Abstract:
An energy absorptive impalement protection system is utilized in preventing impalement and minimizing injuries due to impact with the end of a concrete reinforcing bar or other similar type of bar. The energy absorptive impalement protection system is comprised of a protective cover apparatus that has a simplified construction comprised of a base that is removably attached to an end of a reinforcing rod, a metal band on the base that surrounds the rod end and reinforces the base against side-to-side movement relative to the rod in response to an impact force, a metal impact plate on the base that absorbs and distributes the force of impact, and a resilient, compressible and stretchable cover on the base that together with the base encloses the band and cover in the apparatus and also absorbs some of the force of impact.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This patent application claims the benefit of provisional patent application Ser. No. 61/056,039, filed on May 26, 2008. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention pertains to an energy absorptive impalement protection system that is utilized in preventing impalement and minimizing injuries due to impact with the end of a concrete reinforcing bar or other similar type of bar. The energy absorptive impalement protection system is comprised of a protective cover apparatus that is designed to meet and surpass Occupational Safety and Health Administration (OSHA) standards for construction worksites. 
         [0004]    The protective cover apparatus has a simplified construction that is comprised of a base that is removably attached to an end of a reinforcing bar, a metal band on the base that surrounds the bar end and reinforces the base against side-to-side movement relative to the bar in response to an impact force, a metal impact plate on the base that absorbs and distributes the force of impact, and a resilient, compressible and stretchable cap on the base that together with the base encloses the band and impact plate in the apparatus and also absorbs some of the force of impact. Should a person fall on a bar end covered by the protective cover apparatus of the invention, the apparatus absorbs the initial kinetic energy of the impact while distributing the point of impact over a greater surface area to prevent impalement and minimize injuries. 
         [0005]    2. Related Prior Art 
         [0006]    Prior art concrete reinforcement bar (rebar) protective covers prevent impalement of a person falling onto an end of a bar by distributing the force of impact over a greater surface area than the surface area of the bar end. This basic functioning of prior art rebar protective covers is required by OSHA standards. However, prior art rebar protective covers do not address the issue of absorbing the energy of impact. They are basically designed to distribute the force of impact over a greater area. Therefore, the kinetic energy of a human body impacting with a rebar protective cover is absorbed by the compression and deformation of the portion of the human body that impacts with the cover. While prior art rebar protective covers may prevent impalement of the portion of the human body impacting the cover, prior art covers still present a high risk for serious injuries, both internal and external, due to the force of impact. 
       SUMMARY OF THE INVENTION 
       [0007]    The energy absorptive impalement protection system of the present invention is designed to overcome the above-described shortcoming of prior art rebar protective covers. In addition, the protective cover apparatus of the invention has a simplified construction that is comprised of four basic component parts that reduces the manufacturing costs of the apparatus. The four basic component parts of the apparatus include a base, a restraining band, an impact member or plate, and a cap. 
         [0008]    The base is designed to align with and be removably attached to the projecting end of a reinforcing bar, and to hold the restraining band, impact member, and cap in place relative to the bar end. The base has a tubular length with opposite first and second ends. The first end of the base has an interior bore containing aligning fins that are designed to be removably attachable over the projecting end of the reinforcing bar. As the base extends from its first end toward the second end, the configuration of the base widens. At the base second end, the base is designed to hold the restraining band in position around the base interior bore, to hold the impact plate adjacent the restraining band and over the end of the base interior bore, and to hold the cap over the impact plate. The second end of the base may be square, rectangular, oval, hexagonal, or any other shape. The preferred embodiment is circular. The second end of the base is of a size that provides for an overall apparatus top surface area or impact surface area of at least 16 square inches. In the preferred embodiment, the base is constructed of a plastic material which allows for some movement of the base upon impact while also providing a resistance to the movement and support to the apparatus. 
         [0009]    The band in the preferred embodiment is constructed as a metal cylinder. It is assembled into an annular groove in the base second end. This positions the band around the base interior bore and around the end of the rebar to which the base is attached. This positioning of the band on the base provides additional resistance to the side-to-side movement of the base relative to the rebar end in response to a force impacting with the apparatus that is not axially aligned with the rebar end. 
         [0010]    The impact member or impact plate is centered above the interior bore of the base, the band surrounding the interior bore, and the bar end inserted into the interior bore. The primary functions of the impact member are to provide a rigid surface opposing the end of the rebar inserted into the apparatus, to deform and absorb some of the force of impact, and to provide a greater surface area to support the cap and receive the force of impact. In the preferred embodiment, the impact member is a circular cup-shaped plate of metal. 
