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REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present patent application is a continuation-in-part of, and hereby claims priority to, U.S. Non-Provisional application Ser. No. 12/660,694, filed Mar. 2, 2010 entitled “Three Dimensional Connection System For Bed Frame”, which in turn, claims priority from U.S. Provisional Application Ser. No. 61/165,493 filed Mar. 31, 2009. The present application also hereby claims priority to U.S. Provisional Application Ser. No. 61/339,226, filed Mar. 2, 2010 entitled “Bed Frame Having Protective Plastic Coating”. Applicants claim the benefits of 35 U.S.C. §120 as to said Non-Provisional Application, and the benefits of 35 U.S.C. §119 as to said Provisional Applications, and the entire disclosures of all applications are incorporated herein by reference in their entireties. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a bed frame for supporting a mattress or mattress set and, more particularly, to a bed frame that has a protective plastic casing that covers the structural components of the bed frame. 
       BACKGROUND OF THE INVENTION 
       [0003]    There are currently in use conventional bed frame assemblies that are used for supporting a mattress or mattress set and such bed frame assemblies are normally made up of two side rails and at least one cross member. The bed frame supports the load of a mattress set by means of multiple support legs. 
         [0004]    With many bed frames, the side rails and cross members are made of a metal, generally iron or steel, and the overall frame therefore has multiple sharp edges for the metal components. Further, the use of metal makes the bed frame a difficult platform on which the box spring and mattress are slid in assembling a bed. The metal material for bed frames is not particularly lubricious and therefore hampers the sliding of a box spring over the assembled frame and there is the possibility that one of the sharp edges of the bed frame will cause a tear in the box spring or mattress material. 
         [0005]    Accordingly, it would be advantageous to provide a covering for a bed frame that is both protective of sharp edges as well as facilitate the sliding of a box spring over the bed frame in the assembly of a completed bed. 
       SUMMARY OF THE INVENTION 
       [0006]    A feature of the present bed frame is that the metal frame is encased in plastic, thereby allowing the box spring and mattress to easily slide in place on top of the frame without contact with the metal, that is, along some portion or all of the length of a side rail or cross rail, the rail is totally surrounded by a plastic shield. The side rails and the cross rails are encased in a plastic shield and there are plastic injection molded end caps. With the present invention, therefore, the side and/or cross rail for a bed frame can be encased with plastic shields at the point of manufacture such that the rails are shipped with the plastic shields assembled thereto. As such, each step of the assembly of the bed frame using a plastic shielded component can have the advantage of the present invention since that assembly does not need to deal with hard steel components. 
         [0007]    In an exemplary embodiment, the side rails are made from one or more rail steel angle iron pieces, however any structural metal beam can be used with the present invention including rolled tubing and folded strips. The plastic is a more lubricious surface than the steel and therefore the task is made simpler requiring less exertion and stress. Secondly, the plastic is not abrasive to the fabric of the bedding and so the material is protected from damage or wear. Thirdly, the plastic serves to make the frame quiet by inhibiting any metal on metal squeaking. The staples or tacks in the box spring can make sound on a metal bed frame. The plastic forms an entirely flat platform for supporting the bedding. In an exemplary embodiment, there may be grooves formed on the surface of the plastic that serve to further deaden any sounds and inhibit vibration. 
         [0008]    In an exemplary embodiment, the bed frame has a double angle iron side rail encased in a plastic extrusion. This side rail is more rigid because it has a tall vertical proportion. The plastic serves to dress the frame and make it more like traditional finished furniture as well as to make the steel more comfortable and safer to handle because it is softer and has few edges. 
         [0009]    The cross rails are preferred to also be made of two piece of angle iron covered by a plastic extrusion. This allows the cross rail to also present the appearance of a finished part. The ends of the cross rails are capped with an injection molded end caps. All metal rails, both assembled and unassembled, are encased by plastic. The plastic shield could be manufacture in many ways including injection molding, insert injection mold, and coating. A preferred method of manufacture is to extrude the shield. Ribs are utilized on the inside of the extrusion to support the shaping and hold the internal metal structure in place. These ribs can take a number of different configurations. The preferred rib configuration is to have two ribs hanging straight down from the curved surface to contact the metal structure. These would be positioned only about a 0.25 inch inboard of the outer edges of the metal. In this way, the ribs will not fall off the edge but are also as short as possible. This will help with the thickness and consistency during manufacture. 
