Abstract:
A contoured insole especially advantageous for users with medium to high arches is disclosed. It comprises a generally foot-shaped base extending from a heel end to a toe end, which comprises a top surface and a bottom surface. The bottom surface of the base preferably further comprises two indentations formed integrally therein in a forefoot area and a heel area. A forefoot pad and a heel pad are secured to each of said indentations. Preferably, the base is made from a polyurethane foam. The pads are made from rubber or synthetic rubber. A top sheet is coextensive with and secured to the top surface of the base. The top sheet is generally a fabric which preferably has antimicrobial characteristics. In use, the foot of the wearer, with or without a sock or stocking thereon, rests upon the top sheet in the foot-receiving compartment of a user&#39;s shoe.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/358,723 filed Jun. 25, 2010. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       TECHNICAL FIELD 
       [0003]    This invention relates to the field of replacement insoles for shoes. 
       BACKGROUND OF THE INVENTION 
       [0004]    Insoles are inserted in the shoes of a user to provide one or more advantages to to the comfort of the wearer or the support of the foot. Insoles are generally sold in pairs and one of each pair is adapted for use in a right shoe and the other adapted for use in a left shoe of a user. It is advantageous to provide appropriate structure to an insole so that it serves the purposes of the user. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a perspective bottom view of a left insole according to the invention. 
           [0006]      FIG. 2  is a top or foot-side view of a left insole according to the invention. 
           [0007]      FIG. 3  is a bottom or shoe-side view of a left insole according to the invention. 
           [0008]      FIG. 4  is a medial side view of a left insole according to the invention, as referenced in  FIG. 2  as  4 - 4 . 
           [0009]      FIG. 5  is a lateral side view of a left insole according to the invention as referenced in  FIG. 2  as  5 - 5 . 
           [0010]      FIG. 6  is an end view of a left insole from the toe area toward the heel area along line  6 - 6  of  FIG. 3 . 
           [0011]      FIG. 7  is an end view of a left insole from the heel area area toward the toe area along line  6 - 6  of  FIG. 3 . 
           [0012]      FIG. 8  is a cross-sectional view along line  8 - 8  of  FIG. 2   
           [0013]      FIG. 9  is a cross sectional view along line  9 - 9  of  FIG. 2 . 
           [0014]      FIG. 10  is a cross sectional view of the heel area along line  10 - 10  of  FIG. 2 . 
           [0015]      FIG. 11  is a cross sectional view along line  11 - 11  of  FIG. 2 . 
           [0016]      FIG. 12  is a cross-sectional view along line  12 - 12  of  FIG. 2 . 
           [0017]      FIG. 13  is a cross sectional view along line  13 - 13  of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    An insole advantageous for users having a medium to high arch is herein disclosed that provides arch and heel support to users in need of such support. The insole has a bottom (shoe side) and a top (foot side) and comprises a base having a contoured shape which receives and supports the foot of the user. The insole is intended to be used inside a shoe and the bottom side thereof will contact the interior of a shoe after insertion therein. In many cases, the insole will be used to replace an insole in the shoe. 
         [0019]    The insole base has a heel end, a toe end, a lateral side and a medial side, said sides extending from said heel end to said toe end. The lateral side lies adjacent the outer side of a user&#39;s foot in use and the medial side lies adjacent the inner side of a user&#39;s foot in use, including the arch of the foot. Accordingly, the contoured shape includes an integrally formed raised arch support which extends generally upwardly on the medial side of the insole. This upward extension allows the raised arch support to lie adjacent to a user&#39;s foot arch during wearing. 
         [0020]    The base has a base top surface and a base bottom surface. The base defines a heel area adjacent said heel end, a contoured arch support area adjacent said medial side, a midfoot area adjacent said contoured arch support area extending essentially horizontally from said contoured arch support area to said lateral side, a forefoot area adjacent said contoured arch support area and said midfoot area, and extending vertically to said toe end. 
         [0021]    The base is preferably made from a lightweight resilient material which is capable of being molded into the desired shape and which provides the desired support and cushioning. A preferred material is polyurethane foam. Preferably, a polyurethane foam (“PU”) having a hardness of 40 Asker C+/−3 and a density of about 0.41 g/ml +/−3 is employed. PU is preferred for the base material as it adapts to providing the insole with a deep heel cup which adheres to a top sheet intended to be worn next to the foot of the user. 
