Abstract:
The present invention relates to a multi-density lasting board for a shoe. The multi-density lasting board comprises at least a first density foam and a second density foam contained substantially within the first density foam. The second density foam is placed to provide additional cushion or support to selected portions of the foot based on basic biometrics, anatomy, and individual comfort.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to shoes and, more particularly, to a sport shoe with a multi-density lasting board.  
       BACKGROUND OF THE INVENTION  
       [0002]     Shoes have been specialized and improved for years. Currently, shoe manufacturers and designers provide specialized shoes for many activities, such as, for example, running shoes, tennis shoes, cycling shoes, walking shoes, and cross-trainers. These shoes can be designed to respond to particular pressures and hot spots for the assumed usage.  
         [0003]     However, shoe soles and/or inserts are typically designed as a largely consistent piece of rubber, typically a foam, or gel. While the consistent sole may be shaped and conformed to an individual&#39;s foot anatomy and is generally satisfactory, the cushion or support provided by the sole does not take into account different actions of the foot. As used in this application, the term cushion could mean more or less cushion depending on context. For example, during running, the metatarsal and heel portions of the foot are generally exposed to higher impact forces than the arch or instep. But the cushion or support provided by conventional shoe soles is uniform, despite this difference. Further, the toes are subject to pronation, but the sole or insert does not alter its cushion or support to help combat pronation.  
         [0004]     In light of the above, it would be desirous to develop a multi-density lasting board or insert to provide varying cushion or support over the foot.  
       SUMMARY OF THE INVENTION  
       [0005]     To attain the advantages and in accordance with the present invention, a shoe is provided. The shoe comprises a sole and an upper forming an interior foot portion and an exterior portion. A lasting board formed to overlay a sole portion in the interior foot portion comprises a first density foam portion and a second density foam portion. The second density is substantially contained in the first density foam portion and provides different cushioning over the sole.  
         [0006]     The foregoing and other features, utilities and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0007]     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention, and together with the description, serve to explain the principles thereof. Like items in the drawings are referred to using the same numerical reference.  
         [0008]      FIG. 1  is a topside elevation of a multi-density shoe insert constructed in accordance with an embodiment of the present invention;  
         [0009]      FIG. 2  is a cross-sectional elevation view of a shoe insert constructed in accordance with  FIG. 1 ; and  
         [0010]      FIG. 3  is a flowchart illustrative of one method of construing a multi-density shoe insert consistent with the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0011]     The present invention will be described with reference to  FIGS. 1-3 . While the present invention is shown and described with regard to a running shoe, one of ordinary skill in the art would recognize on reading the disclosure that alternative shoes styles could use the invention described herein, and the use of a running shoe is exemplary and non-limiting. Other styles of shoes that would benefit from the present invention include, without limitation, cycling shoes, sport cleats, basketball shoes, tennis shoes, and walking shoes  
         [0012]      FIG. 1  shows a top elevation view of a multi-density lasting board  100  constructed in accordance with the present invention. While described as a lasting board fused to the sole during manufacturing (see  FIG. 3  form more details on construction), one of ordinary skill in the art would recognize on reading the disclosure that board  100  could be designed as an insert to be inserted into a shoe subsequent to manufacturing. Such an insert could be inserted and permanently attached or inserted such that it is removable.  
         [0013]     Board  100  comprises a heel portion  102 , a mid-shoe portion  104  or midsole portion, and a toe box  106 . Board  100  comprises at least two, but in this example, three different density foam sections. Largely, board  100  comprises a first density foam  108 . Board  100  also comprises a second density foam  110  in the high impact areas of heel  102  and the metatarsal section of toe box  106 . In this case, a third density foam  112  is located at the ball of the foot in toe box  106 . As shown, second density foam  110  and third density foam  112  are substantially contained in first density foam  108 .  
         [0014]     Foams  108 ,  110 , and  112  can be comprises of the same or different types of foams. Some types of foams include ethyl vinyl acetate foams, polyurethane forms, neoprene foams, and the like. All the foams could be open or closed cell foams as a matter of design choice. Moreover, the foams could be designed with moisture removal devices, such as, for example absorbents  114  or wicking materials  116 . Absorbents  114  and wicking materials  116  are generally known in the art and will not be further explained herein. See for example, U.S. Pat. No. 6,493,966, titled S OLE  S TRUCTURE FOR A  S HOE OR AN  I NNER  S OLE , issued Dec. 17, 2002, to Braun, incorporated herein by reference and U.S. Pat. No. 6,432,504, titled C OMPOSITE  T EXTILE  F ABRIC HAVING  M OISTURE  M ANAGEMENT , issued Aug. 13, 2002, to Yeh, incorporated herein by reference.  
         [0015]     The actual locations of foams  110  and  112  (or more or less depending on the number of different density foams desired) are based on simple biometrics generally known in the art. Based on the biometrics, such as anatomy, gait, and the like, higher or lower density foams may be located. Additionally, the increase or decrease in density can be calculated from the same biometrics. In the positions shown, foam  108  is a first density, foam  110  is a second lower density, and foam  112  is a third lowest density. In generally, the relatively higher density foams are placed under those sections of the foot that collapse, such as the toes, to provide added support to those areas. Relatively lower density foams are placed under more rigid areas of the foot, such as the heel to provide cushion. Using softer, less dense foams under areas of the foot that are rigid in combination with harder, more dense foams under the collapsing areas, the multi-density lasting board assists in guiding the foot through the gait cycle, heel to toe action. In some applications, it maybe desirous to have higher density foams under rigid areas of the foot and/or lower density foams under collapsible areas of the foot. Board  100  shows placement of foams  108 ,  110 , and  112  assuming a running shoe. If, for example, board  100  was for a cycling shoe, foam  110  is heel portion  110  and may be removed because the heel is not subject to high impact. Placement of the different density foam is related in part to the use of the shoe.  
         [0016]     Referring now to  FIG. 2 , a cross-sectional view of lasting board  100  is shown. In this case, lasting board  100  is shown mounted on a sole  202  of a shoe, including upper  206  (of which only a portion is shown). Sole and upper  206  define an internal cavity  208 . Lasting board  100  is coupled to sole  202  using an adhesive layer  204 . Adhesive layer  204  is generally known in the art and will not be further explained herein. Adhesive layer  204  can be a number of different materials, but it has been found that general purpose footwear cements that are heat activated and polyurethane based work well.  
         [0017]     Referring now to  FIG. 3 , a flowchart  300  is provided illustrative of an method of constructing the lasting board described above. First, the lasting board is constructed out of a first density foam, step  302 . One or more portions of the lasting board are removed, such as by die cutting, in locations where a second density foam (or a third density foam, etc.) is desired, step  304 . For example, in  FIG. 1 , a section consistent with second density foam  110  was removed from heel portion  102  of lasting board  100 . Other density foam sections are constructed to be inserted into the portions removed in step  304 , step  306 . The other density foam sections are inserted into the removed portions, step  308 , and fused to the first density foam, step  310 , such as by a heat activated adhesive or the like.  
         [0018]     Optionally, a section of second density foam could be removed, such as by die cutting, and a third density foam, or the first density foam, could be inserted into the second density foam as desired.  
         [0019]     Lasting board  100  could be sold as an insert to be inserted into a shoe by a user. Optionally, however, lasting board  100  is placed on sole  202 , step  312 , and adhered to sole  202  using an adhesive  204 , step  314 .  
         [0020]     While the invention has been particularly shown and described with reference to an embodiment thereof, it will be understood by those skilled in the art that various other changes in the form and details may be made without departing from the spirit and scope of the invention.