Patent Publication Number: US-2015068059-A1

Title: Open Styled Footwear and Components Therefor

Description:
FIELD 
     The present disclosure relates generally to an article of open styled footwear and to anatomically contoured support elements capable of incorporation into such footwear. The disclosure has been described with reference to open styled footwear in the form of flip-flops, but it is to be appreciated that the disclosure is not limited to that use, and may be applied to a broad range of footwear. 
     BACKGROUND 
     Open styled footwear, in particular open styled footwear consisting of a flat sole held loosely on the foot by a Y-shaped strap that passes between the first and second toes and around either side of the foot (commonly known as flip-flops or thongs) are popular despite the fact that such footwear offers little foot support. Open styled footwear has been linked with foot discomfort, postural imbalances and musculoskeletal injury including plantar fasciitis (arch pain) compartment syndrome (shin pain), metatarsalgia (ball of foot pain) and ankle sprains and fractures as well as foot strains and fractures. Media reports and hospital figures over the past five years estimate casual footwear such as flip-flops result in more than 200,000 people attending medical centres each year after suffering falls or developing long-term problems. The National Health Service of the United Kingdom spends £40 million a year treating injuries caused by wearing such open styled footwear. Podiatry organizations, foot surgeons and hospital departments are regularly interviewed in the media to inform and educate about the hazards of wearing flip-flops. 
     Some embodiments of open styled footwear and various anatomically contoured support elements described herein seek to address at least some of the aforementioned problems. 
     The above references to the background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the open styled footwear and various anatomically contoured support elements as disclosed herein. 
     SUMMARY OF THE DISCLOSURE 
     In a first aspect there is disclosed an article of open styled footwear comprising a sole member, a strap fixed relative to the sole member, and an interdigit toe piece disposed between an upper portion of the strap and the sole member, whereby the article of footwear is retained to a foot, at least in part, by the upper portion of the strap extending over the foot and the interdigit toe piece being disposed between the first and second toes, the interdigit toe piece comprising a body having opposing concave side surfaces configured, in use, to separate and cradle the first and second toes. 
     In one embodiment, the toe piece body includes an aperture in an upper surface that receives a lower portion of the strap. 
     In one embodiment, the aperture extends through the toe piece body and the lower portion of the strap is secured to the sole member underlying the toe piece. In a particular form, the aperture in the toe piece body is aligned with an aperture in the sole member and the lower portion of the strap extends through the toe piece and the sole member and is retained to an underside of the sole member. 
     In one embodiment the opposing concave side surfaces are anatomically contoured with respect to the first and second toes. In one embodiment, a rear surface of the body is configured, in use, to receive an interdigit web disposed between the first and second toes. 
     In one form, a lower surface of the toe piece is fixed to, or integrally formed with, the sole member. Advantageously, integration of the toe piece with the sole member may thicken and thereby strengthen a region of the sole member which in previous open style footwear has been prone to wear and failure particularly in arrangements where a lower portion of strap is fixed to the sole member. 
     In an alternative form, the toe piece may be fixed to, or integrally formed with, the strap. In this arrangement, the toe piece is disposed between the upper and lower portions of the strap. In such an arrangement the lower portion is fixed to, or integrally formed with, the sole member. In a particular form the lower portion of the strap extends through an aperture in the sole member. 
     In one form, the toe piece is integrally formed with an inlay which in turn forms part of the sole member. 
     In a particular form, the inlay provides support for the foot. In one embodiment the inlay includes forward and rear bulbous portions that are generally shaped to conform with respective pressure regions of the ball and heel of the foot. In this respect, the footbed inlay may be formed from a cushioning material to provide additional comfort in those regions. 
     In a second aspect of the disclosure, there is provided a footbed inlay for an article of open styled footwear comprising a sole member, a strap fixed relative to the sole member, whereby the footwear is retained to a foot, at least in part, by an upper portion of the strap extending over the foot, the foot bed inlay comprising a body having a forward bulbous portion interconnected with a rear bulbous portion by an isthmus-shaped section, and a interdigit toe piece upwardly extending from the forward bulbous portion, wherein in use the inlay body forms part of the sole member and the interdigit toe piece is disposed between the upper portion of the strap and the sole member and is arranged to be disposed between the first and second toes. 
