Abstract:
Shoe constructions which automatically adjust the effective girth of a shoe to enable the shoe to change in girth throughout a day in accordance with changes in a wearer&#39;s foot, including along the upper and lower side edges of the ball, waist, and instep of the wearer.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention comprises a shoe construction providing improved means for the automatic adjustment of the effective girthwise dimensions of a shoe to properly fit a foot therein, including along the upper and lower sides of the midportional ball, waist and instep of a wearer&#39;s foot throughout the day. 
         [0002]    It is well-known that to fit properly, a shoe need to not only be of suitable length but also of the particular effective girthwise dimension essential to providing a comfortably close girthwise fit to the foot of the wearer. To date, the best approaches to achieving such proper fit have been by having one&#39;s shoes made to order by custom shoemakers, or usually somewhat less expensively by factory-made shoes, particularly those available in a relatively wide range of successive widths, (i.e. girths) for each length size. 
         [0003]    Neither of these approaches has provided full and accurate girth adjustment throughout the shoe and particularly in the fit-critical lower midportional sides thereof for the normal temporary diurnal increases in foot girth due to increases in body fluids in the extremities typically amounting to one or more girth increments over the course of each day. Girth increments range from about 3/16″ to ¼″ depending on the size range of the shoe and the preference of the shoe manufacturer. 
         [0004]    In the latter 20th century, girthwise fitting problems increased appreciably with the now general practice of offering most so-called volume popularly priced footwear in only a single relatively medium width (i.e. girth) for each length size, mainly to minimize retail store inventories for the seemingly ever-increasing range of shoe styles being offered by the suppliers. While negatively affecting the fit of most styles including those of the popular laced shoe constructions, these factors have had particularly adverse effects on conventional casual shoes such as loafers and similar slip-on categories lacking conventional manual girth adjustment means. The typical medium width (girth) limitation of such shoes results in their providing proper fit to few if any wearers throughout a typical day. 
         [0005]    The present invention overcomes these problems, providing shoes that will fit each foot properly throughout the day. Moreover, the present construction keeps the foot transversely centered in the shoe at all girth adjustments, a factor that should be most welcome in athletic and other active wearing use applications. 
         [0006]    Additionally, while the disclosure below refers to a handsewn loafer shoe design, this invention is readily applicable to other shoe designs and categories including those with manually adjustable shoe laces, straps, buckles and similar means affording additional girth or girthwise tensional adjustment in combination with the girth adjustment system of this invention. 
         [0007]    As for relevant prior art, none has been able to satisfy the foregoing criteria sufficiently to merit its volume production to date. Such prior art includes the following U.S. Pat. Nos. 2,691,271; 3,404,468; 3,442,031; 3,541,078; 3,618,235; 3,686,777; 4,279,083; 4,858,341; 4,967,492; 4,969,277; 5,060,402; 5,123,181; 5,153,257; 5,203,096, 5,241,762; 5,325,514; 5,384,970; 6,725,575 and 6,883,254. 
       SUMMARY OF THE INVENTION 
       [0008]    This invention comprises shoe constructions which provide improved means for automatically adjusting the effective girth of a shoe by an elastic means which extends longitudinally along at least a portion of the shoe so that the shoe provides a comfortably contacting fit of the shoe to a wearer&#39;s foot therein while keeping the foot substantially transversely centered in the shoe at all girth adjustments thereof. The shoe constructions include a foot support surface having a width equal to or less than the narrowest foot for which the shoe is intended. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a side elevational cross-sectional drawing of a first shoe  20  taken along its longitudinal centerline and embodying principles of the present invention. 
           [0010]      FIGS. 2 and 3  show plan views of elements of the shoe  20  of  FIG. 1  taken along the lines  2 - 2  and  3 - 3  thereof with  FIG. 2  showing these elements as they would appear with the shoe  20  girth adjusted to fit a foot of lesser girth while  FIG. 3  shows these elements adjusted to fit a foot of greater girth. 
           [0011]      FIG. 4  is a side elevational cross-sectional drawing of a second shoe  120  taken along its longitudinal centerline and embodying principles of the present invention. 
           [0012]      FIGS. 5 and 6  show plan views of the shoe  120  of  FIG. 4  taken along the lines  5 - 5  and  6 - 6  thereof, with  FIG. 5  showing these elements as they would appear with the shoe  120  adjusted to fit a foot of lesser girth, while  FIG. 6  shows the same elements when adjusted to fit a foot of greater girth. 
           [0013]      FIG. 7  is side elevational cross-sectional drawing of a third shoe  220  taken along its longitudinal centerline and embodying principles of the present invention. 