         [0011]    The cap is positioned on the opposite side of the impact member from the base and is secured to a perimeter of the base. The connection of the cap with the base completely encloses the restraining band and the impact member within the apparatus. In the preferred embodiment, the cap is constructed of a resilient, compressible and stretchable material that absorbs some of the force of impact with the apparatus and provides a compressible area between the rigid surface of the impact member and the object impacting the apparatus. The cap also functions to distribute the force of impact over the 16 square inches of the base second end. In the preferred embodiment, the cap is constructed of rubber. 
         [0012]    Upon an object or person impacting with the protective cover apparatus of the invention, the cap and the cup-shaped configuration of the impact member are initially compressed, absorbing a portion of the kinetic energy of impact. As a result of the compression, the area of the cap begins to expand and the impact plate is deformed from the cup-shaped configuration toward a more planar configuration, thereby providing a greater surface area over which the force of impact is distributed. In this manner, the protective cover apparatus of the invention achieves the desired objectives of absorbing some of the kinetic energy of a human body impacting the apparatus and reducing the potential for serious injury to the body due to the impact. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Further features of the apparatus of the invention are set forth in the following detailed description of the preferred embodiment of the apparatus and in the drawing figures. 
           [0014]      FIG. 1  is a top perspective elevation view of the apparatus of the invention. 
           [0015]      FIG. 2  is a bottom plan view of the apparatus. 
           [0016]      FIG. 3  is a top plan view of the apparatus. 
           [0017]      FIG. 4  is a sectioned side elevation view of the apparatus. 
           [0018]      FIG. 5  is a sectioned, bottom perspective view of the component parts of the apparatus shown disassembled. 
           [0019]      FIG. 6  is a sectioned side elevation view of the component parts of the apparatus shown disassembled. 
           [0020]      FIG. 7  is a bottom perspective elevation view of the component parts of the apparatus shown disassembled. 
           [0021]      FIG. 8  is a top perspective elevation view of the component parts of the apparatus shown disassembled. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0022]    The energy absorptive impalement protective cover apparatus  12  of the present invention is shown in  FIG. 1 . The protective cover apparatus is primarily intended to function as an impalement protection system employed on the exposed ends of concrete reinforcement bars at construction sites. However, this is only one illustrative example of the use of the protective cover apparatus of the invention. The protective cover may be used as an impalement protection system on the exposed end of most any rod to absorb impact energy from an object impacting with the end of the rod. Other examples of possible uses of the protective cover include on a tent stake or canopy stake protruding from the ground, as a protective cover on a surveyor&#39;s stake protruding from the ground, as a protective cover on a concrete form stake, and as a protective cover on the end of any protruding stake or rod that could potentially come into contact with a person or object causing injury to the person or damage to the object. For example, the apparatus could be employed as a protective cover on the end of a stake or rod that could potentially contact a person walking past the stake or rod and scratching the person, or that could potentially contact an object such as an automobile passing by the stake or rod and scratching the automobile. 
         [0023]    The protective cover apparatus  12  of the invention has a simplified construction that comprises only four separate component parts. The four basic component parts of the apparatus  12  include a base  14 , a restraining band  16 , an impact member  18 , and a cap  22 . This simplified construction reduces the manufacturing costs of the apparatus. Although the apparatus of the invention has a simplified construction and only four component parts, the construction of the apparatus meets all requirements of the Occupational Safety and Health Administration (OSHA). 
         [0024]    In the preferred embodiment of the apparatus  12 , the base  14  is constructed of a plastic material typically employed in the construction of known impalement protective covers employed on the exposed ends of concrete reinforcement bars (rebar). Other similar types of materials may also be used for the base. As shown in the drawing figures, the base  14  has a general tubular configuration with opposite first  24  and second  26  ends. The base first end  24  is circular, and the base has a cylindrical configuration extending from the first end  24  toward the second end  26 . 
         [0025]    A hollow, cylindrical interior bore  28  extends into the base  14  from the base first end  24 . A first portion of the bore  28  is surrounded by a cylindrical interior surface  32 . The interior diameter of the cylindrical interior surface  32  is constant. As the interior bore extends toward the base second end, a second portion of the bore is formed with a necked-down portion having an interior surface  34  that has a smaller interior diameter dimension than the first portion of the bore. In the preferred embodiment, the interior diameter of the bore necked-down portion  34  is dimensioned to be just slightly larger than the diameter dimension of the end of a rod on which the apparatus is intended to be used. The cylindrical interior surfaces  32 ,  34  of the two portions of the interior bore  28  have a common center axis  36  that defines mutually perpendicular axial and radial directions relative to the apparatus  12 . 
         [0026]    As shown in the drawing figures, the base interior bore  28  extends axially through the base  14  from the base first end  24  and terminates at a circular end wall or end surface  38  of the bore  28 . The end surface  38  completely covers over the distal end of the base interior bore  28 . 