     In one embodiment the footbed inlay is configured to be received in a complementary shaped recess in the sole member. 
     In one embodiment, the interdigit toe piece is integrally formed with the inlay body. 
     In a further aspect, the disclosure provides an article of open styled footwear incorporating the footbed inlay according to any form described with respect to the second aspect. 
     In a further form, the article of open style footwear according to any form described above, further comprises a cushion having a midsole portion and a heel portion disposed with and extending between respective midsole and heel regions of the sole member, wherein the midsole portion comprises an arched cushion portion contoured to support a medial longitudinal arch of the foot and the heel portion contoured to provide medial-varus heel support to the foot. The arched cushion portion may be in the form of an arch cookie. 
     In one embodiment, the heel portion is laterally curved. 
     In one form, the heel portion provides the sole member with an inward lateral camber in a heel region thereof. The inward lateral camber may be between about 4-6 degrees. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Notwithstanding any other forms which may fall within the scope of the open styled footwear and support elements as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying drawings in which: 
         FIG. 1  is a perspective view of an article of open styled footwear in accordance with one specific embodiment; 
         FIG. 2  is a side view of a footbed inlay with an integral interdigit toe piece in accordance with a specific embodiment, showing the relationship between the interdigit toe piece and a strap for use with an article of open styled footwear; 
         FIG. 3  is a perspective view of the footbed inlay and interdigit toe piece shown in  FIG. 2 ; 
         FIG. 4  is an upper plan view of the footbed inlay and interdigit toe piece shown in  FIGS. 2 and 3 ; 
         FIG. 5  is a front end view of another specific embodiment of the interdigit toe piece when worn between a first toe and a second toe; 
         FIG. 6  is a plan view of a pair of cushion elements of one embodiment, capable of incorporation into respective sole members for pair of articles of open styled footwear; 
         FIG. 7  is a plan view of an article of open styled footwear for a left foot, showing a left foot cushion element from  FIG. 6  incorporated into the sole member; 
         FIG. 8  is a perspective view of the cushion element; and 
         FIG. 9  is rear view of a right foot wearing the article of open styled footwear, showing the lateral camber rendered to the sole member by the cushion element when incorporated into the sole member. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     The description broadly relates to article of open styled footwear and components therefor. In particular there is disclosed an article of open styled footwear and anatomically contoured support elements capable of incorporation into such footwear to provide ergonomic support to various parts of the foot. Such anatomically contoured support elements may include an interdigit toe piece, a footbed inlay, and an arch cookie. 
     The term “open styled footwear” as used herein refers to a type of casual footwear having an open toe, open heel and generally flat sole. Examples of such “open styled footwear” are commonly known as thongs but also referred to as flip-flops, thongs, sandals, zories, slip slaps, pluggers, double pluggers, toesies, jandals or slippers. Generally, the sole is held loosely to the foot by a Y-shaped strap that passes between the first and second toes and around either side of the foot. 
     Referring to  FIG. 1  there is shown an article  10  of open styled footwear. The article  10  includes a generally flat sole member  12  and a Y-shaped strap  14 . The Y-shaped strap  14  has a forward strap portion  16  having an upper portion  16   a  and a lower portion  16   b  and a pair of opposing rear strap portions  18 , each having an upper portion  18   a  and a lower portion  18   b . In use, the upper portions  16   a ,  18   a  extends over a wearer&#39;s foot and the lower portions  16   b ,  18   b  engage the sole member  12 . Each free end  20  of the lower portions  16   b ,  18   b  has a stop member  20   a , as shown in  FIG. 2 . 
     The forward strap portion  16  is connected proximal to a front end  22  of the sole member  12  at a first connection point  24  generally coinciding with a region between where a first toe and a second toe reside when the article  10  is worn. The rear strap portions  18  are connected at respective second connection points  26  adjacent opposing sides  28  of the sole member  12  corresponding, in use, to either side of a wearers foot. It will be appreciated that, depending on the design of the article  10 , the rear strap portions  18  may be located at any point along the length of the opposing sides  28  of the sole member  12 , ranging from promixal the ball of the foot to adjacent either side of the heel. 
