Patent Publication Number: US-2006005426-A1

Title: Elastic overshoe with modular sole pads

Description:
This application is a continuation-in-part of utility patent application Ser. No. 10/889747 filed Jul. 12, 2004. 
    
    
     FIELD OF THE INVENTION  
      The present invention relates generally to overshoes (shoe covers).  
     BACKGROUND  
      Elastic overshoes of various types have been known for decades. They are typically worn to keep the wearer&#39;s feet warm and dry during cold and/or wet weather, but are also used in hospitals, restaurants, factories, and other areas where floors may be slippery.  
      Previously known overshoes generally comprise a unitary construction, such as, for example, that found in a continuous molded rubber product. This is done to facilitate construction of the overshoe using a single, inexpensive molding process. Unfortunately, in such cases both the upper portion and the sole are necessarily made of the same material, which is then intended to satisfy the competing needs of elasticity and grip.  
      One solution to these competing needs is to fashion the sole with a raised tread pattern. Such tread patterns are designed to improve traction and thus reduce the likelihood of the wearer accidentally slipping. Although somewhat effective, the inherent tradeoff resulting from the use of a given material usually means that either the overshoe is insufficiently elastic (requiring manufacture and stocking of many different sizes), or the overshoe has insufficient traction.  
      There is yet a third tradeoff, namely that materials satisfying both elasticity and traction can have undesirable durability characteristics. Among other things previously known overshoes tend to wear out prematurely, rip, or in some other manner become dysfunctional.  
      Thus, there is still a need for an overshoe that has adequate elasticity, as well as enhanced slip resistance, and high durability.  
     SUMMARY OF THE INVENTION  
      The present invention provides methods and apparatus in which an elastic overshoe includes an upper portion, a sole portion, and at least one gripping pad, where the upper portion and the sole portion have an elasticity greater than that of the pad.  
      The entire overshoe can advantageously be manufactured from rubber or other polymers. Although all suitable materials are contemplated, the upper and sole portions are preferably one continuous piece of thermoplastic rubber, while the pad (or pads) is/are formed of nitrile rubber. Various different thermoplastic rubbers and thermoplastic elastomers, as well as other elastic materials, are also contemplated.  
      In preferred embodiments an overshoe has a first pad disposed at a ball portion of the sole, and a second pad disposed at a heel portion of the sole. Both pads are affixed to the sole portion using glue, or some other bonding mechanism. Since the ball and heel of the overshoe are separated from one another, the intervening section of the sole continues to have relatively high elasticity.  
      The first and second pads can advantageously have a tread pattern that enhances slip resistance, and indeed the material or materials used for the pads can be chosen in part for improved wear and slip resistance.  
      Especially preferred embodiments have three or more sole pads. For example, a pair of sole pads can be positioned under the ball of the foot, and another pair of sole pads can be positioned under the heel of the foot. Separation of the members of each pair by an elastic underlayer provides yet further accommodation for different sized shoes. Significantly, providing different materials and/or tread patterns for adjacent pads in a pair can improve slip resistance in multiple situations. For example, one pad could provide slip resistance for grease, while another pad could be adapted to provide slip resistance on ice.  
      Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.  
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       FIG. 1  is a top perspective view of an exemplary embodiment the elastic overshoe of the present invention; and  
       FIG. 2  is a bottom perspective view of the elastic overshoe of  FIG. 1 , showing the first and second pads thereof.  
       FIG. 3  is a perspective view of an elastic overshoe having a pair of front sole pads, and a pair of heel sole pads.  
       FIG. 4  is a bottom view of perspective view of a set of eight sole pads.  
       FIG. 5  is a bottom view of a package that includes a set of overshoe pads removably coupled to a backing sheet. 
    
