The present invention relates to footwear, and more particularly to safety footwear including metatarsal guards.
The human foot includes many bones that can be subject to crushing forces when impacted by falling or dropped items. For example, the foot includes multiple elongated metatarsal bones extending alongside one another in the instep region which extends forwardly from the front of the ankle to the base of the toes. These bones are particularly vulnerable to fracture when impacted by falling objects. In the United States, over 100,000 individuals are injured annually due to such accidents, some being severely incapacitated or maimed.
Many manufacturers produce footwear designed to prevent injuries to the metatarsals and instep region in general. Such footwear typically includes an external metatarsal guard. An external metatarsal guard usually includes a rigid, durable, synthetic plastic or metal shield placed over the exterior of the footwear to cover the instep region of the foot. Sometimes, the shield is concealed by a fabric or leather cover that matches the remainder of the footwear. The front edge of the external metatarsal guard usually is fastened via stitching, staples or other fasteners to a welt, outsole or periphery of the footwear around the toes. This can ensure consistent positioning of the shield over the metatarsal bones, and thus constant protection of those bones.
An issue with some external metatarsal guards, however, is that they can limit mobility, and can make the appearance of the footwear unsightly. Specifically, the rigid external shield can impair the range of motion of the foot during a natural walking or running gait. The rigid external shield also can pinch the instep when a wearer bends or squats. In cases of particularly large or poorly designed external shields, they can create a snagging or tripping hazard, perhaps causing injury.
In an effort to avoid the above issues with a conventional external metatarsal guard, some footwear manufacturers alternatively produce footwear with an internal metatarsal guard to compete against other footwear including the external metatarsal guard. An internal metatarsal guard usually is incorporated directly into the instep of the footwear, concealed by the fabric or leather of the footwear in the instep. The internal metatarsal guard can include a shield constructed from a semi rigid foam that is generally flexible but impact resistant. The internal metatarsal shield is generally completely concealed within the footwear. Because it is semi rigid, it can flex, providing the user with more mobility and flexion throughout the instep. While this is helpful, sometimes an internal metatarsal guard can offer slightly less protection than the external metatarsal guard rigid shield, which is a trade-off of flexibility for protection between the competing technologies.
Accordingly, there remains room for improvement in the field of metatarsal guards that protect the metatarsal bones and instep of a wearer's foot from forceful impacts, and simultaneously provides comfort, flexibility and reliability in an aesthetically pleasing package.
Footwear is provided including a hybrid metatarsal guard system having an external metatarsal guard and an internal metatarsal guard. The external metatarsal guard optionally can include first and second overlapping metatarsal guard plates that articulate relative to one another like a lobster tail, with one or both of the plates overlapping the internal metatarsal guard. The footwear and its components provide impact and crushing force resistance, yet the footwear is flexible enough to provide enhanced mobility to a wearer.
In one embodiment, the footwear includes an internal metatarsal guard plate constructed from an open cell, breathable foam. The internal metatarsal guard plate is located on the interior of the upper, and extends generally over the instep region and/or metatarsal bones of a wearer when the footwear is worn.
In another embodiment, the internal metatarsal guard plate is overlapped by one or both of first and second external metatarsal guard plates. The first metatarsal guard can overlap a first portion of the internal metatarsal guard and the second metatarsal guard can overlap a second portion of the internal metatarsal guard.
In still another embodiment, the first and second external metatarsal guard plates can be constructed from a rigid thermoplastic material. The plates can be generally concave, with the instep region of the upper projecting upwardly into a concave recess formed on undersides of the plates. One or both of the external metatarsal guard plates can include a front edge, an opposing rear edge, a medial edge and an opposing lateral edge. The medial and lateral edges can extend between the front edge and the rear edge. In both metatarsal guards, the front edge can be closer to the toe region than the respective opposing rear edge.
In even another embodiment, the front edges of the external metatarsal guards can be free from attachment to the upper. The front edge of the second external metatarsal guard also can be free from attachment to the exterior surface of the first external metatarsal guard. In use, the front edge of the second external metatarsal guard can slide or move over an exterior surface of the first external metatarsal guard.
In yet another embodiment, the first and second metatarsal guards can be joined with the upper substantially only via shoe laces that close the upper in normal use. For example, the rear edge of the first external metatarsal guard can be joined via a shoe lace to the upper. At least one of the rear edge, a medial edge and a lateral edge of the second external metatarsal guard can be joined via the same shoe lace to the upper,
In a further embodiment, the second external metatarsal guard can include an upwardly extending wall near the front edge of that guard. The wall can transition to a keeper plate. The wall and the keeper plate collectively can define a keeper recess that is formed on an underside of the second external metatarsal guard. Optionally, a portion of the first external metatarsal guard, for example, the first rear edge, can be disposed in the keeper recess when the footwear is in a flat mode.