     The forward strap portion  16  is connected to the front end  22  of the sole member  12 , and the rear strap portions  18  are connected to respective opposing sides  28  of the sole member  12 , as described above by providing the front end  22  and the opposing sides  28  of the sole member  12  with apertures (not shown) generally coinciding, respectively, with the first and second connection points  24 ,  26 . Respective free ends  20  of the forward and rear strap portions  16 ,  18  are passed through the apertures in the sole member  12 . The stop members  20   a  bear against an underside of the sole member  12  when the strap  14  is placed under tension, thereby preventing the free ends  20  of forward and rear strap portions  16 ,  18  from being withdrawn from the apertures and disconnecting from the sole member  12 . 
     The article  10  also includes a footbed inlay  29  that forms part of the sole member  12 . The footbed inlay has a body  30  with an interdigit toe piece  32  integrally formed therein. The footbed inlay body  30  is a generally flat, foot shaped insert that is received in a complementary recess  34  in a base portion  35  of the sole member  12 . 
     Referring to  FIGS. 3 ,  4  and  5  that illustrate the footbed inlay body  30  and the interdigit toe piece  32  in more detail, the footbed inlay body  30  comprises a forward bulbous portion  36  interconnected with a rear bulbous portion  38  with an isthmus-shaped section  40 . The forward and rear bulbous portions  36 ,  38  are generally shaped to conform to respective pressure regions of the ball and heel of the foot. 
     The footbed inlay body  30  is fabricated from a cushioning material to provide comfort to the wearer, in particular to provide cushioning for the weight bearing regions of the ball and heel of the foot. Such cushioning materials are well known to those skilled in the art. Illustrative examples include, but are not limited to, ethyl vinyl acetate (EVA), polyurethane (PU), and open or closed cell rubber. 
     The interdigit toe piece  32  is disposed between an upper portion  16   a  of the strap  14  and the sole member  12 , and is generally disposed in a region between where a first toe and a second toe reside when the article  10  is worn. In the embodiments illustrated in the Figures, the interdigit toe piece  32  is formed as a single moulded piece with the forward bulbous portion  36  of the footbed inlay body  30 . Accordingly, in these embodiments, the interdigit toe piece  32  is fabricated from the same material as the footbed inlay body  30 , such as the cushioning material. 
     Integration of the interdigit toe piece  32  with the footbed inlay body  30  prevents movement of the interdigit toe piece  32  with respect to the sole member  12  when the wearer is walking, thereby allowing the correct position of those components to be maintained. 
     The interdigit toe piece  32  comprises a body  42  having opposing concave side surfaces  44 . The concave side surfaces  44  are configured, in use, to separate and cradle the first and second toes, as shown in  FIG. 5 . Advantageously, separation of the first and second toes enhances the efficiency of first toe joint kinematics by preventing a valgus orientation of the first toe, redistributing weight load from the smaller second toe to the larger first toe, and improving the direction of motion (dorsiflexion) of the first toe, thereby improving overall foot biomechanics. 
     The opposing concave side surfaces  44  may be anatomically contoured with respect to the first and second toes. Concave side surface  44   a  may be anatomically contoured to receive the first toe. Concave side surface  44   b  may also be anatomically contoured to receive the second toe. Referring to the specific embodiment shown in  FIGS. 2 and 3 , concave side surface  44   a  may take the form of a pair of side surfaces  46   a ,  46   b  which are disposed with respect to one another at an obtuse angle. The side surfaces  46   a ,  46   b  are shaped to complement a general anatomical shape of the proximal phalanx and the distal phalanx, respectively, of the first toe. Concave side surface  44   b  may take the form of a pair of side surfaces  48   a ,  48   b  which are also disposed with respect to one another at an obtuse angle. The side surfaces  48   a ,  48   b  are shaped to complement a general anatomical shape of the proximal phalanx and the intermediate phalanx, respectively of the second toe. 
     Contouring the opposing concave sides  44   a ,  44   b  closely to the general anatomical shape of the first and second toes, as described above, may provide the wearer of the interdigit toe piece  32  with the sensation that the first and second toes are securely cradled. Additionally, relative to conventional open styled footwear, where a strap is passed directly and loosely between the first and second toes, the wearer of the interdigit toe piece  32  experiences reduced friction and irritation between the first and second toes. 
