Patent Document

This application claims benefit of U.S. Provisional Application No. 60/551,392, filed Mar. 9, 2003, and is a continuation-in-part of U.S. application Ser. No. 10/725,647, filed Dec. 2, 2003 now U.S. Pat. No. 7,010,867, which claims benefit of U.S. Provisional Application No. 60/491,491, filed Jul. 31, 2003. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to footwear and, more particularly, to a footwear construction and method for making the same. 
     There is an ongoing effort in the footwear industry to produce footwear that provides durability, a high level of comfort, and a degree of waterproofing. Such footwear is targeted toward individuals who stand for long periods of time on hard surfaces (e.g., concrete floors), who must travel on foot for significant distances, or who must occasionally traverse wet or damp areas or worksites. 
     Conventional footwear constructions, however, provide one of durability, comfort, or waterproofing, but usually not all three because the features required for these characteristics typically negate one another. For example, one construction known for its durability is a direct attach construction, which may be incorporated into work or hiking boots. In such a construction, a midsole, constructed of a soft, resilient material provides a uniform-depth cushion along the entire length of the shoe between the upper and the more rigid and durable outsole. This midsole is constructed with a process in which the midsole is “direct attached” to the upper, from heel to toe, in a mold. In other words, the midsole material is injected into a mold adjacent the upper and, as the material cures, it bonds to the exposed portion of the upper along the entire length of the footwear. To complete the footwear, an outsole is glued to the midsole, opposite the upper. This direct attach midsole is thus joined very securely to the upper to provide a durable shoe. 
     Although this construction is durable and aesthetically pleasing, it sometimes compromises the flexibility and comfort of the shoe due to the bond between the midsole and the upper, as well as the uniform depth, sheet-like construction of the midsole along the entire length of the footwear. Moreover, because the midsole and outsole are substantially uniform from heel to toe of the footwear, there is little or no cushion variation provided for different regions of the foot, which in turn may compromise the comfort of the shoe. Finally, the midsole, by itself, has minimal waterproofing capabilities. 
     Although different constructions exist that provide desired durability, waterproofing characteristics, or comfort, there remains an unmet need for an integrated footwear construction that provides the best of all requirements. 
     SUMMARY OF THE INVENTION 
     The aforementioned problems are overcome in the present invention, which provides a footwear construction including a membrane direct attached to an upper in the forefoot and the heel regions of the footwear to provide a waterproof barrier. The membrane includes an aesthetic bead in the forefoot region of the footwear, but not in the heel region. 
     In another embodiment, the thickness of the membrane is greater in the forefoot region than in the heel region. The membrane bead may be disposed around a perimeter of the membrane in the forefoot region adjacent the thicker portion of the membrane. 
     In another embodiment, the footwear construction may include a heel cradle to provide the desired amount of heel cushioning and stability. The heel cradle may be secured to the membrane and/or upper rearward of the thicker portion of the membrane. 
     In yet another embodiment, a water impermeable liner is secured or joined with the upper. This liner cooperates with the membrane to provide an ever greater degree of waterproofing. 
     The footwear of the present invention is manufactured by: direct attaching a membrane to an upper in the forefoot and heel region, the membrane including a thicker portion and/or an aesthetic bead in the forefoot region; joining the upper and/or membrane to an outsole; and optionally, securing a heel cradle between the upper and the outsole in the heel region. 
     The present invention provides a revolutionary footwear construction with an unparalleled combination of durability and comfort. The direct attached membrane makes the forefoot region of the footwear durable and well-supported. The membrane also renders the footwear substantially waterproof in regions and along seams previously difficult to waterproof. In the heel region of the footwear, the heel cradle provides extraordinary comfort by absorbing and returning energy produced in every step, and by offering a comfortable platform to stand on for long periods. 
