Abstract:
A shoe attachment device having a front metatarsal covering shell and a vertical lip used for wedging against a hand truck wheel axle in order to pull the hand truck by foot without straining the foot or toes. Holes formed in the metatarsal shell allow the device to be securely attached to a laced shoe via shoelaces.

Description:
BACKGROUND 
       [0001]    The present invention generally relates to shoe attachment devices, and it is specifically directed to a device that is attachable to the metatarsal area of a laced shoe so as to assist its wearer in using a leg to pull a loaded hand truck out from underneath a heavy load placed thereupon without subjecting the foot to undue blunt trauma or potentially injurious strain. 
         [0002]    Foot injuries not caused by running or jumping are, typically, caused by any one of three things: (a) accidental striking of the metatarsal or toe area of the foot by falling objects; (b) accidental striking of the heel or toe area of the foot against lying or erected objects; or (c) deliberate striking of the metatarsal or toe area of the foot against sporting balls and other objects. Protecting the foot against these typical causes of injury is achieved through either shoe construction or use of an extraneous (to the shoe) protective device. 
         [0003]    Shoe designs for protecting against injuries caused by either of the two aforementioned types of accidental foot striking events often feature metal or hard plastic reinforced toe and/or heel portions of the upper, or “vamp,” part of the shoe. In some cases, these protective shoe uppers also have built into them rigid devices that cover the metatarsal area of the foot. One such example is found in U.S. Pat. No. 7,328,526 to Peterson. Peterson discloses a shoe upper having a metatarsal guard formed within it. The guard is a rigidly flexible convex piece that extends from the rear of the wearer&#39;s toes to the top of the wearer&#39;s instep. Shoes and boots having uppers that are configured to be protective are standard attire for industrial workers, for example. However, because of their rigidity and, typically, their non-breathability, these kinds of footwear are generally preferred for use in the physical labor environment, but not so much for casual wear and certainly not for use in athletic activities in which the risk of the foot impacting anything other than the ground is minimal (e.g., running, weightlifting, etc.). Consequently, the prior art is replete with devices that are removably attachable to shoes for the purpose of protecting users&#39; feet from injuries caused by any of the aforementioned three types of foot striking events. 
         [0004]    For example, U.S. Pat. No. 8,959,801 to Siragusa discloses an ankle and foot protector device for attaching to a hockey skate. The Siragusa device is formed by a generally rectangular instep protector pad that covers the length of the instep and a transversely oriented ankle protector pad. Pairs of laterally spaced holes formed in each pad that allow skate laces to be threaded through them, coupled with a strap of hook and loop fastener material, permits the device to be securely mounted to the skate. The two pads are configured to be effective in protecting a wearer&#39;s foot from the high impact of a flying hockey puck. However, they, theoretically, could be mounted to a different type of footwear to protect the foot in other contexts. 
         [0005]    Nevertheless, despite the ample number of existent foot protection devices that are configured to prevent foot injury caused by any of the three common types of foot impact events described above, that the present inventor is aware, there is no prior art device configured specifically to prevent the type of foot discomfort and injury that might be result from removing loads from a hand truck in a particular manner. 
         [0006]    A common type of hand truck, or “dolly,” is a two-wheeled, L-shaped apparatus that features a horizontal, load-supporting platform and axle-mounted wheels, at its lower end, which are connected, by a vertical support structure, to one or two handles situated at its upper end. The purpose of a dolly is to transport boxes and other items that are too heavy or too large to be simply lifted and carried to a destination without enormous physical strain and with much greater efficiency than carrying them by hand. This is accomplished by placing a load to be hauled atop the dolly platform and using the handle(s) to rock the apparatus backward so that the platform and load are rotated off the ground—causing the vertical support structure and the platform to cradlingly support the load while only the wheels are contacting the ground. 
         [0007]    Often, with heavier loads, it is helpful for a user to place his or her foot atop the wheel axle in order to gain leverage when rocking the dolly backward to lift its loaded platform. Using the foot in this manner is usually non-problematic because the sole of the shoe dampens the impact between the bottom of the foot and the dolly&#39;s steel axle rod. However, the same cannot be said for the foot maneuver that is often employed to remove the load from the dolly platform upon arriving at the drop-off destination at the end of the haul. More specifically, in effort to be more time efficient, if not to simply to avoid the physical arduousness of removing the load item(s) from the dolly platform by hand, one might be inclined to simply pull the dolly such that its ground-resting platform slides out from underneath the still sitting load that has a bottom surface area which extends beyond the surface area of the dolly platform. And since pulling at the vertically higher handle(s) would generate torque that would, initially, cause the platform to vertically lift, rather than horizontally slide, one might use a foot and leg to pull horizontally on the dolly at its lower end. This can be accomplished by placing a foot underneath the wheel axle and lifting the toes upward so that the axle is wedged into the crease formed at the meeting of the front metatarsal area of the foot and the toes—rendering the toes a vertical barrier against the axle in order that leg muscles, rather than upper body muscles, are exerted to deliver the pulling force needed to withdraw the horizontal platform from underneath the heavy load. 
