Abstract:
A shoe design is expandable along its lengthwise axis utilizing one or both of a sliding outsole configuration or a sliding insole configuration. In one embodiment, the shoe has a multipart upper and/or multipart outsole interconnected by an expandable section made of a stretchable material which surrounds a pair of insole members arranged in an overlapping manner but allowed to move freely relative to one another as the expandable section expands or contracts. In one embodiment, the outsole of the shoe is slidably received within the heel of the shoe so as to allow for lengthwise expansion of the outsole as the upper portion of the shoe expands.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of priority to U.S. Provisional Application No. 61/680,515, filed on Aug. 7, 2012, entitled EXPANDABLE SHOE WITH FLOATING OUTSOLE, the entire subject matter of which is incorporated herein by this reference for all purposes. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a shoe that expands and contracts along a lengthwise direction of the shoe, 
       BACKGROUND 
       [0003]    The construction techniques and materials utilized in modern footwear and shoes have enabled most shoes to outlive the wearer&#39;s individual needs for shoes of that size. Such needs may occur over an extended length of time, such as a child&#39;s gradual outgrowth of their current shoes, or on a daily basis, such as the need for a larger size shoe due to swelling of the feet, water retention, gout, arthritis, etc. 
         [0004]    Certain prior art designs of expandable shoes either add significantly to the manufacturing costs of the shoe or adversely affect the aesthetics or comfort of the shoe or even require specific reconfiguration of the shoe to achieve discrete incremental increases in the lengthwise size of the shoe. 
         [0005]    Accordingly, a need exists for a shoe design in which the shoe is expandable and contractible along the lengthwise axis of the shoe to accommodate either temporary or gradual changes in the foot size of the wearer. 
         [0006]    A further need exists for a shoe design in which the shoe is continuously expandable and contractible along the lengthwise axis of the shoe. 
         [0007]    Yet another need exists for a shoe design in which the shoe is expandable and contractible in a manner which does not adversely affect the aesthetics or comfort of the shoe or require specific reconfiguration of the shoe to achieve expansion or contraction of the shoe. 
         [0008]    U.S. Pat. No. 6,374,515 discloses a shoe with an insole configuration which enables expansion of the shoe&#39;s upper portions. The floating insole has a section that spans a gap between separate front and heel outsole parts. Although the insole does provide some degree of protection from pebbles rocks or other debris on the walking surface, the intermediate gap portion of the shoe is exposed. 
         [0009]    Accordingly, need exists for expandable shoe that adequately protects the under surface of wearer&#39;s foot, while still allowing for expansion of the shoe upper. 
         [0010]    Further need exists for an expendable shoe that provides a protective outsole over the entire length of the shoe while still allowing for expansion of the shoe upper. 
       SUMMARY 
       [0011]    A shoe design is expandable along its lengthwise axis utilizing one or both of a sliding outsole configuration or a sliding insole configuration. In one embodiment, the shoe has a multipart upper and/or multipart outsole interconnected by an expandable section made of a stretchable material which surrounds a pair of insole members arranged in an overlapping manner, but allowed to move freely relative to one another as the expandable section expands or contracts. In another embodiment, the shoe has an outsole slidably received within the heel of the shoe in addition to the expandable section and/or overlapping insole members. 
         [0012]    More specifically, disclosed herein is a shoe design in which a shoe, having an upper portion that is expandable at least along a length of the shoe, further includes a multipart insole slidably disposed within the upper portion of the shoe so as to allow for lengthwise expansion of the insole as the upper portion of the shoe expands. In various embodiments, the upper portion itself may be made of an expandable material or may comprise front and back portions interconnected by an expandable segment. The outsole of the shoe may also have front and back portions or may utilize the sliding outsole design as described herein. In the contemplated embodiments, at least two insole pieces slide relative to each other, with each piece being attached to either a portion of the shoe upper or shoe outsole. In various disclosed embodiments, a front insole portion may be disposed either above or beneath a rear insole portion to allow motion relative thereto as the shoe expands lengthwise. 