           [0014]      FIGS. 8 and 9  show plan views of the shoe  220  of  FIG. 7  taken along the lines  8 - 8  and  9 - 9  thereof, with  FIG. 8  showing these elements as they would appear with one version of the shoe  220  adjusted to a lesser girth while  FIG. 9  shows these same elements adjusted for the same version of the shoe  220  to a greater girth. 
       
    
    
     DEFINITIONS 
       [0015]    The following definitions will be used in reference to terms and phrases in this disclosure: 
         [0016]    “Ball to instep girth ratio”—The ratio of the girth of a foot at its ball relative to that at its instep. 
         [0017]    “Bottom element”—Shoe element predominantly under a foot therein. 
         [0018]    “Centerline”—The longitudinally central line of a shoe and bottom elements thereof. 
         [0019]    “Direct sole molding”—Shoe manufacturing process in which the sole element of a shoe is both molded and attached to a shoe upper assembly in the same molding operations. 
         [0020]    “Effective girth”—The transverse circumferential dimensions of the innermost elements of a shoe. 
         [0021]    “Elastic fabric”—A fabric having an elasticity of about 1 to 10, preferably about 2 to 6, pounds per inch of width, i.e. about the girthwise elasticity of a typical waistband of mens so-called “Jockey” underwear. 
         [0022]    “Elastic goring”—Elastic fabric tape, preferably elasticized by neoprene rubber based components. 
         [0023]    “Fit-critical”—Critical to the fit thereof. 
         [0024]    “Fixed insole”—Insole bottom element of a shoe fixedly attached to adjacent elements thereof. 
         [0025]    “Forepart spacer”—Optional shoe bottom element in the forepart of a shoe, preferably of fiberboard or equivalent material of a thickness matching that of the tuck element and midportional transverse goring of a shoe. 
         [0026]    “Interlining”—Lining element located between the upper and lining elements of a shoe. 
         [0027]    “Lining”—Inner element of a shoe, located adjacent to a foot therein. 
         [0028]    “Loose”—Less than continuous attachment of a shoe element to adjacent elements thereof. 
         [0029]    “Lower side portions”—Side portions approximately 1 to 3 cm, above the uppermost foot supporting element of the shoe. 
         [0030]    “Midportional”—Longitudinally relatively central location of a foot or shoe, including ball, waist and instep portions thereof. 
         [0031]    “Polypropylene”—Typically extruded polypropylene polymer. 
         [0032]    “Proper fit”—The accepted comfortably close fit of a shoe to a foot therein. 
         [0033]    “Rubberized”—A process by which latex based elements of a shoe become rubber by the application of vulcanizing heat thereto. 
         [0034]    “Shank”—Portion of a foot or a shoe between the instep and heel portions thereof. 
         [0035]    “Shoe”—General term for footwear of various categories. 
         [0036]    “Spandex fabric”—Fabric including elastic spandex fibers. 
         [0037]    “Tensionally adjustable”—Adjustable by the application of tension thereto. 
         [0038]    “Tuck”—Bottom element of a shoe, typically of fiberboard material, extending between the ball (or waist) and heel thereof. 
         [0039]    “Unitsole”—Unitary bottom-most element of a shoe. 
         [0040]    “Upper side portions”—Side portions of a foot or shoe located above the lower side portions. 
         [0041]    “Vulcanized shoe”—A shoe construction wherein latex based elements and adhesives of a shoe are secured to each other and rubberized by the application of (vulcanizing) heat thereto. 
       DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0042]      FIGS. 1-3  show a first embodiment of the principles of the present invention. Shown is a popular so-called hand-sewn loafer design casual shoe  20 . 
         [0043]      FIG. 1  shows the loafer styled shoe  20  which includes an upper assembly  22  having a vamp  24  attached to a plug  26  by a handsewn seam  28 , and a counter  30 , a cuff  32  and a saddle  34  attached to the vamp  24  by conventional trim-stitching  36  and by a handsewn seam  28 , and to the topline of the vamp  22  by such as conventional topline stitching (not shown).  FIG. 1  further shows two midportional flexibly inelastic girth adjustable fabric interlining panels  40  (one on each side of the shoe). The panels  40  are attached to the topline of the vamp  24  by topline stitching (not shown) and by the hand-sewn seam  28 . The panels are located between the shoe outer vamp elements and a loose spandex vamp lining  48 . 
         [0044]      FIG. 1  also shows lining and bottom elements of the shoe  20  of  FIG. 1  including the loose spandex vamp lining  48  which extends as shown across a portion of the top surface of a fiberboard tuck  50  and the forepart of a flexibly inelastic fixed insole  52 . The vamp lining  48  is attached to the peripheries of both the fiberboard tuck  50  and the fixed insole  52  by such as adhesive cement means. This allows the lining to be slightly elastic along the sides of the shoe but substantially inelastic under the foot. The fiberboard tuck  50  contains a midportional centerline eyelet  54  which is positioned forward of a preferably neoprene rubber based elastic fabric centerline goring  56  and over the fixed insole  52  which has a conventional shoe bottom assembly  58  thereunder. Preferred shoe bottom assemblies include vulcanized direct molded unitsoles as well as other soles and bottom assemblies. 