         [0008]    For persons in the ground freight and product distribution industries who routinely use dollies to move heavy stacks of boxes and other items and who must work quickly, this leg-pulling technique is often used repeatedly to unload dollies. Unfortunately, the resulting blunt trauma sustained by the more tender top of the foot can cause painful bruising, fatigued foot and calf muscles and even more debilitating injury. However, again, the present inventor is not aware of any shoe-mountable aids for alleviating pressure on the foot and reducing the discomfort and risk of injury caused by this dolly pulling maneuver. More specifically, while many of the prior art protective devices may be configured so as to dampen any impact that might occur between the metatarsal area of the foot and a dolly axle, they are not configured to be able to hook or cradle the axle without the wearer having to curl his toes upward and around the axle in order that toes become a somewhat vertical support that presses against the axle and allows the leg to pull the lower end of the dolly such that the dolly platform may simply be slid out from under its load, rather than be tilted into lifting the load from the ground. 
         [0009]    Consequently, the present inventor appreciates a need for a device that: (1) can be easily and securely attached to a laced shoe; (2) enables a user to use his leg to apply pulling force to the wheel axle of a dolly without having to curl his entire foot or toes upward to cradle the axle; and (3) is configured such that it minimizes the likelihood that that leg pulling motion causes discomforting or injurious strain to be placed on the user&#39;s foot. The present invention for a shoe-mounted dolly pulling device substantially fulfills these needs. 
       SUMMARY 
       [0010]    In order for a dolly operator to separate a large load from a dolly platform by removing the dolly from the load, rather than by removing the load from the dolly, the operator must pull the dolly horizontally toward himself. More specifically, he must pull on the dolly at its lower end and not its upper, handle end. That is because, if the pulling force is applied at the upper end of the dolly, the weight of the load will cause the dolly wheels to act as a fulcrum, and the platform will rotate vertically upward, rather than it sliding horizontally toward the operator&#39;s body. Therefore, to avoid the discomfort, upper body strain and potential back injury that might result from crouching and pulling on the lower end of the hand truck with the hands, a dolly operator will typically engage the dolly wheel axle with one of his feet and use that leg to pull the lower end of the dolly toward him—allowing bottom surface area of the load that extends beyond the dolly platform to engage the ground and resist sliding along with the platform due to ground friction. Although a time saving maneuver, repeatedly doing this can greatly strain the delicate toe and foot muscles and the lower leg muscles that must be exerted to keep the axle cradled within the crease formed at the meeting of the front metatarsal and phalangeal regions of the foot and to deliver sufficient pulling force to slide the dolly while the axle presses against the toes. This repeated action can also strain, and potentially rupture, the Achilles tendon, much less cause severe foot bruising and soreness. 
         [0011]    Therefore, it is an object of the present invention to provide a device that, when attached to a shoe, is configured to enable its wearer to perform the aforementioned leg pulling technique on a loaded dolly without even utilizing many of the same foot and leg muscles—at least not to any great extent—that would be exerted without the aid of the present device. In one aspect of the invention, the present device is formed by a convexly-shaped metatarsal guard that inserts into a shoe to fit atop the front metatarsal area of the foot and an upward extending lip that resides at the front end of the guard to give the device an L-shaped profile. So, instead of the wearer&#39;s foot and toes having to cradle the dolly axle, the device hooks around the axle with the lip forming a vertical structure that presses against the axle when the sole of the foot is held parallel to the ground and the foot is drawn along a horizontal plane away from the load. As a consequence, the user does not have to curl his toes upward or keep any muscles of the metatarsal or toes tensed in order to maintain that foot posture against heavy resistance imposed by the dolly axle. This significantly reduces strain on the foot muscles and Achilles tendon. As another consequence, the greatest resistance force imposed by the dolly axle (due to the weight of the load atop the dolly platform) is applied directly the device lip and not to the top of the foot. 
         [0012]    It is another object of the invention to eliminate the foot bruising that currently occurs along the area of contact between the foot and the dolly axle when a dolly operator uses a leg to pull the dolly from underneath a load. In another aspect of the invention, the present device features resilient padding material underneath (on the foot side of) the metatarsal guard and the lip. Therefore, when the device is torqued by its lip being pressed against the axle, resilient material, not the rigid material that forms the metatarsal guard and the device lip nor the metal of the dolly axle, presses against the foot. Because the impact that is applied to the foot is both (1) softened by the padding material and (2) distributed over much, if not all, of the padded undersides of the lip and metatarsal guard (a composite surface area that is significantly broader than is the shoe surface area that would otherwise be in direct contact with the dolly axle), bruising is much less likely to occur than if same maneuver is performed without the present device. 