     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 invention and the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is side elevational view of an article of footwear incorporating the integrated construction of the present invention; 
         FIG. 2  is a sectional view of the footwear taken along line  2 — 2  of  FIG. 1 ; 
         FIG. 3  is an exploded perspective view of the footwear; 
         FIG. 4  is a sectional view of the footwear taken along line  4 — 4  of  FIG. 2 ; 
         FIG. 5  is a sectional view of the footwear taken along line  5 — 5  of  FIG. 2 ; 
         FIG. 6  is perspective view of a membrane of the present invention; 
         FIG. 7  is a sectional view of the membrane taken along line  7 — 7  of  FIG. 6 ; 
         FIG. 8  is a sectional view of the membrane taken along line  8 — 8  of  FIG. 6 ; 
         FIG. 9  is a sectional view of the membrane taken along line  9 — 9  of  FIG. 6 ; and 
         FIG. 10  is a sectional view of a direct attach method of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A shoe incorporating the integrated construction of the present invention is shown in  FIG. 1  and generally designated  10 . For purposes of the disclosure, the present invention is described in connection with a ¾ height boot, however, the present invention is well suited for use with other types of soled footwear. 
     In general, the shoe  10  includes an upper  20  secured to an outsole  40 . A membrane  60  is direct attached to the upper  20 . The direct attach membrane shown includes a bead  62  that terminates short of the heel region of the shoe. The heel region includes a heel cradle  50  positioned between the upper  20  and the outsole  40 . Here, the upper and/or membrane may be secured to the heel cradle and/or outsole with an adhesive or cement. 
     As used herein, the term “arch region” refers generally to the portion of the shoe corresponding to the arch of the wearer&#39;s foot; the term “forefoot region” refers generally to the portion of the shoe forward of the arch region corresponding to the forefoot (e.g., the ball and the toes) of a wearer&#39;s foot; and the term “heel region” refers generally to that portion of the shoe rearward of the arch region corresponding to the heel of the wearer&#39;s foot. The forefoot region  42 , arch region  43  and heel region  44  are generally identified in  FIG. 2 , however, it is to be understood that delineation of these regions may vary depending upon the configuration of the footwear. 
     The upper  20  is generally conventional and will not be described in detail. Suffice it to say that the upper  20  includes vamp  22 , quarters  24  and backstay  26 . With reference to  FIG. 3 , the upper  20  includes a lower portion that transitions to an allowance  23 , also referred to as a peripheral allowance, which is folded inward toward the center of the footwear. This peripheral allowance, and in some cases, the lower portion of the upper, is direct attached to the membrane  60 , as described in detail below. The peripheral allowance may be secured to the insole  70 , or optionally strobel stitched to an insole and/or fabric sock liner (not shown). The upper  20  may be manufactured from leather, canvas, nylon, or other suitable materials and may include a liner (not shown) or other conventional accessories. 
     A water impermeable liner  72  is optionally secured to an interior of the upper  20 . This liner, as shown in FIGS.  2  and  4 – 5 , extends downward, toward the inwardly folded peripheral allowance  23 . In one embodiment, the liner terminates a pre-selected distance above the fold of the upper that forms the peripheral allowance. In another embodiment, the liner extends upwardly to the uppermost portion of the shoe  10 . The liner may be constructed of any material, but preferably is constructed from a water impermeable fabric or material. Suitable materials include the material sold under the trademark GORE-TEX, which is commercially available from W.L. Gore &amp; Associates, Inc. of Newark, Del., and the material sold under the trademark SYMPATEX, which is commercially available from SympaTex Technologies GmbH, Wuppertal, Germany. The liner may additionally or alternatively be constructed from a continuous layer of waterproof thermoplastic or adhesive, which coats the interior of the upper. 
     In the region defined between opposing edges of the peripheral allowance, a filler  74  may be disposed. This filler may be constructed from a conventional cushioning material, such as polyurethane. 