         [0013]    According to another aspect of the disclosure, an insole for use in an expandable shoe comprises a front insole portion and a back insole portion disposed adjacent one another but not mechanically coupled so as to allow relative sliding motion therebetween when the portion of the shoe to which the insole portion is attached moves along a lengthwise axis of the shoe, 
         [0014]    Further disclosed herein is a shoe design in which a shoe, having an upper portion that is expandable at least along a length of the shoe, further includes an outsole slidably received within the heel of the shoe so as to allow for lengthwise expansion of the outsole as the upper portion of the shoe expands. In one embodiment, the shoe comprises a heel having a top surface and a breast surface, the heel defining a cavity that is open on one of the breast surface and top of the heel. The outsole extends from a front of the shoe upper to the heel, with a rear portion of the outsole being received within the cavity. An optional shield element, having a front portion connected to the outsole and a rear portion connected to heel, preventing water and dirt from entering the heel cavity. In other embodiments, the sides of the shield are connected to the shoe upper in manner that does not inhibit the longitudinal expansion of the upper. For example, the connection of the sides of the shield to the upper may be accomplished by a cross-stitch or a zig-zag stitch. 
         [0015]    According to another aspect of the disclosure, a shoe comprises an expandable upper having first and second ends, and an outsole having first and second ends, wherein a first end of the outsole is fixed relative to an end of the expandable upper and a second end of the outsole is unattached to the expandable upper and floats relative to the expandable upper in both expanded or contracted states. 
         [0016]    According to yet another aspect of the invention, a shoe comprises an expandable upper, a heel securable to the expandable upper and defining a cavity at least partially extending through the heel, and an out sole having a first end movably disposed within the heel cavity and a second end fixed relative to an end of the expandable upper. 
         [0017]    According to still another aspect of the invention, an expandable shoe comprises a front upper portion, a rear upper portion, a front outsole portion, and a rear outsole portion, an expandable portion between the front upper portion and the rear upper portion and between the front outsole portion and the rear outsole portion, a first insole on the front outsole portion, and a second insole on the first insole and the rear outsole portion, the rear insole being sized substantially the same as a foot contour, wherein the first insole is movable relative to a front portion of the second insole along a lengthwise direction of the expandable shoe. In one embodiment, the first insole is sized substantially the same as the front outsole. The rear outsole portion comprises a heel. The first insole is securely coupled to one or both of the front upper portion and the front outsole portion. A rear portion of the second insole is securely coupled to one or both of the rear upper portion and the rear outsole portion. The first insole frictionally contacts the front portion of the second insole. The expandable portion is made of a stretchable material. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The disclosed shoe apparatus will be more fully understood when read in conjunction with the drawings where like reference characters denote similar elements throughout the several views: 
           [0019]      FIG. 1  is a side view of a shoe having a sliding insole and a sliding outsole in accordance with the disclosure; 
           [0020]      FIG. 2  is a bottom view of an embodiment of the sliding outsole and heel configuration in accordance with the disclosure; 
           [0021]      FIG. 3A  is a front view of an embodiment of a heel useful with a sliding outsole in accordance with the disclosure; 
           [0022]      FIG. 3B  is a front view of the he&amp; and heel seat useful with a sliding outsole in accordance with the disclosure; 
           [0023]      FIG. 4  is a top view of the heel of  FIG. 3A ; 
           [0024]      FIG. 5  is a top view of an outsole in relation to the heel of  FIGS. 3A and 3B  in accordance with the disclosure; 
           [0025]      FIG. 6  is an exploded, perspective view of an embodiment of the sliding outsole in accordance with the disclosure; 
           [0026]      FIG. 7  is a lateral, cross-sectional view of the sliding outsole embodiment of  FIG. 6 , as seen along the line XII-XII. 