         [0045]      FIGS. 2 and 3  show plan views of the bottom elements and adjacent girth adjustment means of the shoe  20  of  FIG. 1  when viewed upward from the fixed insole  56 .  FIG. 2  shows these elements as they would be when the shoe is adjusted to fit a lesser girth foot.  FIG. 3  shows the same elements as in  FIG. 2  as they would be when the shoe is adjusted to fit a foot of greater girth. Both figures show the elastic fabric goring  56  being attached to the heel portion of the tuck  50  by a heel edge-stitching means  62 . 
         [0046]    In use, a preferably braided Dacron® sportfishing or similar line  66  is attached to a first panel  40 , then the line extends through centerline eyelet  54 , then passing through a goring eyelet  64  in the elastic fabric goring  56 , then back through centerline eyelet  54 , and then attached to the second panel  40 . Each of the panels  40  preferably has a longitudinal, polypropylene (or other plastic) strut  70  attached as by butt-stitching  72  to the inelastically flexible fabric panels  40 . The polypropylene struts  70  both reinforce the fabric panel at the point of connection to the line  66  as well as automatically angularly align to adjust for differences in the ball to waist girth ratio of a wearer&#39;s foot from those of the norm while keeping the foot transversely centered in the shoe  20  at all girth adjustments. The polypropylene strut is generally about 0.2″ to 0.3″ thick, preferably about 0.023″ to 0.028″ thick. 
         [0047]    At the least girth adjustment of the shoe  20  the goring  56  exerts at least about 1 pound of tension when no foot is in the shoe (or a foot of minimum girth). This minimum amount of tension helps the shoe have a comfortable fit on the foot and avoid heel-slip in the stride. The specific degree and range of the initial tension will depend on the expected end use of the shoe  20  and any preference of its supplier. 
         [0048]    The tension is exerted on the goring by means of a preferably braided Dacron® sportfishing or similar line  66  which extends forward from an eyelet means  64  in the goring to and through the centerline eyelet  52  in the tuck  50  and transversely therefrom to a knotted line end attachment  68  in the waist portion of each of the two inelastically flexible fabric interlining panels  40 . 
         [0049]      FIGS. 4-6  show a second embodiment of a shoe of the present invention. These drawings show a popular so-called hand-sewn saddle loafer design of casual shoe  120  in an elevational cross-section taken along its longitudinal centerline. 
         [0050]      FIG. 4  shows a shoe  120  including an upper assembly  122  having a vamp  124  attached to a plug  126  by a handsewn seam  128  and a cuff  130 , a saddle  132 , and an inside counter (not shown) attached to the vamp  124  by a conventional trim-stitching  134  and by a conventional vamp topline stitching (not shown).  FIG. 4  further shows a midportional transverse elastic fabric element  136  and optional preferably extruded polypropylene plastic girth adjustment limiting struts  138 , both attached to the vamp  124  by said vamp topline stitching (not shown). The midportional transverse elastic fabric element  136  is about 1 to 2.5 inches wide. The midportional transverse elastic fabric element  136  is shown as a single element from one shoe top line to the other, but it can be in two or more strips each about 0.5 to 1.25 inches wide wherein the strips may or may not be physically connected to each other. The adjustment limiting struts  138  serve to prevent the top line of a side of the shoe from going below the designed minimum which is required for the shoe to fit the minimum girth foot for which it has been designed. The limiting struts  138  may be about ½ inch wide. 
         [0051]      FIG. 4  also shows a spandex loose fabric lining  140  attached to the topline of the vamp  124  by the topline stitching (not shown) and in the forepart of the shoe by the handsewn seam  128 . The loose fabric lining  140  serves to provide a smooth inside foot contacting surface at all girths. If desired, the loose fabric lining  140  may be cemented to a preferably ⅛″ Poron® cellular polyurethane foam socklining  142  which may be similarly cemented to a preferably 0.025″ polypropylene insole  144  thereunder. The insole  144  may be similarly cemented to a tuck element (rearpart spacer)  146  and optionally a forepart spacer  148 , both being preferably of fiberboard of similar thickness to the thickness of the elastic fabric  136  therebetween to allow automatic girth adjustment of the shoe  120  by the elastic fabric  136  over the designed girth adjustment range of the shoe  120 . The tuck element  146  and the optional forepart spacer  48  may be cemented to a fixed insole  150  thereunder. The fixed insole  150  is typically a flexibly inelastic fabric attached as by butt-stitching (not shown) to the lower periphery of the vamp  124  and then cemented or otherwise attached to the sole element or bottom assembly  152  thereunder. 