         [0027]    The base  14  is also provided with a plurality of flexible fins  42  that extend axially along the interior surface  32  of the first portion of the interior bore  28 . The fins  42  are similar in construction and function to fins employed in prior art rebar protective covers. However, it should be noted that the fins  42  of the base  14  are connected to only the interior surface  32  of the base bore  28  having the larger interior diameter. The fins  42  have projecting portions  44  that extend axially into the portion of the base bore  28  that is surrounded by the interior surface  34  having the smaller interior diameter. These fin projections  44 , although extending into the portion of the bore surrounded by the smaller diameter interior surface  34 , are not connected to the interior surface  34 . This provides the fin projections  44  with greater flexibility than the remaining portions of the fins  42  connected to the large diameter interior surface  32 . This greater flexibility of the fin projections  42  facilitates the removable attachment of the base  14  on the end of a rod with which the apparatus is used. 
         [0028]    As the base  14  extends from the first end  24  toward the second end  26 , the configuration of the base transforms from the cylindrical configuration adjacent the base first end  24  to a disk or cup-shaped configuration at the base second end  26 . The cup-shaped configuration of the base second end  26  is surrounded by a circular rim  46  that extends completely around the outer perimeter of the base  14 . Inside the rim  46  the base second end  26  is defined by a cup-shaped or concave second end surface  48 . As shown in the drawing figures, the second end surface  48  is not a continuously curved concave or cup-shaped surface, but instead is defined by a plurality of concentric surface areas that together give the base second end surface  48  a generally concave shape. The surface areas include a substantially flat and circular central area  52  that is opposite the interior bore end surface  38 , a first tapered annular portion  54  of the surface that surrounds the central area  52 , a second substantially flat annular portion  56  of the surface that surrounds the first tapered portion  54 , and a third annular tapered portion  58  of the surface that surrounds the second annular portion  56  and extends radially outwardly to the base rim  46 . It should be understood that in alternate embodiments, the base second end surface  48  could have a continuously curved, concave configuration, could have a truncated cone configuration, could have a conical configuration, or could have other equivalent configurations to those described and shown in the drawing figures. 
         [0029]    An annular groove  62  is recessed into the base second end surface  48 . The groove  62  surrounds the central portion  52  of the end surface  48 . The groove  62  has a cylindrical configuration and extends axially into the material of the base  14  at a position that is spaced radially outward from the portion of the bore interior surface  34  having the smaller diameter dimension. Thus, the groove  62  is positioned on the base  14  to be radially outside and surrounding the end of a rod or rebar inserted into the base  14  in use of the apparatus  12 . In alternate embodiments of the apparatus, the groove  62  could have a configuration other than the cylindrical configuration shown and described. For example, the groove  62  could have the configuration of a truncated cone. 
         [0030]    The exterior of the base is provided with a plurality of reinforcing ribs  64 . The ribs are spaced circumferentially around the base  14  and extend axially across the base  14  between the cylindrical portion and the cup-shaped portion of the base  14 . The ribs  64  are provided to resist movement of the base second end  26  away from the base center axis  36  in response to an impact force on the base second end  26  that is not substantially axially aligned with the base center axis  36 . 
         [0031]    The band  16  in the preferred embodiment is constructed of a metal material. Other equivalent materials may also be employed in the band construction. Also in the preferred embodiment, the band  16  has a cylindrical configuration with opposite interior  66  and exterior  68  surfaces. The band  16  has an axial length dimension and a width dimension that are complementary to the dimensions of the base annular groove  62  so that the band  16  can be securely mounted to the base  14  by insertion of the band in the groove  62 . In alternate embodiments of the base groove  62 , the configuration of the band  16  would be changed to be complementary to the configuration of the groove. With the band  16  inserted in the groove  62 , the band  16  extends around the end of a rod inserted into the base interior bore  28 . In assembling the band  16  to the base, it is not necessary that the base  14  be molded around the band  16 . The band  16  can be separately assembled to the previously molded base, thereby simplifying the construction of the band  16  and the base  14 . 
         [0032]    The impact member  18  in the preferred embodiment is a circular plate or disk having a general cup-shaped configuration. The preferred embodiment the impact member  18  is constructed of a metal material, although other equivalent materials may be employed. The impact member  18  has opposite first  72  and second  74  surfaces and a perimeter edge  76  that surrounds and separates the two surfaces  72 ,  74 . The first surface  72  has a general convex configuration that is complementary to the general concave configuration of the base second end surface  48 . Thus, in alternate embodiments of the base second end surface  48 , the configuration of the impact member first surface  72  will be complementary to the configuration of the base second end surface  48 . In the general cup-shaped configuration of the impact member  18  shown in the drawing figures, the second surface  74  defines the interior surface surrounding the interior volume of the cup-shaped configuration. The opposite first surface  72  defines the exterior surface of the cup-shaped configuration. In addition, the first surface  72  has a central portion  82  that is complementary to the central portion  52  of the base second end surface. The first surface  72  also has a first tapered annular portion  84  that is complementary to the first tapered annular portion  54  of the base second end surface  48 , and has a second substantially flat annular portion  86  that is complementary to the second annular portion  56  of the base second end surface. 