         [0022]    PU is able to adhere to top cloth material and avoid separation of the top sheet from the base material. 
         [0023]    The heel area of the base bottom surface preferably defines a heel cushion indentation for receiving a heel cushion, and in such case a heel cushion is disposed therein. 
         [0024]    A preferred heel cushion is made from a neoprene or synthetic rubber layer which is a polymer of polychloroprene. 
         [0025]    The forefoot area of the base bottom surface preferably defines a forefoot indentation for receiving a forefoot cushion and in such case a forefoot cushion is disposed therein. 
         [0026]    A preferred forefoot cushion is made from a neoprene or synthetic rubber layer which is a polymer of polychloroprene. 
         [0027]    The midfoot area of the base preferably defines a resilient area comprising an indentation which extends upwardly from said base bottom surface to said base top surface. From the vantage point of the base top surface, said resilient area is convex and from the vantage point of the base bottom surface, said resilient area is concave. The resilient area functions as a metatarsal pad to distribute pressure from the ball of a user&#39;s foot and assist in relieving forefoot pain. In use, the central part of the plantar fascia or the plantar aponeurosis of a user&#39;s foot rests on said resilient area. 
         [0028]    In a preferred embodiment, said resilient area is molded into said base during manufacture. The convex structure lies under the foot during use and provides cushioning and support. 
         [0029]    The insole preferably further comprises a top sheet having a top sheet bottom surface secured to said base top surface and a top sheet upper surface which contacts the foot of a user during use. Preferably, the top sheet is made of a low-friction fabric which prevents blisters on the user&#39;s foot. The top sheet may also contain an antimicrobial treatment in order to keep bacteria from multiplying and therefore reduce odor. A suitable treatment is Silpure® antimicrobial treatment (Thomson Research Associates, Inc., Ontario, CA.) 
         [0030]    The base bottom arch area preferably defines a plurality of curvilinear indentations positioned from adjacent said midfoot area to said medial side. Lengthwise, said curvilinear indentations extend from approximately a border between said forefoot area and said arch/midfoot area to a border between said heel area and said arch/midfoot area. 
         [0031]    The curvilinear indentations are preferably molded into the base during manufacture. They function to promote polyurethane material flow in the area of the midfoot while assisting to minimize voids caused by air entrapment. The curvilinear indentations in the arch area also allow the arch area to collapse to fit the shoe thus providing a more accommodative design. 
         [0032]    Insole production can be accomplished by an open-pour molding process. The process consists of pouring mixed polyurethane into an open mold. Once poured in the mold, the polyurethane mixture will expand to fill the cavity. Once cured, the base insole is removed from the mold. The forefoot cushion and heel cushion if employed can be secured to the indentations by adhesive or can be secured in place during the polyethylene pouring operation. Bonding occurs to a fabric that is bonded to the forefoot cushion or the heel cushion. 
         [0033]    As an example, approximate dimensions are given for a men&#39;s size 9 insole. Length and width of the insole are 28.1 cm (11.063 inches) and 9.7 cm (3.813 inches). The length and width will vary according to the shoe size for which the insole is intended. 
         [0034]    The total thickness of the insole can range from 6.8 millimeters near the toe area to 12 millimeters in the arch area. Arch height is about 15 millimeters. The forefoot and heel cushions have a thickness of approximately 4.0 millimeters. 
         [0035]    The preferred depth of the heel cup which is measured from the top side of the insole near the center of the heel area vertically to the top of the upraised heel area or heel raised edge is approximately 15-16 millimeters. 
         [0036]    Now referring to  FIG. 1  which is a perspective view of the bottom (shoe side) of an insole according to the invention. A left insole is illustrated and it can be easily envisioned that a right insole would be a mirror image of the left insole illustrated. Insoles are generally sold and used in pairs, each pair comprising a right and a left insole. Insole ( 10 ) of the insole has been divided for discussion into a heel area ( 10 A) adjacent said heel end, an contoured arch support area ( 10 B) adjacent said medial side, a midfoot area ( 10 C) adjacent said contoured arch support area ( 10 B) extending essentially horizontally from said contoured arch support area ( 10 B) to said lateral side, and a forefoot area ( 10 D). 