           [0027]      FIG. 8  is a side view of a shoe having a sliding insole in accordance with the disclosure; 
           [0028]      FIGS. 9A and 9B  are exploded, cross-sectional views of sliding insole of  FIG. 8  in normal and expanded configurations, respectively, relative to the expandable upper and outsole in accordance with the disclosure; 
           [0029]      FIG. 10  is a side view of a shoe having a sliding insole in accordance with the disclosure; 
           [0030]      FIG. 11  is partial views of sliding insole of  FIG. 10  with the perimeter of the shoe upper illustrated in phantom in accordance with the disclosure; and 
           [0031]      FIGS. 12A and 12B  are exploded, cross-sectional views of sliding insole in normal and expanded configurations, respectively, relative to the expandable upper and outsole in accordance with the disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    Sliding Outsole 
         [0033]    Referring now to  FIGS. 1-9B , a shoe  100 A according to an illustrative embodiment, as shown in  FIGS. 1-5 , comprises a shoe upper  12  and a sliding outsole configuration  10 . The shoe upper  12  is expandable and may include at least an expandable shank area made of neoprene, GORETEX®, or other known or hereafter developed expandable material. Alternatively, the entire upper  12  may be made of an expandable material. The expandability of the shoe accommodates temporary or permanent increases in the size of the wearer&#39;s foot. 
         [0034]    In one embodiment, the shoe  100 A uses an expandable goring or stretch leather in the toe box so as to allow widthwise expansion in addition to the lengthwise expandability. In an alternative embodiment, the shoe upper  12  is made of a flexible material, such as leather, suede, etc., with a V-cut vamp formed thereon. An expandable material  22 , such as neoprene, GORETEX®, or other known or hereafter developed materials, may be formed at the V-cut vamp of shoe upper  12 . The shoe upper  12  is thus partially expandable widthwise for shoe  100 A to accommodate the variable size of the wearer&#39;s foot. 
         [0035]    Outsole configuration  10  comprises an outsole  14  and a heel  16 . Outsole  14  comprises a heel portion  14   a  and a toe portion  14   b,  as shown in  FIG. 5 . In various embodiments, outsole  14  may be formed of a flexible, yet rigid material, such as any natural or synthetic plastic resins, natural or synthetic rubber, leather, or other known or hereafter developed material utilized for shoe outer soles. Outsole  14  may be formed of a homogeneous material or may have multiple materials or patterns integrally formed therein, particularly to facilitate traction in the toe region  14   b.  The shape of outsole  14  may be similar or dissimilar to that illustrated in the Figures and may be any of symmetrical, non-symmetrical or irregular, at the discretion of the designer. 
         [0036]    As shown in  FIGS. 3A ,  3 B, and  4 , the heel  16  of outsole configuration  10  comprises a main body portion having a cavity  16   b  opening to either a top surface  16   c  or a breast surface  16   a,  i.e,, front surface, thereof. Rear portion  14   a  of outsole  14  is slidably received and movable within cavity  16   b,  depending upon the unexpanded or expanded length of upper  12  of shoe  100 A, Outsole  14  may be attached to the shoe upper  12  proximate portion  14   b  thereof while portion  14   a  thereof is free to float in and out of cavity  1  ea of heel  16 . In the illustrative embodiment, portion  14   b  of outsole  14  is detached from the upper  12  in a shank area  20  of the shoe  100 A, as illustrated in  FIG. 1 , allowing the outsole  14  to move relative to the heel  16  as the upper  12  expands along the lengthwise axis of the shoe extending from the toe to the heel of the shoe. 
         [0037]    As illustrated in Fig,  3 B, an optional heel seat  16   e  may cover all or a portion of cavity  16   b  and may be disposed intermediate on top surface  16   c  of heel  16  and a portion of the upper  12  of shoe  100 A. As illustrated in the embodiment of  FIGS. 6 and 7 , heel seat  16   e  may also be integrally formed with the body of heel  16 , or, alternatively, may be eliminated altogether with its functionality performed by a portion of upper  12 . 