         [0033]    In further embodiments of the apparatus, the general perimeter configuration of the impact member  18  will match that of the base second end  26 . For example, if the base second end  26  were to have a polygonal configuration at its perimeter, the complementary configuration of the impact member  18  would also be polygonal. 
         [0034]    With the impact member  18  assembled in the apparatus  12 , the impact member first surface  72  engages with the base second end surface  48 . The impact member  18  overlays the band  16  assembled to the base  14 , but is detached from the band. The separate assembly of the impact member  18  to the base  14  without requiring that the impact member  18  be molded and encapsulated in the base  14  further simplifies the construction of the apparatus. 
         [0035]    The cap  22  is constructed of a material that is more resilient and more compressible and stretchable than the material of the base  14 . In the preferred embodiment, the cap  22  is constructed of rubber, although other equivalent materials may be used. The cap  22  has a disk-shaped configuration with opposite first  92  and second  94  surfaces. The outer perimeter of the cap  22  is formed as a circular lip  96 . The lip  96  extends between the cap first  92  and second  94  surfaces and projects axially from the cap first surface  92 . The lip  96  is dimensioned to fit in a tight sealing fit overlaying the base rim  46 . 
         [0036]    A plurality of supporting ribs  98  are formed on the cap first surface  92 . The ribs  98  extend radially outward from the center of the cap to a circular supporting wall  102  that also projects axially from the cap first surface  92 . The circular wall  102  has an axial dimension that positions an end surface  104  of the wall in engagement against the impact member second surface  74  when the cap  22  is assembled to the base  14 . In addition, each of the ribs  98  has an end surface  106  that is shaped complementary to the portion of the impact member second surface  74  that is engaged by the rib surface when the cap  22  is assembled to the base  14 . This engagement of the cap ribs  98  and wall  102  against the impact member  18  securely holds the impact member  18  between the base  14  and cap  22 . In addition, a plurality of webs  108  project axially from the cap first surface  92 . The webs  108  are positioned radially outside the cap circular wall  102  and are dimensioned so that positioning surfaces  112  on the webs  108  will engage against the perimeter edge  76  of the impact member  18  when the base  14  is assembled to the cap  22 . This securely holds the impact member  18  in its radial position relative to the base  14  and the cap  22 . 
         [0037]    The cap  22  is assembled to the base  14  following the assembly of the band  16  and the impact member  18  to the base  14 . With the cap  22  assembled to the base, the cap lip  96  engages around the base rim  46 . The lip  96  and rim  46  can be secured together by adhesives or other bonding agents. They could also be press fit together, RF welded together, or held together by any other equivalent means. In addition, in other embodiments of the apparatus, the band  16 , the impact member  18 , or both the band  16  and impact member  18  could be secured to the base  14  by being injection molded with the base prior to the cap  22  being secured to the base  14 . In still further embodiments, the base  14  and cap  22  could be molded around both the band  16  and impact member  18 . With the cap  22  secured to the base  14 , the band  16  and impact member  18  are completely enclosed in the apparatus  12  and the cap second surface  74  forms an exterior surface of the apparatus. In addition, the open areas between the cap  22  and base  14  defined by the circular wall  102  and the radial ribs  108  and webs  108  on the cap first surface  92  function as air pockets that absorb and diminish an impact force on the cap second surface  94 . 
         [0038]    In use of the apparatus  12  positioned on the end of a rod, for example a concrete reinforcement rod, a force impacting on the apparatus  12  will initially compress the cap  22  and thereby be partially absorbed. The impact force will also be transmitted through the cap  22  to the impact member  18 . A sufficiently large impacting force will cause the impact member  18  to deform from its cup-shaped configuration toward a planar configuration. In addition, the material of the cap  22  will continue to be compressed and spread across the impact member second surface  74 . The combined deformation of the impact member  18  and the compression of the cap  22  distributes the impacting force over an increasing area of the apparatus  12  and thereby further absorbs the impacting force. The impact area of the apparatus  12  is at least the 16 square inch area required by OSHA standards. 
         [0039]    In addition to the above, any impacting force on the apparatus  12  that is not generally axially aligned with the apparatus will have a tendency to move the apparatus  12  from its axial alignment with the end of the rod on which it is used. This tendency to move the apparatus  12  will be resisted by the band  16  mounted on the base  14  and positioned around the distal end of the reinforcing rod received in the base interior bore  28 . The presence of the metal band  16  in the base  14  will resist the tendency of the end of the rod to tear through the material of the base  14  in response to a force impacting with the apparatus  12  that is not generally axially aligned with the apparatus. 
         [0040]    As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.