    
     DETAILED DESCRIPTION  
      In  FIGS. 1 and 2 , an overshoe  1  generally comprises an upper portion  10 , a sole portion  20 , a first pad  30 , and a second pad  40 .  
      With particular reference to  FIG. 1 , the upper portion  10  is configured to slip over a regular shoe and to fit tightly thereabout. To that purpose the upper portion  10  is advantageously molded to fit overtop of a typically shaped athletic or dress shoe. Various alternative embodiments are contemplated for women&#39;s shoes, such as uppers that have a pointed front, but such embodiments are not preferred. Upper portion  10  is also advantageously configured to be generic with respect to footedness, i.e. the same overshoe would work equally well with a right foot and a left foot. Among other things, that feature reduces manufacturing and inventory costs. As with other overshoes, the upper portion  10  slips over a shoe (dress shoe, casual shoe, athletic shoe or other footwear) by inserting the shoe into opening  13 , and pulling the overshoe onto the shoe. The overshoe may be removed by simply pulling it off of the shoe.  
      The upper portion  10  and sole portion  20  are preferably one continuous piece of elastic material. As used herein, the term “elastic” refers to something that stretches to a significant extent, and then substantially returns to its original shape. Preferred elastic materials include various forms of rubbers or other polymers, including especially thermoplastic rubbers. Various different thermoplastic rubbers and thermoplastic elastomers are suitable.  
      Alternatively, the upper portion  10  and sole portion  20  can be comprised of different materials, or different blends of the same materials, and then attached by adhesives, ultrasonic welding, or by any other suitable methods. As used herein, the term “adhesive” includes all manner of adhering substances, regardless of whether they are natural or artificial, and regardless of whether they form a temporary or permanent bond. In production versions a manufacturer would likely overmold the pad(s) into the sole, or affix the pad(s) using a mechanical attachment such as a retaining button used in beach foot thongs, where the thong is attached through the sole and is anchored in place by a small portion of material fanning out the bottom the sole.  
      With particular reference to  FIG. 2 , a first pad  30  is disposed at the ball  17  of the sole portion  20 . Similarly, a second pad  40  is disposed at the heel  18  of sole portion  20 . Optionally, an arch  14  is formed in the bottom or sole  20  of the overshoe, intermediate the toe  17  and the heel  18 .  
      The first pad  30  and the second pad  40  can be formed of any suitable material or materials that provide(s) advantageous wear and slip resistance. The presently preferred material comprises nitrile rubber.  
      The first pad  11  and the second pad  12  may be attached to the upper portion  10  by any suitable means. For example, the first pad  11  and the second pad  12  may be attached to the upper portion  10  by glues, adhesives, ultrasonic welding, overmolding, retaining button, and so forth. Alternatively, the first pad  11  and the second pad  12  may be molded into the upper portion  10 . This may, for example, be accomplished by a co-molding process wherein the first pad  11  and the second pad  12  are provided as inserts for the mold with which the upper portion  10  is fabricated.  
      The area of the sole  16  located intermediate the first pad  11  and the second pad  12 , at approximately the arch of the wearer&#39;s foot, is advantageously comprised of a substantially elastic material, which assists in allowing the overshoe to accommodate a variety of shoe sizes.  
      It is also worthwhile to appreciate that any desired number of materials may be used to form the upper portion  10 , the first pad  11 , and the second pad  12 . The first pad  11  can be made from a different material with respect to the second pad  12 . Further, the first pad  11  and/or the second pad  12  may be formed of more than one material.  
      The overshoe of the present invention need not be limited to two pads. Any desired number of pads may be utilized. Thus, an overshoe of the present invention may comprise 1, 2, 3, 4, 5, 6, 7, 8 or more pads.  
      The upper portion  10  may alternatively be configured such that it covers a larger portion of a regular shoe that would be covered by the overshoe of  FIGS. 1 and 2 . The upper portion  10  may alternatively be configured to cover all or a portion of a shoe or boot.  
      As with the upper portion  10 , sole portion  20  is advantageously configured to be generic with respect to footedness, i.e. the same overshoe would work equally well with a right foot and a left foot. This has the advantage of requiring only a single mold shape. It has the additional advantage of easily allowing a substitute overshoe to replace a damaged regular shoe without consideration as to which (right or left) regular shoe it replaces.  
      Preferably, one size of the overshoe of the present invention fits a plurality of sizes of regular shoes. It is contemplated that two sizes of the overshoe of the present invention will fit most of the adult shoe sizes.  
      In  FIG. 3  an overshoe  300  generally includes a body  310 , a front or “ball” pair of sole pads  310 , and a rear or “heel” pair of sole pads  320 . The body  310  advantageously comprises a single piece of relatively elastic plastic molded from a suitable material as discussed above, and provides a waterproof barrier to water disposed at the sole of the overshoe. The front pair of sole pads  310  comprises left  310 A and right  310 B members that can be substantially identical with respect to material and tread, or can be different from one another. The same is true of the left  320 A and right  320 B members of the rear sole pads  320 . Thus, each of the four pads  310 A,  310 B,  320 A, and  320 B can have the same or different characteristics from each of the other pads. Thus, one or more of the pads could provide slip resistance for grease, while another one or more of the pads could be adapted to provide slip resistance on ice.  
      In  FIG. 4 a  set of overshoe pads  400  comprises four front  410 A-D and four rear  420 A-D pieces. Here again, the separation of the pieces can readily accommodate different or similar materials and tread patterns. The concept should be viewed here in its most general aspect. The various figures should be taken to mean that overshoes are contemplated that have 2, 3, or 4 front sole pads, but only a single rear sole pad. All other reasonably viable embodiments are contemplated as well, including for example an overshoe that includes only a single independently applied sole pad, most likely to either the ball or the heel sole area.  
      As discussed above, it is contemplated that the various sole pads can be affixed to the body in any suitable manner, including by gluing, sonic welding, and so forth. It is even contemplated that sole pads could be replaceable by an end user, (i.e. consumer). To that end, individual pads could be packaged in boxes or otherwise, so that one may have a box of left front pads for slip resistance on grease, and a box of right front pads for slip resistance on grass.  
      Also contemplated are sets of sole pads affixed to a peel off backing, as in  FIG. 5 . There, a set of pads  500  generally includes a backing sheet  505 , and peel off pads  510 A-B and  520 A-B. Each of the pads can advantageously have a pre-applied adhesive layer on their backsides. The adhesive can allow removal of the pad from the overshoe body, or more preferably, the adhesive is such that it bonds the pad to the overshoe body in a manner that is permanent (i.e. cannot be removed without damaging at least one of the pad and the body). In  FIG. 5  the pads and backing sheet are included in a cellophane package  530 , with information  532  regarding type of slip or wear-resistance provided, and/or instructions on use of the pads. Alternative packaging can include a box containing a plurality of pads. It is also contemplated that the adhesive need not be pre-applied. For example, a kit can contain overshoe bodies, pads, and a tube of adhesive. Where the adhesive is pre-applied, a kit can include a pair of overshoes as in  FIG. 3 , as well as pads as in FIGS.  4  or  5 .  
      In addition to the above-mentioned advantages, the use of independently applied sole pads either (a) during manufacture or (b) as sold to consumers allows considerable interchange-ability, so that the same pads could be applied to different size overshoe bodies, and so that worn out sole pads can be replaced. The strategy of using independently applied sole parts is also contemplated to reduce the need for large inventories, and to reduce manufacturing and storage costs.  
      Thus, specific embodiments and applications of improved overshoe have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.