In still a further embodiment, one or both of the external metatarsal guards can define a plurality of grooves that enhance the flexibility of the guards when the foot flexes during a gait cycle of the wearer. The grooves can be defined on the front surfaces of the guards only, so that flexion is enhanced forwardly, while deflection capability of the guard generally is uncompromised.
The footwear of the current embodiments provides a metatarsal guard assembly having exceptional impact absorption and clearance above the wearer's foot after impact by an object. In turn, this can provide enhanced protection to the metatarsal bones and instep region of the wearer's foot. In addition, the metatarsal guard assembly, with its overlapping, articulating parts, is exceptionally flexible, allowing the foot to follow a more natural range of motion during a gait cycle of the wearer.
These and other objects, advantages, and features of the invention will be more fully understood and appreciated by reference to the description of the current embodiment and the drawings.
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited to the details of operation or to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention may be implemented in various other embodiments and of being practiced or being carried out in alternative ways not expressly disclosed herein. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. Further, enumeration may be used in the description of various embodiments. Unless otherwise expressly stated, the use of enumeration should not be construed as limiting the invention to any specific order or number of components. Nor should the use of enumeration be construed as excluding from the scope of the invention any additional steps or components that might be combined with or into the enumerated steps or components.
An article of footwear in accordance with the current embodiment is shown in
A portion of this metatarsal guard assembly is disposed on the exterior 11 of the footwear 10, while another portion is disposed on the interior 21 of the upper 20 as shown in
Optionally, the metatarsal guard system 40 can also include a second external metatarsal guard plate 42. This plate 42 can overlap at least a portion of the first external metatarsal guard plate 41, and can be on the exterior 11 of the footwear 10. The second metatarsal guard plate 42 can move with a lobster tail like articulation relative to the first metatarsal guard. For example, in a lobster tail articulation, a free front edge 42FE of the second external metatarsal guard can slide and move freely over the upper surface or exterior surface 41U of the first external metatarsal guard 41. The front edge 41FE of the first external metatarsal guard 41 also can be free relative to the upper 20 and its exterior surface. Thus, both front edges of both plates can be free to move and slide over the exterior surface of the upper or the exterior surface of the first external metatarsal guard. This type of movement mimics the different sections of a lobster tail during movement so that no region of the upper is exposed through the respective first and second external metatarsal guards. This provides enhanced, consistent protection to the underlying upper and instep region 13 of the footwear, which in turn provides protection to the underlying metatarsal bones MB in that instep region 13.
Although the current embodiments are illustrated in the context of a working boot or safety shoe, they may be incorporated into any type or style of footwear, including performance shoes, hiking shoes, trail shoes and boots, hiking boots, all-terrain shoes, barefoot running shoes, athletic shoes, running shoes, sneakers, conventional tennis shoes, walking shoes, multisport footwear, casual shoes, dress shoes or any other type of footwear or footwear components. It also should be noted that directional terms, such as “vertical,” “horizontal,” “top,” “bottom,” “upper,” “lower,” “inner,” “inwardly,” “outer” and “outwardly,” are used to assist in describing the invention based on the orientation of the embodiments shown in the illustrations. Further, the terms “medial,” “lateral” and “longitudinal” are used in the manner commonly used in connection with footwear. For example, when used in referring to a side of the shoe, the term “medial” refers to the inward side (that is, the side facing the other shoe) and “lateral” refers to the outward side. When used in referring to a direction, the term “longitudinal direction” refers to a direction generally extending along the length of the shoe between toe and heel, and the term “lateral direction” refers to a direction generally extending across the width of the shoe between the medial and lateral sides of the shoe. The use of directional terms should not be interpreted to limit the invention to any specific orientation.
Further, as used herein, the term “arch region” (or arch or midfoot) refers generally to the portion of the footwear or sole assembly corresponding to the arch or midfoot of the wearer's foot; the term “forefoot region” (or forefoot) refers generally to the portion of the footwear forward of the arch region corresponding to the forefoot (for example, including the ball and the toes) of a wearer's foot; and the term “heel region” (or heel) refers generally to that portion of the footwear rearward of the arch region corresponding to the heel of the wearer's foot. The forefoot 17, arch or midfoot 18 and heel 19 region are generally identified in
As shown in
For purposes of disclosure, the embodiments herein are described in connection with footwear in the form of a work boot 10 having an upper 20, which as mentioned above, optionally can include a Strobel construction. The upper 20 is joined with the outsole 30. The joining of the outsole 30 and the upper 20 can be accomplished using adhesives, cement, injection molding, pour molding or any other technique used to join an upper and outsole. As illustrated, the insole board or liner 22 can rest or be placed immediately adjacent the outsole 30.