         [0037]    A heel cushioning pad ( 20 ) and a forefoot pad ( 22 ) are shown secured to indentations in the bottom side of the base. Forefoot pad ( 22 ) is secured adjacent said contoured arch support area ( 10 B) and said midfoot area ( 10 C) and extending vertically to said toe end of the insole. Heel cushioning pad ( 20 ) is secured in an indentation in the heel area ( 10 A) of the insole. Pattern ( 24 ) is visible in this view in midfoot area ( 10 C). A metatarsal indentation ( 26 ) is also located in midfoot area ( 10 C). A plurality of curvilinear indentations ( 28 ) are positioned from adjacent said midfoot area ( 10 C) to said medial side. 
         [0038]    Now referring to  FIG. 2 , which illustrates the top (foot side) of an insole according to the invention, metatarsal indentation ( 26 ) projects upwardly from the bottom of the insole to the top side. Raised arch support ( 30 ) is along the medial side of the insole. The insole is contoured to define upraised heel area ( 32 ) and lateral raised edge ( 34 ). 
         [0039]      FIG. 3  illustrates the bottom shoe side of the insole, and metatarsal indentation ( 26 ), heel cushioning pad ( 20 ), forefoot pad ( 22 ), curvilinear indentations ( 28 ) and pattern ( 24 ) are clearly visible. 
         [0040]    Referring to  FIG. 4  illustrating medial side view, curvilinear indentations ( 28 ) and raised arch support ( 30 ) are illustrated. Also illustrated are forefoot pad ( 22 ), base ( 23 ) and top sheet ( 25 ). Base ( 23 ) extends from the heel region to the toe region. Top sheet ( 25 ) is secured to the upper surface of said base and is contiguous therewith. 
         [0041]    Raised arch support ( 30 ) extends upwardly so it will lie adjacent a user&#39;s foot arch during use and provide added comfort. 
         [0042]    Now referring to  FIG. 5  which shows lateral side view of an insole according to the invention, a portion of base ( 23 ) and top sheet ( 25 ) on raised arch support ( 30 ) are illustrated. Forefoot pad ( 22 ) which lies in an indentation in base ( 23 ) is also visible. 
         [0043]    Now referring to  FIG. 6  which is an end view from the toe end looking toward the heel end, upraised heel area ( 32 ) is visible at the heel end, raised arch support ( 30 ) is seen on the medial side. Forefoot pad ( 22 ), base ( 23 ) and top sheet ( 25 ) are visible. 
         [0044]    Upraised heel area ( 32 ) is adapted generally to receive the heel area of a user&#39;s foot. In this view the contour of upraised heel area ( 32 ) is visible. The cup shape allows for extra comfort and security to the heel of the foot. 
         [0045]      FIG. 7  is an end view from the heel area looking toward the toe area. From this view, one can see base ( 23 ) at upraised heel area ( 32 ), curvilinear indentations ( 28 ) on the bottom side of the insole, top sheet ( 25 ) in the area of raised arch support ( 30 ) and on medial top side. 
         [0046]    Also shown is a heel cup depth ( 35 ) which is measured from the top sheet ( 25 ), approximately at the center of the heel area ( 10 A), vertically up to the heel raised edge ( 36 ). In a preferred embodiment, heel cup depth ( 35 ) is approximately 15-16 millimeters. 
         [0047]      FIGS. 8-13  show cross sections of the lines denoted in  FIG. 2 . 
         [0048]      FIG. 8  illustrates a cross section of metatarsal indentation ( 26 ) from line  8 - 8  of  FIG. 2 . 
         [0049]      FIG. 9  is a cross section along line  9 - 9  of  FIG. 2 . One can see the cross section of heel cushioning pad ( 20 ), forefoot pad ( 22 ), base ( 23 ) and top sheet ( 25 ). Upraised heel area ( 32 ) is also illustrated in cross section. 
         [0050]      FIGS. 10-13  show cross-sections of the insole at  10 - 10 ,  11 - 11 ,  12 - 12  and  13 - 13  of  FIG. 2  respectively. When compared one to another, the change in shape (both curve and thickness) at different sections of the insole can be seen. The thickness is typically much greater in the arch area of the foot as shown in  FIG. 2  and  FIG. 12 . The cup or dented shape of the upraised heel area ( 32 ) is best shown in  FIG. 2  and  FIG. 10 .