     The outsole  40  is manufactured from a relatively hard rubber or other sufficiently durable and wear-resistant material. The bottom  46  includes an outer surface  48  that forms the wearing surface of the outsole  40  and is contoured to the desired heel and tread pattern. The outer surface  48  may be textured to improve the traction and aesthetic appeal of the shoe. Optionally, the upper surface  47  of the outsole may be textured as desired. As shown in  FIG. 3 , the outsole  40  may include a wall  42  disposed in the arch region  43 . This wall may be substituted with a rounded barrier or eliminated altogether. It also may be disposed in the forefoot region  42  and/or the heel region  44  as desired. The wall may extend partially or completely across the outsole, and optionally terminate at the flange  49 , which extends upwardly in at least the arch region, and optionally in the heel region. The outsole  40  is secured to the membrane  60  and the heel cradle  50  with cement or adhesives, or as desired, direct attached to these components. 
     As depicted in  FIGS. 2–4 , the membrane  60  is direct attached to the peripheral allowance  23 , and where included, the filler  74  along a substantial portion of the length of the footwear. In such a direct attach construction, the material from which the membrane is constructed bonds directly to the peripheral allowance, the filler, and a lower portion of the upper. The membrane includes a plate  63 , which extends along the length of the footwear, and a bead  62 , which terminates forward of the heel region  44  without extending into the heel region. However, in some applications, the bead may extend into at least the arch region. The bead may be secured to the upper  20  substantially only in the forefoot region  42 , and may extend upwardly and around the lower periphery of the upper in the forefoot. 
     For a clean appearance in the finished footwear, the ends of the bead  62  and for the bead flange  64  are disposed behind the flange  49  of the outsole  40 . In this configuration, the ends of these components are concealed from sight. As desired, the bead  62  and bead flange  64  may extend to the wall or barrier  42  of the outsole. The membrane and its components may be manufactured from polyvinyl chloride, hard durable rubber, or other materials as desired. 
     With reference to  FIGS. 6–9 , the membrane  60  will be described in more detail. The membrane includes a plate  63 , having first  65  and second  69  sides. As shown, the first side  65  is formed against and/or bonds to the upper  20  and filler  74  when the membrane is direct attached to these components. The plate  63  is relatively planar on its upper surface, i.e. the first side, and substantially covers the opening defined between opposing peripheral allowances  23  to effectively seal with a waterproof barrier the lower portion of the upper  20 . In the forefoot region  42  of the footwear, a first flange  66  extends upwardly adjacent the upper  20 , and is secured to the upper there by direct attachment. Also in the forefoot region, the membrane includes a bead  62 . The bead extends downwardly from the insole plate a pre-selected distance. At the lowermost portion of the bead, a second flange  64 , also referred to as a bead flange, extends outwardly around a perimeter of the footwear in at least one of the forefoot region and the arch region. As desired, the bead and flanges may exist anywhere forward of the heel region. 
     The plate  63  in the region of the footwear where the bead  62  exists may be of equal or greater thickness than the region of the footwear where there is no bead. For example, as shown in FIGS.  2  and  8 – 9 , the first thickness  68  of the membrane  60  in the forefoot region  42  is greater than the second thickness  67  of the membrane  60  in the arch  43  and heel region  44 . In an alternative embodiment, the plate  63  is of a substantially equal thickness throughout the length, and the bead is a downward extension of the first flange  66  to the bead flange  64 . As desired, the membrane and all of the flanges, the bead, and the plate may be a single, unitary, integral component. 
     The membrane  60  and waterproof liner  72 , which is secured within or to the upper  20 , may cooperate to render the interior of the upper substantially waterproof. 
     As shown in  FIGS. 2–3 , the insole  70  extends along the entire length of the shoe, and may be constructed of any conventional cushioning material. In the heel region  44  and, optionally, the arch region  43 , the insole is secured via conventional means, for example, adhesives, cement, stitching or the like to the interior side of the peripheral allowance  23  of the upper. Optionally, a shank  86  of steel, plastic or other material is secured to the bottom of the insole  70  in the arch region  43  of the shoe. The shank may be secured to other components of the shoe as desired, and may overlap with the other regions, for example, the forefoot region  42  and heel region  44 . 