         [0038]    To prevent water, dirt, and other debris from entering the cavity  16   b  of heel  16 , an optional shield  18  is disposed proximate the breast  16   a  of the heel  16  and outsole  14  in the shank area  20  proximate the entrance of cavity  16   b,  where outsole portion  14   a  is slidably received within heel  16 . A front portion of shield  18  may be secured to the bottom and or sides of outsole  14  by any known attachment mechanism including, but not limited to, any of stitching, mechanical fasteners, various natural or synthetic adhesives, or thermal fusing or bonding, etc., depending upon the structural composition of both the shield material and outsole  14 . A rear portion shield  18  may be secured to breast surface  16   a  of the heel  16  utilizing similar methods, In one embodiment, the side edges of shield  18  are stitched to the shoe upper  12  in the area between the front of the shield  18  and the heel  16 . Such stitching may be implemented with a zig-zag stitch or cross-stitch pattern that does not inhibit the extension or expansion of the upper  12  in the area of the shank  20 . In various embodiments, shield  18  may comprise natural or synthetic rubber, a natural or synthetic resin, such as polyurethane or polyester, a paper or fabric impregnated any of the foregoing, or any other material that is waterproof and is expandable to allow for the expansion or extension of the upper  12  in the area of the shank  20 . To accommodate the expansion or extension of the upper  12 , shield  18  may include an accordion pleat formed therein. In one embodiment, to anchor the rear end of the shield  18  to the heel  16 , a rear end portion of shield  18  may be disposed and secured intermediate top lift  16   d  and the main body of the heel  16 . 
         [0039]      FIGS. 6 and 7  show an embodiment in which the cavity  16   b  opens to breast surface  16   a  of the heel  16 , In this embodiment, the shield  18 ′ is a collared sleeve through which the rear portion  14   a  of the outsole  14  is movably received. A front part of the shield  18 ′ is cemented around the entire circumference to the outsole portion  14 . The rear side of the shield  18 ′ is secured, using any of the previously described processes or techniques, to breast surface  16   a  of heel  16  to create a seal around the cavity  16   b.  For this purpose, the rear side of the shield  18 ′ is flange or collar. Although not shown in  FIGS. 6 and 7 , the shield  18 ′ may also include an accordion pleat to facilitate extension. During assembly, shield  18 ′ may is secured to outsole  14  at a position along counsel  14  which will allow for expansion of the accordion pleat shield  18  simultaneously with expansion of upper  12  shoe  100 , once shield  18 ′ is secured to heel  16 . In other embodiments, all or a portion of shield  18 ′ may be integrally formed with heel  16 . 
         [0040]    Sliding Insole 
         [0041]    Referring to  FIGS. 8 through 12B , shoes  100 B,  100 C and  100 D according to illustrative embodiments, each comprise a shoe upper  12  and outsole  14 . The shoe upper  12  may comprise a front upper portion  12 A and a rear upper portion  12 B interconnected by an expandable portion  15 , illustrated with crosshatching for clarity. Front upper portion  12 A and a rear upper portion  12 B may comprise materials as previously described with reference to shoe  100 A. Expandable portion  15  comprise any of neoprene, GORETEXO, or other known or hereafter developed expandable material. Alternatively, the entire upper  12  of shoe  100 B or  100 C may comprise an expandable material, such as those described herein. In addition, any of shoes  100 C- 100 D may comprise an upper formed from straps or noncontiguous sections, similar to a sandal or other casual shoe allowing the wearer&#39;s foot to be partially exposed 
         [0042]    As illustrated in  FIGS. 9A and 9B , outsole  10  may comprise an outsole  14  and a heel  16  substantially as described with reference to  FIGS. 1 through 7 . In the embodiments described with reference to  FIGS. 10 through 126 , outsole  14  may comprise a front outsole portion  14 A and a rear outsole portion  14 B. One or both of outsole portions  14 A or  14 B may comprise a flexible, yet rigid material, such as any natural or synthetic plastic resins, natural or synthetic rubber, leather, or other known or hereafter developed material utilized for shoe outer soles and may be formed of a homogeneous material or may have multiple materials or patterns integrally formed therein, particularly to facilitate traction, The shape of outsole  14  may be similar or dissimilar to that illustrated in the Figures and may be any of symmetrical, non-symmetrical or irregular, at the discretion of the designer. Further, front outsole portion  14 A and a rear outsole portion  14 B may be similar or dissimilar from each other in both shape and/or material composition. 
