Patent Publication Number: US-2012025480-A1

Title: Size-adjustable footwear

Description:
TECHNICAL FIELD 
     The present invention relates to size-adjustable footwear, and in particular to footwear able to accommodate growth of children&#39;s feet. 
     BACKGROUND OF THE INVENTION 
     To address the problem of new children&#39;s shoes becoming too small as the feet grow it is common for new shoes one or two sizes too large to be purchased. For ordinary walking shoes the poor fit and possible resulting discomfort may be insignificant during the time the shoes are over-size, however footwear for sporting use must be as perfectly fitted as possible. It is important that the foot is supported securely and comfortably to allow good control over movements during the sporting activity. It will be apparent that there is a need for sporting footwear able to be more perfectly fitted and that reduces the demand for regular and costly replacement as children grow. 
     Interchangeable insoles are used to take up some of the excess volume in moderately over-size sporting footwear. These insoles underlie the sole of the foot, raising the foot relative to the footwear. They may be formed from a resilient sheet of uniform thickness, or have a variable thickness (for instance, increasing at the arch) to fill the excess space between the sole of the foot and the inside of the shoe. In some applications, such as skates having a boot to which the wheels are fixed in a non-adjustable manner, the proper fore-and-aft positioning of the foot relative to the centre of the skate is important for skating performance and balance. However with these prior art interchangeable insoles no provision is made for proper positioning in this respect. It is an object of the present invention to overcome or substantially ameliorate the above disadvantages or more generally to provide an improved sports footwear for children. 
     DISCLOSURE OF THE INVENTION 
     According to one aspect of the present invention there is provided size-adjustable footwear comprising: 
     a body having a body heel, a body sole and a body upper; 
     first and second insoles removably received within the body, each insole comprising integral sections including a forefoot-supporting section and a midfoot- and heel-supporting section, 
     the forefoot-supporting section of the first insole having a reentrant form for partially enclosing at least part of the periphery of the forefoot and including a first toe cap at a tip thereof, and lateral and medial flanges integral with the first toe cap, the first toe cap and lateral and medial flanges terminating in an arcuate forward edge; 
     the midfoot-supporting section of the first insole having a non-reentrant form including opposing first medial and first lateral edges and a first arch-supporting portion with a concave convex inner side for facing the arch of the wearer&#39;s foot, the heel-supporting section of the first insole including a reentrantly shaped heel cup to partially enclose the heel, 
     the forefoot-supporting section of the second insole having a reentrant form with an integral second toe cap at a tip thereof, 
     the midfoot-supporting section of the second insole having a non-reentrant form including opposing second medial and second lateral edges and a second arch-supporting portion with a concave convex inner side for facing the arch of the wearer&#39;s foot, 
     the heel-supporting section of the second insole having a non-reentrant form with an arcuate peripheral edge, wherein first and second insoles generally overlie one another, and one of the first and second insoles generally overlies the body sole, the first and second toe caps are complementary to one another, one of the first and second toe caps being received within the other of first and second toe caps. 
     Preferably the first insole generally overlies the second insole and the second insole generally overlies the body insole and a first longitudinal dimension between the heel cup and the second toe cap defines a first size and a second longitudinal dimension between the heel cup and the first toe cap defines a second size greater than the first size. 
     Preferably the second medial edge is offset downwardly of the first medial edge. 
     Preferably the first and second insoles are formed from a resilient self-supporting material. 
     Preferably the body comprises a rigid polymer shell. 
     Preferably the footwear comprises sports footwear such as skates, ski boots and gym shoes. Most preferably the footwear further includes inline wheels mounted to the body sole. 
     In use, the footwear is chosen to fit a child&#39;s feet of the first size, such that as the feet grow the first insole may be removed to accommodate feet of the second size, then following further growth the second insole is removed to accommodate feet of a third size. In this manner the invention provides footwear which reduces footwear replacement costs without compromising fit and performance. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: 
         FIG. 1  is a longitudinal section through an exemplary embodiment of footwear according to the invention; 
         FIG. 2  is a plan view of a first insole of the footwear of  FIG. 1 ; 
         FIG. 3  is a section along line AA of  FIG. 2 ; 
         FIG. 4  is a section along line BB of  FIG. 2 ; 
         FIG. 5  is a section along line CC of  FIG. 2 ; 
         FIG. 6  is a plan view of a second insole of the footwear of  FIG. 1 ; 
         FIG. 7  is a section along line FF of  FIG. 6 ; 
         FIG. 8  is a section along line DD of  FIG. 6 ; 
         FIG. 9  is a section along line EE of  FIG. 6 , and 
         FIG. 10  is a transverse section through the first and second insoles at the arch-supporting region. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIG. 1 , a size adjustable inline skate  10  includes a body  11  having a body sole  13  and a body upper  14  and body heel  20  and body toe  21 . A pair of inline wheels  15  is mounted to the bottom of the body sole. The body  11  is constructed from a rigid polymer shell  16  having a resilient liner  17  for fitting the wearer&#39;s foot (not shown). A first insole  18  generally overlies a second insole  19 , the second insole  19  in turn generally overlies the body sole  13 , with both insoles  18 ,  19  extending from the body heel  20  to the body toe  21 . 
     Both the insoles  18 ,  19  are generally thin, one-piece items, moulded from a resilient, self-supporting material such as polyethylene foam. 
     Referring to  FIGS. 2-5 , the first insole  18  includes integral sections including a forefoot-supporting section  40 , a midfoot-supporting section  41  and a heel-supporting section  42 . In  FIGS. 2-5  three contour lines drawn in dashed lines are provided to better show the shape of insole  18 , and represent three parallel planes evenly spaced above a base  26  of the insole  18 . 
