Patent Publication Number: US-RE43214-E

Title: Metatarsal protector

Description:
More than one reissue application has been filed for the reissue of patent application Ser. No. 09/686,546, filed Nov. 11, 2000, now U.S. Pat. No. 6,618,962. The reissue applications are U.S. application Ser. No. 11/029,250, filed Jan. 4, 2005, now U.S. Pat. No. Re. 40,757, and the present application, which is a continuation reissue of the U.S. patent application Ser. No. 11/029,250. 
    
    
     TECHNICAL FIELD 
     This invention relates to footwear, and more particularly to safety footwear. 
     BACKGROUND 
     In harsh and dangerous environments (e.g., construction and lumber operations), workers often wear heavy-duty work shoes or work boots to protect their feet from injury as well to provide comfort and support. Indeed, the Occupational Safety and Health Administration has set forth regulations for the types of work boots and work shoes to be used by workers in certain occupations including construction and mining. 
     Work boots and work shoes used in such environments typically have soles and uppers fabricated of heavier and durable materials. In certain environments, additional protective features may be constructed within the work boot or work shoe. For example, where there is a risk of heavy articles being dropped on the wearer&#39;s foot, steel toes, metatarsal guards, and puncture-proof covers are typically incorporated into or over the upper. Similarly, in high voltage environments, thicker and higher dielectric materials are used in fabrication of the soles of the work boots and work shoes. 
     SUMMARY 
     In a general aspect of the invention, an instep guard for use in footwear to protect the metatarsal region of the a foot includes an elastic support having hollow passages, and a shape and size commensurate with the instep section of the footwear. 
     In another general aspect of the invention, footwear for protecting a foot includes an upper defining an opening for receiving a wearer&#39;s foot and an outsole attached to the upper, the upper further including an instep guard positioned at an instep portion and having the features described above. 
     Embodiments of the invention may include one or more of the following features. The instep guard includes a sheet and a plurality of support members extending from the sheet to define the hollow passages, which are filled with air. The elastic sheet and the support members define at least some of the hollow passages. The hollow passages are elongated and at least one of the passages has a cross-section that is circular, ovoid, or triangular in shape. The support members may define two different types of hollow passages, one of which has a cross section of a first shape and the other of which has a second cross section shape. The instep guard further includes a second sheet attached to the first sheet by the support members. The instep guard may be formed of a flexible, resilient material such as rubber. 
     The instep guard is positioned on an underside of the instep portion of the footwear. For example, a liner is positioned beneath the instep portion of the footwear and the instep guard is then positioned on the underside of the instep portion by sewing the liner to the instep portion around the instep guard. The footwear further includes a steel toe positioned on a toe portion of the upper, and the instep guard is attached to the toe portion. 
     Among other advantages, the instep guard protects the metatarsal region of the foot from blows or forces that could, otherwise, injure the foot. The elastic nature of the instep guard and the air-filled channels make the footwear comfortable to the wearer. The instep guard provides sufficient protection against impacts that a wearer may be subjected to in a harsh environment. 
     The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of protective footwear having an instep guard positioned in an instep portion of the footwear: 
         FIG. 2  is a vertical cross-section of the footwear of  FIG. 1 ; 
         FIG. 3  is a perspective view of the instep guard of  FIG. 1 ; 
         FIG. 4  is a cross-section view of the instep guard of  FIG. 3 ; 
         FIGS. 5A-5C  are cross-sectional views of alternative embodiments of the instep guard of  FIG. 3 . 
     
    
    