         [0052]      FIGS. 5 and 6  show plan views of bottom elements and girth adjusting means of the shoe  120  of  FIG. 4  as viewed upwards from its fixed insole  150 .  FIG. 5  shows these elements as they would appear with the shoe  120  adjusted to a lesser girth while  FIG. 6  shows the adjustment to a greater girth. Both figures show the tuck  146  and forepart spacer  148  and the gore  136  therebetween. 
         [0053]    Referring to  FIGS. 7-9 , they show a third version of a popular so-called hand-sewn saddle loafer casual shoe style in an elevational cross-section taken along its longitudinal centerline in a construction embodying principles of the present invention. 
         [0054]      FIG. 7  shows a shoe  220  including an upper assembly  222  having a vamp  224  attached to a plug  226  by a handsewn seam  228 , and a saddle  230  and a cuff  232 , both attached to the vamp  224  and the plug  226  by trim-stitching  234  and by vamp topline stitching (not shown).  FIG. 7  further shows a spandex loose lining  236  having its lower portion cemented to the top surface of a loose insole  238 . The loose insole  238  preferably is of a width equal to that of a shoe last of the least girth of the girth adjustable range for which the shoe  220  is designed.  FIG. 7  also shows two preferably flexibly inelastic about 0.025″ thick woven fabric panels  240  attached to the vamp  224  topline by stitching (not shown). The lower portions of the fabric panels  240  extend transversely under the loose insole  238  and above a flexible, substantially inelastic, woven fabric fixed insole  242 . The flexible woven fabric fixed insole  242  is attached, as by butt-stitching, to the lower periphery of the vamp  224  over a vulcanized type bottom assembly or unitsole  244 .  FIG. 7  further shows a centerline eyelet  46  in the waist of loose insole  238  and an eyelet  248  in the centerline instep slot  250 , eyeletted to a transverse polypropylene strut  252  (preferably about 0.025″ thick) which is butt-stitched to a suitably tensioned elastic centerline fabric tape  254  (as better seen in  FIGS. 8 and 9 ) between the eyelets  246  and  248 . 
         [0055]      FIGS. 8 and 9  show plan views of the elements of the shoe  220  of  FIG. 7  as viewed upwards of its fixed insole  242 .  FIG. 8  shows these elements as they would appear with the shoe  220  adjusted to a lesser girth while  FIG. 9  shows their adjustment to a greater girth.  FIGS. 8 and 9  also show the preferably 0.025″ thick polypropylene longitudinal ball to instep struts  256  attached as by butt-stitching to the lower end portions of the fabric panels  240 . The struts  256  are attached at their waists to a preferably braided Dacron® girth adjusting line  258  which extends transversely from the struts to the centerline slot  250  in loose insole  238  and attached thereby to the center of a preferably 0.025″ thick polypropylene transverse strut  52  butt-stitched to the centerline elastic fabric tape  54  which is attached as by heel-stitching  50  to the heel perimeter of insole  238 , preferably under a minimum longitudinal tape tension of about 3 lbs. This arrangement allows a wearer&#39;s foot to be held relatively centered transversely within the shoe while allowing the fit-critical ball to instep girth ratio of the shoe to automatically adjust to that of the wearer at all girth adjustments thereof. 
         [0056]    It should also be noted that the constructions of this invention are applicable to shoe designs that in addition to the automatically girth-adjusting structures described herein further include a conventional manually girth adjustable means such as laces, straps, and the like. The manual means can be useful in providing additional incremental girth-wise or tensional adjustment along with the automatic girth adjustment elements of the present invention. 
         [0057]    Equivalents to the elements specified above for use in the present invention include a full length insole in place of or in addition to the tuck element; other elastic means such as springs or metal extension springs and the like in place of the centerline elastic fabric goring  56 ; multiple non-centerline elastic fabric gorings in place of a centerline elastic fabric goring  56 ; having the elastic fabric goring extend from the toe toward the shoe instep; and the like. 
         [0058]    As for materials and sources, leather may be from Prime Tanning, Inc., of Berwick, Me. Synthetic leather and similar sheet materials may be from Starensier, Inc., of Newburyport, Mass. Spandex, elastic fabric, flexibly inelastic fabrics, and goring may be from the Geo. C. Moore Co. Inc., of Westerly, R.I. Polypropylene extrusions may be from Bixby International, Inc., of Newburyport, Mass., or Spartech Plastic, Portage, Wis. Eyelets and washers may be supplied by Trendware/Goldberg Footwear Components, Inc., of Salem, Mass. Polyurethane cellular sheet materials such as Poron® may be from Rogers Corp., Rogers, Conn. Dacron fishing line may be from Woodstock Line Co., Putnam, Conn.