         [0010]    In a further embodiment, the side rail of the bed frame is constructed of a single L shaped angle iron completely encased in plastic. The vertical flange of the angle iron extends upwardly to form a ridge to retain the bedding from side to side movement. The plastic extends downward below the horizontal portion of the angle. In this way, the side rail has a larger visual impact on the appearance of the bedding. Also this serves the function of covering the cut end of the cross rails at the point they connect to the side rails. 
         [0011]    In addition the plastic overhang allows for the addition of lighting where the wiring and the fixtures are shielded from view. This light serves as a safety feature but also makes the bed more visually exciting. The plastic shield could be manufactured in many ways including injection molding, insert injection mold, and coating. A preferred method of manufacture is to extrude the encasement. Ribs are required on the inside of the extrusion to support this shaping and hold the internal metal structure in place. These ribs can be provided in a number of different configurations. 
         [0012]    In a further embodiment, the side rail of the bed frame is constructed of a single L shaped angle iron completely encased in plastic with the vertical flange of the angle iron extending downwardly such that the leg of the angle perpendicular to the floor is positioned below the bottom surface of the bedding. In this case, the plastic is extended above the vertical member of the angle iron to form a ridge that retains the bedding against side to side movement. In this way, the side rail has a larger visual impact on the appearance of the bedding. 
         [0013]    Also the rail downward turned flange of the angle iron serves the function of covering the cut end of the cross rails at the point they connect to the side rails. In addition the plastic overhang allows for the addition of lighting where the wiring and the fixtures are shielded from view. As such, the geometry of the rail that allow for the rails rigidity is all below the bedding. 
         [0014]    The upstanding rigid portion can be much abbreviated in height because it is only a retainer. This is critical when the box spring has pull out storage drawers that can be blocked by tall side rails. The plastic shield could be manufactured in many ways including injection molding, insert injection mold, and coating. A preferred method of manufacture is to extrude the encasement. The upstanding ridge of plastic could take many forms. The preferred embodiment would be a hollow loop within extending from the main body of the plastic shield. Within the upstanding loop there is a ribbed reinforcement to provide strength to the otherwise unsupported member. 
         [0015]    As a still further exemplary embodiment, since the plastic shields are affixed to the bed frame component at the manufacturers location, the manufacturer can provide the bed shields in a variety of standard or custom colors so that the ultimate user may have a bed frame components that are of a particular color to match the room or to identify the component as applicable for a particular size or type of bed frame. Thus, the manufacturer can use a customer-selected color of plastic shield and that specific color bed frame components can be boxed up and shipped to the customer with the desired color. 