     With reference to  FIGS. 2 ,  3  and  5 , the shoe includes a heel cradle  50  that snugly fits in or adjacent the outsole  40 . The heel cradle  50  is preferably cup-shaped to cradle the heel of the wearer and extend upwardly around at least a portion of the wearer&#39;s heel. As shown, the heel cradle  50  is positioned substantially only in the heel region  44  and terminates at or slightly within the arch region  43 . As desired, the cradle may terminate short of the arch region or may extend beyond the arch region into the forefoot region  42 . This heel cradle is secured with adhesives or cement directly to the upper  20 . In the embodiments shown, the cradle is adhered to the peripheral allowance  23  of the upper  20  and optionally, a portion in the undersurface of the insole  70 . The heel cradle is preferably made from a low density cushioning material. In one embodiment, the heel cradle  50  is constructed from an ethylvinyl acetate (EVA) foam. The rigidity and the flexibility of the EVA foam can be varied from application to application as desired. 
     In the fully assembled footwear shown in  FIGS. 2 ,  4  and  5 , the outsole  40  is secured in the forefoot region to the membrane  60 , and to at least the heel cradle  50  in the heel region  44 . This securement may be provided by cement, adhesives or other conventional attachment means. When assembled, the rearmost portion of the bead  62 , including the bead flange  64 , is adjacent the wall  42  of the outsole, however these components may also abut against the wall as desired. In constructions where the outsole does not include a wall, the heel cradle  50  may extend forward to abut or join with the thicker portion of the membrane, or the membrane  60  may extend rearward to, abut against, or join with the heel cradle. The shank  86  and exposed portion of the underside of the insole  70  may or may not be secured to the outsole  40  as desired. 
     MANUFACTURE AND ASSEMBLY 
     Manufacture of the shoe  10  will now be described with reference to  FIGS. 3–6  and  100 . The upper  20  is manufactured using generally conventional techniques and apparatus. The desired upper material (not shown) is cut to form the upper. Although not shown, the upper may include multiple elements, such as a vamp, quarters and a back stay. If included, these pieces of the upper are fitted and sewn together. The water impermeable liner  72  is secured within the upper via adhesives or stitching that does not deteriorate the water impermeability of the liner in the desired areas. This liner is fitted to the upper so that in the finished footwear, it extends downward a sufficient distance so that the later-added membrane terminates above the lowermost portion of the liner. 
     The insole  70  is fitted on a last  100 , and the fitted upper  20  is stretched over the insole and the last. The peripheral allowance  23  is secured with a cement, adhesive or other attachment means to the underside of the insole  70 . The peripheral allowance  23  may be temporarily tacked or stapled to the last to hold the allowance in place. The filler  74  may further be cut and trimmed to fit within the void defined between opposing sides of the peripheral allowance  23 . This filler may be cemented or adhered within this void to the underside of the insole  70  and the edge of the peripheral allowance  23  as desired. 
     With the upper  20  secured to the insole  70  as desired and stretched over a last  100 , these components are prepared for a direct attach molding operation, which is shown in  FIG. 10 . The last  100  is lowered against the membrane mold  120 , which includes side molds  112  and a bottom mold  114 . Only one side mold  112  is shown in  FIG. 10 , however, it is noted that a corresponding side mold opposing the depicted side mold is included. Each side mold  112  wraps around the sides of the lasted upper  20 , and mate with one another at the front and rear of the shoe. The side molds  112  and bottom mold  114  cooperate to define a membrane cavity  130  of varying thickness but running along the length of the footwear as shown. This cavity  130  is greater in depth in the forefoot region than in the heel region. Moreover, the cavity in the forefoot portion further defines corresponding bead  162  and bead flange  164  voids that, when filled with material, form the bead and bead flange of the completed membrane. 