     An integrally-moulded toe cap  43  extends about the end and sides of the tip of the forefoot-supporting section  40  and is continuous with the base  44  of the insole  19 . The toe cap  43  has a reentrant form, extending upward and backward away from the outermost edge  45 . Lateral and medial flanges  67  and  68  are integral with the toe cap  43  and the base  44 . Forward of the widest part of the second insole  19  (which lies along line DD of  FIG. 6 ) the lateral and medial flanges  67 ,  68  have a re-entrant form with concave inner surfaces covering opposing sides of the forefoot. The toe cap  43  is complementary to and nested within the toe of the body upper  14 , as seen in  FIG. 1 . The toe cap  43  and lateral and medial flanges  67 ,  68  terminate in an arcuate forward edge  46  offset inwardly of the outermost edge  45  of the forefoot-supporting section  40 . 
     The midfoot-supporting section  41  includes an arch-supporting portion  49  shaped complementary to the arch of the wearer&#39;s foot, having an inner side  48  of convex curvature. The sides of midfoot-supporting section  41  are turned upwardly, but are non-reentrant, and terminate in medial and lateral edges  50  and  51  respectively which curve smoothly to blend with the ends of the forward edge  46 . The insole  19  generally engages with the entire inner surface of the insole  18  upon which it is supported, except for the portion  60  (shown in  FIGS. 1 and 10 ) of midfoot-supporting section  41  which extends above the edge  33 . 
     The heel-supporting section  42  is also non-reentrant and includes with an arcuate peripheral edge  35  which smoothly blends with the medial and lateral edges  50  and  51 . 
     As shown in  FIGS. 6-9 , the second insole  19  includes integral sections including a forefoot-supporting section  22 , a midfoot-supporting section  23  and a heel-supporting section  24 . The three dashed contour lines in  FIGS. 6-9  correspond to those in  FIGS. 2-5 . The outer surface of the second insole  19  is complementary to the inner surface of the liner  17 . 
     The forefoot-supporting section  22  is characterized by having an integrally-moulded toe cap  25  which is continuous with the base  26  of the insole  18  and which has a reentrant form, extending upward and backward. Lateral and medial flanges  27  and  28  are integral with the toe cap  25  and the base  26 . The lateral and medial flanges  27 ,  28  also have a re-entrant form with concave inner surfaces covering opposing sides of the forefoot. The front of the forefoot-supporting section  22  (forward of the widest part of the second insole  19  which lies along line BB of  FIG. 2 ) therefore has a reentrant form. The toe cap  25  and lateral and medial flanges  27 ,  28  terminate in an arcuate forward edge  29  offset inwardly of the outermost edge  30  of the forefoot-supporting section  22 . 
     The midfoot-supporting section  23  includes an arch-supporting portion  31  shaped complementary to the arch of the wearer&#39;s foot, having an inner side  32  of convex curvature (as shown by the dashed contour lines and in  FIG. 5 ). The sides of the midfoot-supporting section  23  are turned upwardly, but are non-reentrant, and terminate in medial and lateral edges  33  and  34  respectively which curve smoothly to blend with the ends of the forward edge  29 . The medial edge  33  rises to a high point above the base  26  generally in the centre of the arch-supporting portion  31 , smoothly curving downwardly from this high point toward the front and rear. The lateral edge  34  extends at approximately a constant height above the base  26  along the length of the midfoot-supporting section  23 . 
     The heel-supporting section  24  has a lower part for underlying the heel and a reentrantly shaped heel cup  55  with a relatively short longitudinal extent to partially enclose the heel. The heel cup  55  terminates in an upper edge  57  that lies in a plane parallel to the base  26 . The upper edge  57  is joined by arcuate, concave edges  56  which smoothly blend with the medial and lateral edges  33  and  34 . 
     As shown in  FIG. 10 , when both the insoles  18 ,  19  are received in the skate  10 , the second medial edge  50  is offset upwardly of the first medial edge  33 . Offsetting the edges  50 ,  33  in this manner provides in the instep area a more gradual volume change or tapering at the edges when both insoles are in place. Similarly, on the opposing outer side the second lateral edge  51  is offset vertically with the first lateral edge  34 . 
     When new the skates  10  are sized to fit the user with both insoles  18 ,  19  nested together within the body, as shown. This provides a first size defined by a first longitudinal dimension between the heel cup  55  and the first toe cap  43 . The insole  19  may subsequently be removed to define a second size greater than the first size, defined by an internal longitudinal dimension between the heel cup  55  and the toe cap  25 . In an exemplary embodiment, the longitudinal difference between the first and second sizes is 6.6 mm, taken up the toe cap  43 . The longitudinal difference between the second and the third size is 6.6 mm, of which 3.3 mm is taken up by each of the heel cup  55  and the toe cap  25 . From the toe caps  25  and  43  the thickness tapers to 1.5 mm for both the lateral and medial flanges  27 ,  28 ,  67 ,  68  so that for both the first and second sizes a total lateral reduction of 6 mm is provided relative to the third size. The base  26 ,  44  of both insoles  18 ,  19  is approximately 1.5 mm thick. It has been found that this arrangement provides optimal or near optimal fitting as well as longitudinal, transverse and vertical positioning of the user&#39;s feet in the three different sizes. In particular, the heel cup move the foot forward, ensuring better fore-and-aft positioning of the foot relative to the centre of the skate. This size adjustment also achieved with a minimum of material, providing footwear with a lightweight, relatively low cost size adjustment. 
     Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.