         [0016]    These and other features and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is an exploded view illustrating a cross rail bed frame member having a protective plastic end cap; 
           [0018]      FIG. 2  is an exploded view illustrating a side rail bed frame member having a protective plastic end cap; 
           [0019]      FIG. 3  is a cross sectional view of a side rail encased in plastic made with two angle irons; 
           [0020]      FIG. 4  is a cross sectional view of a cross rail encased in plastic made with two angle irons; 
           [0021]      FIGS. 5 and 5A  are a cross sectional view and an enlarged cross sectional view of a side rail having a plastic shield with surface grooves; 
           [0022]      FIGS. 6 and 6A  are a cross sectional view and an enlarged cross sectional view of a cross rail having a plastic shield with surface grooves; 
           [0023]      FIG. 7  is a schematic view illustrating a mattress/foundation sliding on an entirely plastic encased bed frame; 
           [0024]      FIG. 8  is a cross sectional view of a side rail made with an angle iron encased in plastic having one upturned flange with a plastic shield blocking the end of a cross rail; 
           [0025]      FIG. 9  is a perspective view illustrating the visual difference between a raw angle iron and the plastic encasement covering the angle iron; 
           [0026]      FIG. 10  is a cross sectional view of a side rail of  FIG. 8  with a lighting strip concealed behind the plastic shield; 
           [0027]      FIG. 11  is a perspective view illustrating bed frame and mattress with the concealed light of  FIG. 10 ; 
           [0028]      FIG. 12  is a cross sectional view of a side rail made with an angle iron encased in plastic having one downturned flange with a plastic shield blocking the end of a cross rail with a plastic lip for retaining the bedding; 
           [0029]      FIG. 13  is a cross sectional view of a side rail of  FIG. 12  with a lighting strip concealed behind the downturned flange of the angle iron; 
           [0030]      FIG. 14  is a cross sectional view of a side rail of  FIG. 12  having standing ribs to support the outer portion of the plastic shield; and 
           [0031]      FIG. 15  is a cross sectional view of a side rail of  FIG. 12  having a different configuration of outer portion of the plastic shield than the embodiment of  FIG. 14 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    Turning to  FIG. 1 , there is shown an exploded view illustrating a bed frame cross rail  10  having a protective plastic end cap  12  that fits over the end of the cross rail  10  to cover the sharp edges that are present at the ends of the cross rail  10 . As can be seen, the cross rail  10  is comprised of two angle irons  14 ,  16  secured together by means such a rivets  18  to form a T-shape. As is well known, the ends of such cross rails result in sharp edges of the angle irons  14 ,  16  that can be hazardous to a person striking a sharp edge. The end cap  12  is also therefore a T-shape and fits over the ends of the cross rails  10  and may include an enlarged pocket  20  to enable the end cap  12  to slip over a rivet where necessary. Although only one end cap  12  is illustrated, both ends of the cross rails  10  may be protected by an end cap  12 . 
         [0033]    Next, in  FIG. 2 , there is an exploded view of a side rail  22  and a plastic end cap  24  that fits over the end of the side rail  22 . In this embodiment, again, there are two angle irons  26 ,  28  that are secured together forming a combined vertical flange  30  and an overlapping inwardly directed horizontal flange  32 . There is also a plastic shield  34  that covers the external surface of the vertical flange  30  and abuts against the end cap  24  when the end cap  24  is slid onto the end of the side rail  22 , thereby fully covering the exterior surface of the vertical flange  30 . A fastener  36  can be used to secure the end cap  24  to the side rail  22  by passing though the end cap  24  and a hole  38  in the side rail  22 . The exterior surface  40  of the end cap  24  can be designed to be of the same curvature as the exterior surface  42  of the plastic shield  34  so that the two components meet in a smooth junction. 
         [0034]    Turning next to  FIG. 3 , there is shown a cross sectional view of a side rail  44  that, again, is constructed of two angle irons  46 ,  48  secured together. As can be seen, the combined angle irons  46 ,  48  forms an overlapping horizontal flange  50  and a combined adding vertical flange  52  that is twice the length of a vertical flange of the angle irons  46 ,  48 . A plastic shield  54  fully surrounds the cross section of the side rail  44  such that the metal side rail  44  is completely covered and thus the cold steel or other metal is easier to handle and is more esthetically pleasing. 
         [0035]    In the orientation of  FIG. 3 , the plastic shield  54  has an exterior portion  56  that is held away or displaced from the vertical flange  52  by means of ribs  58 ,  60  and which can be molded into the plastic shield  54 . Since the plastic shield  54  is, in the embodiment of  FIG. 3 , unbroken, it can be slid along the longitudinal length of the side rail  44  in order to install the plastic shield  54  to the side rail  44 . 
         [0036]    Turning next to  FIG. 4 , there is a cross sectional view of a cross rail  62  that is, again, made up of two angle irons  64 ,  66  that are secured together. In this embodiment, since the bed frame component is a cross rail, the cross rail  62  is oriented such that the upper, horizontal flange  68  is twice the length of a single flange of either of the angle irons  64 ,  66  and the vertical flange  70  overlaps the flanges of the angle irons  64 ,  66 . Again, however, there is a plastic shield  72  that surrounds the entire cross section of the cross rail  62  so as to fully cover the metal angle irons  64 ,  66 . 