Optionally, the footwear 10 can include a welted construction in which a welt 32 is used to join the upper 20 to the outsole 30. If desired, a stitch 32S can extend through the welt 32 as well as the outsole 30. Of course, other constructions can be used to attach the outsole 30 to the upper 20.
The outsole 30 can be disposed below the upper 20 and any optional midsole included in the construction. The outsole 30 can be constructed from one or more materials. The current embodiment can be constructed from rubber and can include lugs, tread, or other gripping elements. Alternatively, it can be constructed from a thermoplastic polyurethane elastomer (TPU), nylon or other polymer blend that includes nylon and/or TPU. Of course, the outsole can be constructed from any relatively wear resistant polymer, elastomer and/or natural or synthetic rubber or other materials capable of providing the desired functional characteristics. Other materials such as fiber-reinforced polymers can be used. These can include epoxy, polyethylene, polyester, thermosetting plastic reinforced with carbon, glass and/or aramid fibers.
As illustrated in
In addition, the footwear 10 optionally can be constructed to include a rigid protective toe element 50. This element can be a steel toe, but of course can be constructed from other materials. For example, it can be constructed from rigid polymeric materials of sufficient thickness to deflect forces and/or loads from objects dropped on the toe. The rigid toe protective element 50 can be configured to extend throughout the toe region 14 of the wearer's foot generally extending rearwardly toward the heel region 19 of the foot, but located substantially within the forefoot region 17 (
The upper 20 can include an upper material 24 which can be any conventional upper material, such as leather, mesh, fabric, plastic, rubber or other materials. The upper 20 extends to and can be joined with the exterior surface of the protective toe element 50. The material 24 can extend upwardly toward the tongue 26 of the footwear. The tongue 26 can be constructed from a similar material but can include padding such as a flexible closed cell foam disposed therein. As illustrated, the uppermost portion of the material 24 is stitched with stitching 26S to the tongue 26. The tongue 26 can cover a tongue opening 260 defined in the upper portion of the upper 20.
In the construction as shown in
The construction of the internal metatarsal guard can be such that it still provides for enhanced flexibility and mobility to a wearer when the footwear moves from the static or flat mode shown in
Generally, the internal metatarsal guard 51 is separated from and does not contact or come into or directly engage the external metatarsal guards, for example the first external metatarsal guard 41 or the second external metatarsal guard 42. The internal and external metatarsal guards can be separated from the internal metatarsal guard via the upper material 24 and/or the tongue 26. In use, only the internal metatarsal guard 51 comes in contact with or engages the instep of the wearer's foot. The internal metatarsal guard usually can be configured so that it prevents the external metatarsal guards from contacting the foot or otherwise engaging the instep of the wearer's foot.
The internal metatarsal guard 51 can be of a saddle-type shape and configuration. For example, it is concave in extending from the toe region 14 toward the heel region, for example, as shown in
As shown in
As shown in
Returning to
The rear edge 41RE and/or portions of the side edges 41LE and/or 41ME can define lace holes 41LH, which are sized and oriented to accept shoelaces 29 from the footwear to which the first external metatarsal guard is attached. The lace holes can be disposed on opposite sides of the first external metatarsal guard 41, generally near the side edges 41LE and 41ME. Of course, in other constructions, these lace holes 41LH can be located closer to the center line CL of the boot or footwear 10 as desired. The lace holes 41LH can be sized to accept the shoelaces 29 therethrough. The lace holes can be of a rounded, circular or elliptical shape so as to cleanly receive the shoelaces, and to enable the shoelaces 29 to slide therethrough when being installed. Optionally, the lace hole 41LH of the first external metatarsal guard plate 41 can be perfectly aligned with underlying eyelets defined by the upper, adjacent the tongue opening 260. In this construction, the lace 29 can extend straight through the lace hole 41LH and directly into an underlying eyelet of the boot. In some cases, the eyelets can be constructed from metal, plastic or other rigid materials, or simply cut in the material from the upper is constructed. Further optionally, the lace holes 41LH can be defined through the body of the first plate 41. For example, the lace holes can extend generally from the upper surface 41U to the rear or back surface 41B of the body of the plate 41 itself—rather than being in the form of some secondary component extending from or attached to the plate 41.