         [0043]    As illustrated in  FIGS. 10 through 12B , front outsole portion  14 A and a rear outsole portion  14 B are separated by a space or gap but are movably coupled together by expandable portion  15  to enable expansion and contraction of outsole portion  14 A and a rear outsole portion  14 B relative to each other along a lengthwise axis of shoes  100 C- 100 D. 
         [0044]    Shoes  1006 - 100 D additionally comprise a sliding insole  25 , which, in one embodiment, comprises a front insole portion  25 A and a rear insole portion  25 B which at least partially overlap one another in both contracted and expanded states of shoe  100 B or  100 C. Front insole portion  25 A and rear insole portion  25 B can be made of leather, synthetic material, rubber, plastic, or any other known or hereafter developed material suitable for use as a shoe insole. Note that front insole portion  25 A and rear insole portion  25 B do not have to comprise the same material and may have dissimilar shapes. 
         [0045]    Front insole portion  25 A and a rear insole portion  25 B are not mechanically coupled or attached directly to each other whether by a rigid, semi-rigid or stretchable member. Instead, an end of rear insole portion  25 B proximate the region in which they overlap is free and unsecured to allow for relative sliding motion therebetween along the lengthwise axis of shoe  100 . This arrangement enables longitudinal extension or contraction of shoe  100 B or  100 C to accommodate temporary swelling of a wearer&#39;s foot and/or to accommodate foot growth. 
         [0046]    In one embodiment, as shown in  FIGS. 9A-9B  and  11 , insole portion  25 B is formed on heal  16  and outsole  14 , overlapping a substantial portion of insole portion  25 A, for receiving a wearer&#39;s foot. As shown in  FIG. 9A  when shoe  100 B is in a contracted state, rear insole portion  25 B extends from heel  16  to the front end of outsole  14 , covering the entire upper portion of front insole portion  25 A. As shown in  FIGS. 9B and 12B  and, when shoes  100 B and  100 C are in an extended state, rear insole portion  25 B is pulled to slide over the top of insole portion  25 A in a rearward direction, thereby exposing a part of the upper portion of insole portion  25 A at the toe region of shoes  100 A and  100 B. In  FIG. 11 , the amount of movement of insole portion  25 B is illustrated by line segment X-X′, although not shown to scale. 
         [0047]    One or both of front insole portion  25 A and a rear insole portion  25 B may be attached to either upper  12  or outsole  14 . More specifically, insole portion  25 A may be mechanically and securely coupled to one or both of front upper portion  12 A or front outsole portion  14 A, while rear insole portion  25 B may be mechanically and securely coupled to one or both of rear upper portion  12 B or rear outsole portion  14 B. Alternatively, one or both of front insole portion  25 A and a rear insole portion  25 B may be attached to expandable portion  15  by itself or in addition to a portion of upper  12  or outsole  14 , particularly if all or a substantial portion of upper  12  comprises an expandable material, such as those described herein. 
         [0048]    The mechanical couplings of insole portions  25 A and  25 B to other portions of the shoe, which are not explicitly illustrated in the drawings, may be achieved by any known attachment mechanism including, but not limited to, stitching, mechanical fasteners, various natural or synthetic adhesives, or thermal fusing or bonding, etc., depending upon the structural composition of one or both of insole portion  25 A and  25 B. Further the exact location of such mechanical couplings may be left to the discretion of the designer so long as upon lengthwise expansion or contraction of the shoe along its lengthwise axis, the overlapping end regions of each of insole portions  25 A and  25 B are free to move relative to one another. 
         [0049]      FIGS. 9A-9B  are exploded, cross-sectional views of insole  25  in the fully contracted state, i.e., un-extended, state ( FIG. 9A ) and the extended state ( FIG. 9B ), relative to outsole  14  and expandable uppers  12 . As illustrated in  FIGS. 9A and 9B , front insole portion  25 A is disposed adjacent to and below the fore of rear insole portion  25 B so that insole portions  25 A and  25 B are movable relative to each other upon expansion and/or contraction of expandable portion  15 . As portion  15  expands from its normally contracted state to an extended state, insole portion  25 B slides over the top of insole portion  25 A in a rearward direction towards the rear of the shoe  100 B, while insole portion  25 A slides under insole portion  25 B in a forward direction towards the toe of the shoe  100 B, As expandable portion  15  contracts from expanded state, the above-described process reverses itself with insole portions  25 A-B moving opposite to that described above. 