     In the embodiment shown in the Figures, the body  32  has a rear concave surface  50 . The rear concave surface  50  is configured, in use, to receive an interdigit web (of skin) disposed between the first and second toes. Cradling of the interdigit web in this way may also contribute to a reduction in friction and irritation to the wearer of the interdigit toe piece  32 . 
     The interdigit toe piece  32  is adapted to receive the forward strap portion  16  of the strap  14 . In the embodiments shown in the Figures, the interdigit toe piece  32  has an aperture  52  extending therethrough. The aperture  52  extends between an upper surface  54  and a lower surface  56  of the body  42 , and also through the footbed inlay body  30 . The positioning of the aperture  52  coincides with the aperture and first connection point  24  located on the sole member  12 . 
     The upper surface  54  of the body  42  may be appropriately shaped to coincide with the contours of the front strap portion  16  and thereby present a streamlined appearance between the front strap portion  16  and the interdigit toe piece  32 . In this way, the front strap portion  16  and the interdigit toe piece may appear to be integrated as a single unit. 
     Referring in particular to  FIGS. 6 to 9 , the article  10  of footwear further includes a cushion  58 . The cushion  58  is integrally disposed with and extends between midsole and heel regions of the sole member  12 , on an inner side  60  thereof, as shown in  FIGS. 6 and 7 . 
     The cushion element  58  has a midsole portion  62  integrally connected to a heel portion  64 . 
     The midsole portion  62  comprises an arched cushion  66 . The arched cushion  66  may take the form of an arch cookie. The term ‘arch cookie’ as used herein refers to a foam insert placed under the insole, designed to support the arch of the foot. The arch cookie may have an adhesive underside to facilitate positioning of the arch cookie on the sole member  12 . 
     The arched cushion  66  is contoured such that, in use, an upper surface thereof supports a medial longitudinal arch of a wearer&#39;s foot. The arched cushion  66  has a first side  68  and a second side  70 . The first side  68  of the arched cushion  66  extends coincidentally along the inner side  60  of the midsole region of the sole member  12 . The second side  70  is shaped to complement and abut the isthmus-shaped section  40  of the footbed inlay body  30 . 
     The heel portion  64  is generally J-shaped or may otherwise curve laterally away from the inner side  60  of the sole member  12  behind where a heel would reside when the article  10  is worn. 
     In this specific embodiment, a first side  74  of the heel portion  64  extends coincidentally along the inner side of the heel region of the sole member  12  and a second side  76  of the heel portion  64  is shaped to complement and abut the bulbous rear portion  38  of the footbed inlay body  30  on which the wearer&#39;s heel would reside. Positioning the heel portion  64  in this way stops the foot sliding in a medial direction and thereby provides medial-varus heel support. 
     The heel portion  64  is also cushioned and contoured to provide the sole member  12  with a lateral camber, as shown in  FIG. 9 . The lateral camber may be between about 4-6 degrees. The lateral camber of this specific embodiment consequently complies with principles of foot biomechanics for effective kinematic foot function. 
     The cushion element  58  may vary in size to fit different sized articles  10  of footwear. The sizing of the cushion element  58  may be based upon the mondopoint system for foot-shoe sizing. 
     The article  10  of open styled footwear and its corresponding sole member  12  may be provided with any one or all of the ergonomic components described herein, including the interdigit toe piece  32 , the footbed inlay  30 , and the cushion  58 . It will be appreciated that such ergonomic components may be particularly beneficial in minimising lower limb musculoskeletal injury and improving comfort performance criteria, in particular for articles of open styled footwear that are worn for recreational pursuits which involve prolonged periods of walking. Particular examples of such articles include, but are not limited to, beach wear footwear, walking sandals, and casual flat-soled footwear. 
     Numerous variations and modifications will suggest themselves to persons skilled in the relevant art, in addition to those already described, without departing from the basic inventive concepts. All such variations and modifications are to be considered within the scope of the present invention, the nature of which is to be determined from the preceding description. 
     In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” and variations such as “comprises” or “comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the apparatus and method as disclosed herein.