As shown in
Optionally, the first metatarsal guard plate 41 can have several thicknesses. For example, near the lateral edge 41LE and the medial edge 41ME, the thickness can be less than the thickness along the center line CL of the footwear (other than where the grooves 41G are defined). In general, the thickness over the top of the footwear generally along the center line CL can be the greatest. This is so that when an object impacts the instep region 13, the plate 41 can provide enhanced protection to the metatarsal bones lying there beneath.
The front edge 41FE of the first metatarsal guard plate 41 is free from attachment to the upper or any other component of the footwear beyond the first metatarsal plate 41. The rear edge 41RE however, is attached to the upper and/or generally to some other footwear component. In this manner, the rear edge 41RE remains attached, while the front edge 41FE is allowed to slide over or relative to the upper or exterior surface of the upper in the instep region and/or the toe region. With this added mobility and movement of the first plate, it can enable the metatarsal guard to move quite easily during the natural gait cycle of a wearer. This in turn, can enhance the perceived flexibility of the footwear—even with the added protection over the instep via the metatarsal guard assembly 40. The first external metatarsal guard plate 41 includes an exterior or upper surface 41U as shown in
As shown in
The first external metatarsal guard plate 41 can be constructed from a variety of materials. These materials can be substantially rigid and generally inflexible except under significant force. For example, the plates can be constructed from a thermoplastic material. Some examples include, but are not limited to, polypropylene, polyethylene, nylon, ABS, polycarbonate, polystyrene, polyvinylchloride, Teflon or other polymeric materials. If desired, the plates alternatively can be constructed from metals, composites, glass or fiber reinforced materials and the like. Further, the separately constructed first and second plates can be formed from entirely different materials in some applications. Generally, in most applications, both plates can be constructed from the same material for ease of manufacture and assembly.
As mentioned above, the metatarsal guard assembly 40 includes a second external metatarsal guard plate 42. This second external metatarsal guard plate 42 can be constructed from materials such as those enumerated above in connection with the first external metatarsal guard plate 41. The second external metatarsal guard plate 42 can include a front edge 42FE and a rear edge 42RE. The front edge 42FE is closer to the toe region 14 than the rear edge 42RE. The front edge 42RE can be generally rounded or arcuate in shape. Of course, it can optionally be slightly angled if desired. Further, the front edge, as shown in
The second external metatarsal guard plate 42 also can include a lateral edge 42LE and a medial edge 42ME that are generally opposed, across opposite sides of a center line CL of the footwear. These side edges 42ME and 42LE can generally merge into the front edge 42FE and rear edge 42RE respectively.
The side edges 42ME and 42LE can define a plurality of lace holes 42LH. These lace holes can be located along the outermost perimeters of the second plate 42. Optionally, the uppermost lace holes 42LHU can be defined at least partially in or at least near the rear edge 42RE of the second metatarsal plate 42. The front edge 42FE of the second metatarsal guard plate 42 is free from attachment to the upper or any other component of the footwear beyond the second metatarsal plate 42. The rear edge 42RE however, is attached to the upper and/or generally to some other footwear component. In this manner, the rear edge 42RE remains attached, while the front edge 42FE is allowed to slide over or relative to the upper or exterior surface of the upper in the instep region and/or the toe region. With this added mobility and movement of the second plate, it can enable the metatarsal guard to move quite easily during the natural gait cycle of a wearer. This in turn, can enhance the perceived flexibility of the footwear—even with the added protection over the instep via the metatarsal guard assembly 40.
Optionally, the second external metatarsal guard plate 42 can define a keeper recess 42KR as shown in broken lines in
Optionally, the second external metatarsal guard plate 42 is of a substantially uniform thickness from the front edge 42FE to the rear edge 42RE. In some embodiments, the thicknesses can be optionally 0.5 mm to 3 mm, further optionally 1 mm to 2 mm. Of course, other thicknesses can be utilized as depending on the particular application. Further optionally, there can be grooves 42G formed in the upper surface 42U of the second plate 42. The upper surface 42U is opposite a lower or rear surface 42R. This rear surface 42R, particularly along the front edge 42FE is configured to engage and slide along or relative to the upper surface 41U of the first plate 41.
The keeper recess 42KR can be formed by an upwardly extending wall 42W that extends from a main body portion 42MB of the second plate 42. This upwardly extending wall 42W can extend at an angle or generally can be curved or rounded upwardly, away from the main body 42MB. This upwardly extending wall 42W can transition to a keeper plate 42KP that extends outwardly and forwardly to the front edge 42FE of the second plate. Adjacent the upstanding wall 42W, a laterally extending groove 42GW can be defined by the plate. This groove 42GW can enable the keeper plate to flex slightly upwardly upon or during a wearer's natural gait to provide enhanced flexibility to the second plate and generally to the metatarsal guard assembly 40. Optionally, the thickness throughout the main body 42MB, the upstanding wall 42W and the keeper plate 42KP can be substantially consistent.