         [0013]    Finally, it is another object of the present invention to be so unencumbering to wearers of casual and athletic shoes that, once installed onto a laced shoe, the user will not feel compelled to ever remove the present device in order to wear the shoe free of the device when not operating a dolly. In other words, the object is for the device to be immaterial to the general functionality and performance of the shoe to which it is attached so as to obviate the need to detach the device or change shoes after dolly use and before engaging in other activities. In another aspect of the invention, present device is lightweight, its metatarsal covering portion is contoured to generally conform to the foot, its lip portion has a fairly low profile and its underside is cushioned. Furthermore, the laterally outer areas of the metatarsal covering portion have apertures formed within them to allow shoe laces to be threaded through the device to securely anchors it to the forward metatarsal area of the shoe without covering the toes or obstructing their movement. Consequently, the present device can remain perpetually installed onto, say, an athletic shoe without appreciably inhibiting any movements or sacrificing any comfort during non-dolly related wear. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a right perspective view of the shoe attachment device in accordance with the present disclosure; 
           [0015]      FIG. 2  is another perspective view of the same; and 
           [0016]      FIG. 3  is a right perspective view of the same, the device being shown attached to a show and engaging a dolly wheel axle. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0017]    Referring now to  FIGS. 1 and 2 , there is illustrated a preferred embodiment of the shoe attachment device  1  of the present invention. The present device  1  is attachable to a laced shoe  30 , as shown in  FIG. 3 , and it enables the user to hook and horizontally pull on the wheel axle  20  of a common hand truck with his or her leg. 
         [0018]    Generally speaking, when a load-carrying hand truck, or “dolly,” is sitting upright on the ground, the load that it is used to haul rests on the platform part (not shown) of the dolly while the platform is flush against the ground. Therefore, if the bottom surface area of the load is more expansive than is the surface area of the dolly platform, part of that load bottom surface will be separated from the ground only due the thickness of the dolly platform, and some of it may even be contacting the ground while the dolly is at rest. Of course, if not already contacting the ground, it can be easily put in contact with the ground by the dolly operator slightly tilting the dolly forward. In any event, a portion of the load bottom surface being in contact with the ground allows for friction between those surfaces to produce relative movement of the platform and the load when the dolly is pulled horizontally. More specifically, application of pulling force to the dolly may cause the dolly platform to travel horizontally while ground friction causes load item remain(s) to remain in place such that, eventually, the load is entirely resting upon the ground and the dolly platform is entirely removed from underneath it. The shoe attachment device  1  of the present invention facilitates that displacement. 
         [0019]    The shoe attachment device  1 , an example of which is shown in the accompanying drawings, comprises two main components: a metatarsal guard  2  and a lip  4 . In a preferred embodiment, the metatarsal guard  2  is a substantially convex shell formed by a flat or slightly arcuate central portion  12  that is laterally flanked by more downwardly curved left and right portions  14 ,  16 . In some embodiments, however, the metatarsal guard  2  may have a more uniformly arcuate structure with no distinctive left, right and center portions. Regardless, the guard  2  has a longitudinal width such that, when properly installed onto a laced shoe  30 , the guard  2  convers the front portion of the metatarsal region of the foot without extending into the phalangeal region, as may be gleaned from viewing  FIG. 3 . 
         [0020]    The forward end of at least the central portion  12  of the metatarsal guard  2  is met by a planar lip  4  which is vertically oriented to be roughly perpendicular to the plane of the guard central portion  12  (to the extent that any part of the central portion  12  is planar) and give the device  1  an overall L-shaped profile when viewed from its right or left side. Preferably, a rounded crease is formed at the junction of the guard  2  and lip  4  to strengthen the joint. It is also preferable that the guard  2  and lip  4  be fabricated of an elastic, but rigid, material. Some plastics and rubbers are suitable, but a plastic may be most preferable due to its lighter weight. 
         [0021]    To improve wearer comfort, adhered to the underside (i.e., the foot side surface) of the metatarsal guard  2  as well as the base of the lip  4  is resilient material, such as a resilient foam, in the form of either a single continuous cushion or distinct guard and lip cushions  6 ,  8 . Preferably, the lip cushion  8  (or portion of a unitary cushion that is positioned underneath the lip  4 ) is thicker than is the adjacent guard cushion  6  (or cushion portion positioned underneath the guard  2 ). That is because when a user properly positions the device  1  against a dolly axle  20  as shown in  FIG. 3 , pulling the foot horizontally so that the lip  4 , not the guard  2 , forcefully presses against the axle  20  causes the device  1  to press downward into the wearer&#39;s foot most pronouncedly at the base of the lip  4 . 
         [0022]    Finally, formed within each of the left and right portions  14 ,  16  of the metatarsal guard  2  is at least one hole  18  through which shoelaces are to be threaded in order to secure the attachment  1  to a shoe  30 , as can be seen in  FIG. 3   
         [0023]    Aspects of various embodiments of the present invention that are not recited above or claimed below may be noted from observing the illustrations included herein.