         [0037]    It should be noted, that while the description of a cross rail or side rail component making up a bed frame may be described as being comprised of two angle irons secured together, the present invention is equally applicable to a side rail or cross rail being provided as a single, unitary construction. 
         [0038]    In  FIGS. 5 and 5A , there is cross sectional view of a side rail and an enlarged cross section of a side rail  44  with the plastic shield  54  as shown in the embodiment of  FIG. 3 , however, the external surface  74  of the exterior portion  56  is curved outwardly and has surface grooves  76  formed thereon. The surface grooves  76  serve to further deaden any sounds and inhibit vibration. In addition, since the plastic shields may be extruded and have a shiny exterior finish, the use of the surface grooves  76  creates a finish that is less susceptible to marring or surface damage. 
         [0039]    In  FIGS. 6 and 6A , there is cross sectional view of the cross rail  62  and an enlarged cross section of the cross rail  62  with the plastic shield  72  as shown in the embodiment of  FIG. 4 , however, the external surface  78  of the upper portion  80  of the plastic shield has surface grooves  82  formed thereon. 
         [0040]    Next in  FIG. 7 , there is a schematic view of a box spring  84  being slid onto a bed frame  86 . As can be seen, the box spring  84  slides in the direction of the arrow A along the side rails  88 . In accordance with the present invention, the side rails  88  are fully covered by a plastic shield  90 , including end caps  92  such that the box spring  84  can slide easily and in a more lubricious manner than if the box spring  84  were sliding along raw steel side rails. The protective plastic end caps  92  prevent the otherwise sharp edges of the side rails  88  from cutting into the box spring and the smooth sliding action along the plastic shields  90  of the side rails  88  also minimizes damage to the box spring. 
         [0041]    Turning to  FIG. 8 , there is shown a cross sectional view of a side rail  94  that is an L-shaped configuration, such as an angle iron, with a horizontal flange  96  positioned to underlie a box spring (not shown) and a vertical flange  98  extending upwardly from the horizontal flange  96  and adapted to be positioned proximate to, and run along, the outside edge of a box spring. Again, there is a plastic shield  100  that fully encases the side rail  94  so as to enclose the side rail  94  entirely.  FIG. 8  also shows a cross rail  102  of a bed frame and, as can be seen, there is a downwardly directed portion  104  of the plastic shield  100  that extends below the horizontal flange  96  and which covers the outer end  106  of the cross rail  102  to provide protection again a person inadvertently encountering that outer end  106  and being injured. 
         [0042]    As such, the plastic shield  100  not only encases the side rail  94  for protection to make the side rail  94  easier to handle and maneuver, but when the side rail  94  is assembled in constructing a bed frame, the same plastic shield  100  affords protection for persons by covering the outer end  106  of a cross rail  102 . 
         [0043]    In the embodiment of  FIG. 8 , there can also be seen a rib  108  that contacts the vertical flange  98  to position the exterior portion  110  of the plastic shield  100  outwardly from the vertical flange  98  and also a reinforcing rib  112  that adds strength and rigidity to the downwardly directed portion  104 . 
         [0044]    Turning then to  FIG. 9 , then is shown a perspective view of the side rail  94  of  FIG. 8  with a portion of the plastic shield  100  removed so that a distinction can be seen between the easily handled and protected portion of the side rail  94  protected by the plastic shield  100  and the bare portion of the side rail  94  where there is no such protection. 
         [0045]    Turning to  FIG. 10 , there is a cross sectional view of a further exemplary embodiment of the side rail  94  of  FIG. 8 . In  FIG. 10 , a light  114 , such as a fluorescent light, is located underneath the horizontal flange  96  and thus is underneath the box spring and mattress and is located interior of the downwardly directed portion  104  and is therefore in a protective location where the light  114  cannot be easily kicked or otherwise struck by a person or objects nearing the bed frame. 
