outsole including an upper surface; a midsole secured to said outsole, said midsole of a sheet construction substantially covering said upper surface; an insole platform secured to said midsole, said insole platform defining a recess bounded by one or more side walls and a bottom; an insert including a footbed and a cushion extending from said footbed and interfit with said recess; and wherein said outsole defines a cavity including at least one of a pad positioned in said cavity and a plug molded in said cavity.
  • 18. A method for manufacturing a sole assembly for welted footwear comprising:providing an insole platform including an insole heel portion, an insole forefoot portion, and an insole plate, said insole plate including a side wall extending downwardly from said insole plate on a first side of said insole plate and a bottom wall, said side wall and said bottom wall cooperating to define an upwardly opening recess below said insole plate on said first side, the insole platform further including a rib extending downwardly from said insole plate on said first side, said rib adapted to affix the insole platform to a welt; securing the rib to a midsole; and securing at least one of the midsole and the insole platform to an outsole, the outsole including an outsole heel portion.
  • 19. A method for manufacturing a sole assembly for welted footwear comprising:providing an insole platform including an insole heel portion, an insole forefoot portion, and an insole plate defining an upwardly opening recess bounded by a bottom wall and at least one side wall, the insole platform further including a rib extending therefrom for affixing the insole platform to a welt; securing the rib to a midsole of a sheet construction; securing at least one of the midsole and the insole platform to an outsole, the outsole including an outsole heel portion; and wherein the outsole defines a heel cavity in the outsole heel portion, the heel cavity including at least one of a heel pad positioned in said heel cavity and a heel plug molded in said heel cavity.
  • 20. The method of claim 19 wherein the midsole is substantially void of any perforations that correspond to the upwardly opening recess in the insole platform.
  • 21. The method of claim 19 comprising disposing an insert over the insole platform the insert including a cushion, wherein the cushion is disposed in the recess.
  • 22. The method of claim 18 wherein a shank is secured to the insole plate, the shank extending around the recess.
  • 23. The method of claim 22 wherein insole platform is molded from polyvinyl chloride and the shank is molded from polystyrene.
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