         [0050]      FIGS. 10 and 11  illustrate a high-heeled shoe  100 C which implements the sliding insole concepts disclosed herein. As illustrated in  FIGS. 10 and 11 , front insole portion  25 A is disposed adjacent to and below the fore of rear insole portion  25 B so that insole portions  25 A and  25 B are movable relative to each other upon expansion and/or contraction of expandable portion  15 .  FIG. 11  is a partial view of shoe  100 C in which the insole  25  and outsole  14  are illustrated in solid lines, with the profile the shoe upper  12  illustrated in phantom. As portion  15  expands from its normally contracted state to an extended state insole portion  25 B slides over the top of insole portion  25 A in a rearward direction towards the rear of the shoe  100 C, while insole portion  25 A slides under insole portion  25 B in a forward direction towards the toe of the shoe  100 C. alternatively, insult portion  25  a may be secured to either outsole  14  for over  12  so that it remains fixed relative to insole portion  25 B during both expansion and contraction. 
         [0051]    Note, in shoe  100 C, expandable portion  15  is attached to and interconnects front upper portion  12 A and rear upper portion  12 B or front outsole portion  14 A and rear outsole portion  14 B or both or in combinations thereof, surrounding the overlapping regions of insole portions  25 A and  25 B, thereby defining a zone of expansion and contraction along the lengthwise axis of shoe  100 C. 
         [0052]    As illustrated in  FIGS. 9A-B , the sliding outsole configurations  10 , may be utilized utilized with a sliding insole configuration of shoe  100 B. Similarly, the sliding floating insole configuration of shoes  100 B may be utilized with a multipart outsole  14 A and  14 B in conjunction with a traditional heel  16 , described with reference to  FIGS. 10 through 12B . Note that it is contemplated that the location of the expandable portion  15  in upper  12  may be determined at the discretion of the designer, allowing the point of expansion and contraction to be located proximate the front, middle, rear, or anywhere along the lengthwise will lengthwise axis, of the shoe. 
         [0053]      FIGS. 12A-B  illustrate a shoe  100 D having a floating insole  25  and multipart outsole  14  and multipart upper  12  having an expandable portion  15  located proximate the rear of the shoe proximate heel  16 , as illustrated. Specifically,  FIGS. 12A-12B  are exploded, cross-sectional views of insole  25  in the contracted state, i.e,, un-extended, state ( FIG. 12A ) and the extended state ( FIG. 12B ), relative to outsole  14  and expandable uppers  12 . Front insole portion  25 A is disposed adjacent to and below the fore of rear insole portion  25 B so that insole portions  25 A and  25 B are movable relative to each other upon expansion and/or contraction of expandable portion  15 . As portion  15  expands from its normally contracted state to an extended state, insole portion  25 B slides over the top of insole portion  25 A in a rearward direction towards the rear of the shoe  100 D, while insole portion  25 A slides under insole portion  25 B in a forward direction towards the toe of the shoe  100 D. The construction of the various components of shoe  100  maybe similar to that described with reference to shoes  100 A- 100 C, as applicable. As expandable portion  15  contracts from expanded state, the above-described process reverses itself with insole portions  25 A B moving opposite to that described above. 
         [0054]    Further, it will be obvious to those reasonably skilled in the relevant arts, in light of the teachings and disclosures set forth herein, that the disclosed concepts may be applied to shoes or footwear having shape or style, or targeted to any gender, age group or specific purpose. For example, one or both of the sliding outsole and sliding insole concepts may be equally applicable to any of, including, but not limited to, high-fashion women&#39;s shoes, men&#39;s golf shoes, or children&#39;s recreational shoes, or any other shoe or footwear in which it is desirable to allow for expansion or contraction along the lengthwise axis of the shoe.