     Like reference symbols in the various drawings indicate like elements. 
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a shoe  12  for protecting a foot includes an upper  13  having a quarter  16  and a vamp  18  attached together with stitching  20 . Vamp  18  and quarter  16  may be constructed from a durable material, such as leather. An outsole  14  is attached to the upper  13  using conventional lasting techniques. Vamp  18  covers a front part of the foot, while quarter  16  covers a rear part of the foot. Vamp  18  has eyelets  22  for receiving conventional front lacing (not shown) and a tongue  24  for protecting the foot from the front lacing. Quarter  16  and vamp  18  together define an opening  27  of the upper  13  for receiving the foot. 
     Vamp  18  has an instep portion  26  that covers the metatarsal region of the wearer&#39;s foot when the shoe is worn. As will be described below in greater detail, shoe  12  includes an instep guard  40  ( FIG. 2 ) that is positioned with the instep portion  26  to protect the metatarsal section of the foot, for example, from inadvertent blows or forces. 
     Referring to  FIG. 2 , shoe  12  also includes instep guard  40 , a lining  30 , and a steel toe  32 . Steel toe  32 , which protects the wearer&#39;s toe region, is attached to a toe portion  34  of an underside  36  of the vamp  18 , for example, using glue. Tape  38  adheres the instep guard  40  to the steel toe  32 , thereby positioning the instep guard  40  on instep portion  26  of the underside  36  of the vamp  18 . The instep guard  40  is further held in place by stitching  42  surrounding instep guard  40 , which attaches lining  30  to the underside  36  of the vamp  18 . In this manner, instep guard  40  is sandwiched between the lining  30  and the vamp  18  and maintained in position along the underside  36  of the vamp  18  to protect the metatarsal region of the foot from inadvertent blows or forces. 
     Referring to  FIG. 3 , the instep guard  40  is a generally planar member that is large enough to cover and protect the instep portion  26  of the shoe  12 . The instep guard  40  is formed from an elastic material, such as rubber or a suitable synthetic material, which is sufficiently compliant to provide comfort to the foot but is elastic enough to provide protection to the metatarsals of the foot. In certain instances, the instep guard may be shaped to only cover the instep portion  26  of the shoe  12 , as shown in  FIG. 3 , to make the shoe  12  more comfortable. In these instances, the instep guard  40  may have an ovoid shape and may be elongated along an axis  43  of the foot to match the shape of the instep portion  26  of the shoe. The thickness of the guard is chosen to provide the necessary protection without making the shoe uncomfortable. For example, the guard may be a quarter of an inch thick, 4 inches long and 3 inches wide. The elastic material of the guard has channels running through it to provide better comfort and protection as described below with references to  FIG. 4 . 
     Referring to  FIG. 4 , instep guard  40  is formed to include hollow channels  56 ,  58  that absorb shock to the feet without sacrificing comfort. In particular, instep guard  40  includes a first planar sheet  50  and a second planar sheet  52 , with curved support members  54  extending between the planar sheets  50 ,  52  to define elongated hollow channels  56  with circular cross-sections. The channels extend through the instep guard  40 , for example, along the axis  43  of the foot. Cross pieces  55  join convex surfaces of adjacent curved members. Each cross piece  55 , defines an elongated hollow channels  58  with each planar sheet  50 ,  52  and the corresponding curved members  54 . The hollow channels  58  each have a substantially trapezoidal cross-section. Thus the instep guard  40  defines parallel air-filled channels aligned along the axis  43  of the foot to provide protection from inadvertent blows or forces to the metatarsals of the foot without making the shoe uncomfortable. 
     Referring to  FIG. 5A , a first alternative embodiment of the instep guard  60  has a single planar sheet  62  with curved support members  64  extending form the planar sheet  62  to define circular air-filled channels  66 . Concave surfaces  68  of the support members  64  are joined by cross pieces  70  to define air-filled channels  72  with substantially trapezoidal cross-sections. 
     Referring to  FIG. 5B , a second alternative embodiment of the instep guard  80  that has a single planar sheet  82 . Planar support members  84  extend from the planar sheet  82  at an angle  85  (such as 60°) to define elongated channels  86  with triangular cross-sections. 
     Referring to  FIG. 5C , a third alternative embodiment of the instep guard  90  includes an undulating sheet  92  defining furrows  94 . Curved support members  96  extend from the furrows  94  to define elongated channels  98 , which have ovoid cross-sections. In all three alternate embodiments, it is preferable to have a second sheet  100  connected to the first sheet  62 ,  82 ,  92  by the support members  64 ,  84 ,  96 . However, the second sheet may be omitted in certain applications. 
     A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, the air-filled channels may have any shape or configuration so long as they provide the necessary protection to metatarsals. For example, they need not be parallel or elongated. Similarly, the instep guard does not have the same shape as the instep portion of the shoe  12 . For example, it could be larger than the instep portion so long as it provides protection to the instep portion. The instep guard may be used with a shoe that does not include a steel toe. 
     Accordingly, other embodiments are within the scope of the following claims.