     It is noted here that the varying depth and deletion of the bead features in the heel region and/or arch region may be accomplished using a mold insert  140  with the mold  120 . As shown, the insert  140  rests in the membrane cavity  130 , and thereby occupies the space that would otherwise be filled by material when that material is injected into the cavity. The insert  140  further extends upwardly to cover the bead  162  and bead flange  164  voids so that material cannot enter those voids and form corresponding features in the direct attach process. The insert is generally the same shape as the heel and/or arch region of the footwear, and of a depth that is a pre-selected amount less than the depth of the membrane cavity. The insert may also include bead and flange features (not shown) so that these features can more securely interfit with the corresponding features of the side molds. 
     The side mold  112  includes a cavity side wall  115  which generally forms a side wall of the finished membrane. The bottom mold  120  may include a base wall  122 , which generally forms the bottom of the finished membrane. The base mold, or the insert  140  when included, may also include a membrane terminating wall  124 . The molds may be modified to form any portion or combination of side walls, bottom walls or other walls as desired. Optionally, the thicker region of the membrane cavity  130  in some applications may extend rearward into the arch region of the footwear, short of the heel region. In which case, the terminating wall may be positioned further rearward. 
     With the components of the mold  120 , i.e., the side molds  112  and the bottom mold  114 , positioned to form the membrane cavity  130 , the appropriate volume of material to form the membrane  60  is injected or poured through port  150  into the cavity  130 . Preferably, the mold  110  holds the upper  20  firmly enough to prevent material from exiting the mold  110  from the top of the cavity  130 . As the material  131  is introduced into the cavity  133 , it substantially fills the cavity  130  until the entire membrane  60  is formed. 
     The midsole material  131  is allowed to sufficiently cure and direct attach the membrane  60  to the upper  20 , filler  74 , and/or insole  70 . The side molds  110  are moved away from the footwear in the direction of the arrows  111 . The last  100  is moved upward in the direction indicated with the vertical arrow  101 . Any excess flashing resulting from the direct attach process may be trimmed from the membrane. With the flashing trimmed from the membrane  60 , the membrane is readied for securing the outsole  40  to it. Optionally, a shank  86  may be secured to the undersurface of the filler  74 . 
     The outsole  40  is injection molded or pour molded from a hard, durable rubber using conventional molding apparatus. Its construction may be completed before any other components of the footwear are assembled as desired. The tread pattern  48  on the lower surface  46 , the upwardly extending flanges  48 , and the wall  42  of the outsole are formed during the molding operation as integral parts of the outsole  40 . With the outsole manufactured, the heel cradle  50  is secured to the outsole  40  in the heel region  44 . In those applications where a large heel cradle is used, the cradle may also be secured to the arch region and possibly extend into the forefoot region  42  as desired. These components may be secured together with cement, adhesive or other attachment means. 
     In another step, the outsole  40  is secured with cement or adhesives to the membrane  60  along the entire length of the membrane. Preferably, the terminating end of the beaded region of the membrane aligns with the wall  42  of the outsole  40  so that it is disposed adjacent and/or abuts the wall. In one embodiment, the outsole is secured to the remainder of the footwear so that the flange  48  conceals the terminating end of the bead  62  and bead flange  64  and provides a clean appearance. In the heel region  44 , the heel cradle is adhered or cemented to the peripheral allowance  23  of the upper, and where exposed, the undersurface of the insole  70 . In the arch region, the outsole is secured to the other components of the shoe as desired. 
     With the outsole  40  secured to the membrane  60  and heel cradle  50 /upper  20 , the shoe  10  may be removed from the last. A number of conventional finishing operations may then be performed on the shoe  10 . For example, the edges of the membrane  60 , the membrane bead  62 , and bead flange  64 , and the outsole  40  are trimmed and shaped; and the upper  20  is cleaned, polished and treated as appropriate and necessary. 
     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 “the,” is not to be construed as limiting the element to the singular.

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