         [0046]    In  FIG. 11 , taken along with  FIG. 10 , there is a perspective view of a box spring  116  and showing the side rail  94  having a plastic shield  100  and illustrating the effect of the indirect lighting where the light rays  118  are directed downwardly and inwardly by the downwardly directed portion  104  of the plastic shield  100  thereby creating a desirable lighting effect. 
         [0047]    Turning next to  FIG. 12 , there is shown a cross sectional view of an alternative embodiment of a side rail  120  that is an L-shaped configuration, such as an angle iron, with a horizontal flange  122  positioned to underlie a box spring  124  and a vertical flange  126  extending downwardly from the horizontal flange  122 , that is, the vertical flange  126  extends beneath the box spring  124  and is adapted to be positioned proximate to, and run along, the outside edge of the box spring  124 . 
         [0048]    Again, there is a plastic shield  128  that fully encases the side rail  120  so as to enclose the side rail  120  entirely.  FIG. 12  also shows a cross rail  130  of a bed frame and, as can be seen, there is a upwardly directed portion  132  of the plastic shield  128  that extends above the horizontal flange  122  and which is located proximate to the box spring  124  and prevents the box spring  124  from movement in a lateral direction. 
         [0049]    As such, the plastic shield  128  not only encases the side rail  120  for protection to make the side rail  120  easier to handle and maneuver, but when the side rail  120  is assembled in constructing a bed frame, the same plastic shield  128  affords stability against lateral movement of the box spring  124  as well as protection against persons contacting the sharp outer end  134  of the cross rail  130 . 
         [0050]    In the embodiment of  FIG. 12 , there can also be seen a rib  136  that contacts the vertical flange  126  to position the exterior portion  138  of the plastic shield  128  outwardly of the vertical flange  126  and also a reinforcing rib  140  that adds strength and rigidity to the upwardly directed portion  132 . 
         [0051]    Turning then to  FIG. 13 , there is shown a cross sectional view of the side rail  120  of  FIG. 12  further including a light  142  that can be positioned beneath the horizontal flange  122  and behind the vertical flange  126  so as to protect the light  142  from damage by persons or objects striking the light  142 . 
         [0052]    In  FIG. 14 , there is a side rail  120  that is constructed the same as in the  FIG. 12  embodiment, that is, the side rail  120  is an L-shaped configuration, such as an angle iron, with the horizontal flange  122  positioned to underlie a box spring and the vertical flange  126  extending downwardly from the horizontal flange  122 . 
         [0053]    With the  FIG. 14  embodiment, however the plastic shield  144  is of a slightly different configuration, that is, the upwardly directed portion  146  is more circular in appearance and the exterior portion  148  of the plastic shield  144  is concave inwardly in design and there are two ribs  148  that extend inwardly from the exterior portion  148  and contact the vertical flange  126  to add strength and rigidity to the plastic shield  144 . 
         [0054]    Finally, in  FIG. 15 , there is a further embodiment wherein the plastic shield  152  has an outer portion  154  with a lower section  156  that is generally parallel to the vertical flange  126  with an upper section  158  that curves inwardly toward the vertical flange  126 , such that an upper rib  160  is shorter that a lower rib  162 . 
         [0055]    While the present invention has been set forth in terms of a specific embodiment of embodiments, it will be understood that the present plastic shielding system for a bed frame herein disclosed may be modified or altered by those skilled in the art to other configurations. Accordingly, the invention is to be broadly construed and limited only by the scope and spirit of the claims appended hereto.

Summary:
A bed frame wherein the side rail and/or cross rails are fully encased in plastic shields. A plastic shield or shields cover the entire cross sectional area of the side and cross rails so that the side rail and cross rails are easy to handle and esthetically pleasing. The system avoids the need for a person to handle cold, sometimes dirty, steel and the cross and side rails may be T-shaped or L-shaped angle irons, or other configurations and covered with plastic shields. With the plastic shields, the steel members need not be finished since the outer appearance of the steel is encased by the plastic shields and not seen by persons.