Operation of the footwear 10 and the metatarsal guard assembly 40 in general will now be described. In general, the footwear 10 is worn by a wearer, optionally to provide added safety and protection to the metatarsal bones MB of the wearer's foot in the instep region 13 as shown in
As shown in
As shown in
The second plate 42 also can dynamically move. For example, while the side edges 42LE and 42 ME remain attached via shoe laces to the upper, the front edge 42FE, which is free from attachment to the upper and the first plate 41 slides forwardly a distance D2 relative to the upper exterior surface of the first external metatarsal guard 41, generally toward the toe region 14 of the footwear. This sliding movement of the second plate relative to the first plate generally mimics movement of individual plates, for example, in a lobster tail. This type of movement herein is referred to as a lobster tail articulation. Those first and second external metatarsal guards thus move relative to one another via a lobster tail articulation. This in turn promotes flexibility to the instep region of the footwear so that the footwear can actually bend somewhat unimpeded by the metatarsal guard assembly 40. This can provide added mobility and flexibility to the wearer's foot, even while the wearer's foot is protected via the metatarsal guard assembly 40. In addition, the front edge 41FE slides relative to the outer surface or exterior of the upper. This acts somewhat like a lobster tail as well, however, the upper 41 itself does not slide relative to any other components.
In addition, in the flexing mode, the rear edge 42RE can optionally exit the keeper recess 42KR, and/or can disengage the undersurface of the keeper plate 42KP. When this occurs, the rear edge 41RE can sometimes disengage the undersurface of the keeper plate 42KP and can ride rearward, past the wall 42W. The front edge 42FE, however, can maintain contact with the upper surface 41U of the first plate 41. Further, the upper surface 41U can ride or slide within the front recess 42P along the front edge 42FE when included. Again, with this movement of the different metatarsal guard plates 41 and 42, the footwear is provided with enhanced flexibility and mobility.
Even with the enhanced flexibility and mobility, the superguard provides exceptional protection to the instep. For example, the footwear of the embodiments herein has been tested according to standardized test ASTM F2412-11:7.5. This test is designed specifically to test metatarsal guards and footwear for impact absorption and clearance after impact. Generally, the clearance C is measured as shown in
Surprisingly and unexpectedly, the metatarsal guard system herein has exhibited a range of clearance under the ASTM test of optionally at least 1.50 inches above a wearer's foot; further optionally, at least 1.52 inches above a wearer's foot, and even further optionally at least 1.63 inches above a wearer's foot. It was discovered that the external metatarsal guard and internal metatarsal guard acted synergistically with one another to enhance the overall protection and clearance provided under the aforementioned ASTM test. Indeed, the tested footwear exhibited an improvement of at least 150%, at least 152%, or at least 163% over the standard of the ASTM test. Thus, with the metatarsal guard assembly herein, the footwear provides substantial protection to the wearer without sacrificing comfort and flexibility.
A first alternative embodiment of the footwear is illustrated in
Directional terms, such as “vertical,” “horizontal,” “top,” “bottom,” “upper,” “lower,” “inner,” “inwardly,” “outer” and “outwardly,” are used to assist in describing the invention based on the orientation of the embodiments shown in the illustrations. The use of directional terms should not be interpreted to limit the invention to any specific orientation(s).
The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. For example, and without limitation, any individual element(s) of the described invention may be replaced by alternative elements that provide substantially similar functionality or otherwise provide adequate operation. This includes, for example, presently known alternative elements, such as those that might be currently known to one skilled in the art, and alternative elements that may be developed in the future, such as those that one skilled in the art might, upon development, recognize as an alternative. Further, the disclosed embodiments include a plurality of features that are described in concert and that might cooperatively provide a collection of benefits. The present invention is not limited to only those embodiments that include all of these features or that provide all of the stated benefits, except to the extent otherwise expressly set forth in the issued claims. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular. Any reference to claim elements as “at least one of X, Y and Z” is meant to include any one of X, Y or Z individually, and any combination of X, Y and Z, for example, X, Y, Z; X, Y; X, Z; and Y, Z.
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Number | Date | Country | |
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20160331072 A1 | Nov 2016 | US |
Number | Date | Country | |
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62159707 | May 2015 | US |