Abstract:
An improved universal greaseless fifth wheel plate cover and method of installation are disclosed. The fifth wheel plate cover can be retrofitted to almost every existing conventional (greased) fifth wheel, or it could optionally be manufactured into new fifth wheels. The disclosed device comprises a slip plate, which preferably is comprised of a pair of mirror-imaged slip plate members, a plurality of tie down plates, and at least two ramp plate members. The slip plate(s) contain recessed pockets with a plurality of slip plate holes for receiving the plurality of tie down plates. Each tie down plate contains a plurality of corresponding tie down plate holes with sloped edges for contacting a fifth wheel top surface at a distance removed from the bottom edge of the slip plate, thereby ensuring that a weld to fixedly attach the tie down plate to the fifth wheel top surface does not compromise the integrity of the slip plate upon installation.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/881,875 by Roger Dale Price, filed Sep. 24, 2013, which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is generally directed toward an improved greaseless fifth wheel plate cover and method of installation. 
       BACKGROUND OF THE INVENTION 
       [0003]    Fifth wheels are a coupling device for connecting a truck or semi-tractor to a trailer, which may be a van, a piggy-backed van, recreational vehicle, or other pulled vehicle. The bottom side of the trailer has a kingpin extending downward that mates with the bifurcated or horseshow-shaped fifth wheel located on the back of the truck. The fifth wheel locks the kingpin and, thus, the trailer for hauling. During operation, especially during turning, the truck and/or trailer may rotate around the axis of the kingpin locked in the fifth wheel. This rotation creates tremendous friction on the fifth wheel top plate and the plate on the trailer surrounding the kingpin. To facilitate the rotation and minimize wear of the fifth wheel and kingpin plates, conventional fifth wheels utilize grease. The fifth wheel grease may be lost during travel and when the trailer or truck rotates around the kingpin axis. Thus, fifth wheel grease must be applied during regular maintenance or as required. Furthermore, excessive rotation, such as large turns or during docking maneuvers, is known to force grease off the fifth wheel plate. Application of fifth wheel grease may cost the North American trucking industry up to US$20 billion per year. When fifth wheel grease is lost, it typically falls onto the truck, eventually ending up on the roadways, which creates a slick hazard for all motorists. If the fifth wheel is not properly greased or the grease comes off, such as during excessive rotation maneuvers, a “dry spot” could cause the trailer to become stuck in a position that is off center, which may cause excessive tire wear on truck and trailer alike, as well as safety issues for motorists. 
         [0004]    Greaseless fifth wheel plate covers (also sometimes referred to as “lube plates”) have been designed in attempts to address these problems, such as U.S. Pat. No. 5,263,856 to Huehn et al. (the &#39;856 patent, hereby incorporated herein by reference in its entirety) and U.S. Pat. No. 7,036,839 to Hungerlink et al. (the &#39;839 patent, hereby incorporated herein by reference in its entirety). Lube plates have also been designed to be attached on the kingpin plate of a trailer. However, these products and designs have been flawed (see the &#39;839 patent at cols. 1:25-2:22 and references cited therein, each hereby incorporated by reference) and have not been well received in the marketplace for these reasons. Other reasons have been thin, flimsy, and/or inadequate plate coverage design in the known greaseless fifth wheel plates. Another problem with these known greaseless fifth wheel plate covers has been that they have been designed to fit specific fifth wheels. Some designs can only be integrated into a specially manufactured fifth wheel, such as the FONTAINE® 7000CC SERIES® CLEAN-CONNECT® fifth wheel products. The known designs cannot be retrofitted onto all of the millions of fifth wheel bearing trucks on the road and the estimated one million new trucks that are placed on the road each year. A truly universal greaseless fifth wheel plate cover that overcomes the deficits of the existing products and can be utilized by nearly all existing and future conventional fifth wheels is lacking 
       SUMMARY OF THE INVENTION 
       [0005]    One aspect of the present invention is to eliminate the above difficulties and disadvantages by providing an improved universal greaseless fifth wheel plate cover. The universal greaseless fifth wheel plate cover comprising a slip plate, a plurality of tie down plates, and having at least two ramp plates. In some embodiments, the slip plate is comprised of a right hand slip plate and a left hand slip plate. The right hand and left hand slip plates each contain a plurality of recessed pockets, and the recessed pockets contain a plurality of slip plate holes. To facilitate attachment to the fifth wheel, the right hand and left hand slip plates each further contain a ramp plate receiving lip. The right hand and left hand slip plates each are made from one or more of a material having a low coefficient of friction selected from the group consisting of nylon, graphite, or an ultra-high molecular weight polyethylene material. To help prevent a trailer edge from catching on an edge of the slip plates, the right hand and left hand slip plates each have a chamfered outer edge and a chamfered edge on each of the recessed pockets. In further embodiments, the plurality of tie down plates comprise a bottom side facing a top surface of a fifth wheel, a top side facing away from the top surface of said fifth wheel, and a plurality of tie down plate holes. The plurality of tie down plate holes is configured to extend into a slip plate hole and contact the top surface of a fifth wheel. In still further embodiments, the contact edges of the plurality of tie down plate holes are at a sufficient distance away from a slip plate hole edge so that heat from a weld does not compromise the integrity of the slip plate. In yet further embodiments, the plurality of tie down plates are configured to hold the slip plate to the fifth wheel top surface when aligned within a plurality of recessed pockets of the slip plate and welded to the fifth wheel top surface. 
         [0006]    Another aspect of the present invention is to provide an improved tie down plate for affixing a universal greaseless fifth wheel plate cover to a fifth wheel top surface, such that the device can be installed on new fifth wheels as they are manufactured or be retrofitted to almost any existing fifth wheel on the roadways. In some embodiments, the tie down plate comprises a bottom side facing said fifth wheel top surface, a top side facing away from said fifth wheel top surface, and a plurality of tie down plate holes. In further embodiments, the plurality of tie down plate holes is configured to extend into a slip plate hole and contact the fifth wheel top surface. In still further embodiments, the contact edge of the tie down plate holes is at a sufficient distance away from a slip plate hole edge so that heat from a weld does not compromise the integrity of the slip plate. In yet further embodiments, the tie down plate is configured to hold the slip plate to the fifth wheel top surface when aligned within a recessed pocket of the slip plate and welded to the fifth wheel top surface. 
         [0007]    A still further aspect of the present invention is to provide an improved method of installing a universal greaseless fifth wheel plate cover, such that the device can be installed on new fifth wheels as they are manufactured or be retrofitted to almost any existing fifth wheel on the roadways. The method comprises the steps of placing a right hand slip plate and a left hand slip plate on a fifth wheel top surface; placing at least two ramp plates onto the fifth wheel top surface and ramp plate receiving lip of both right hand and left hand slip plates; placing a plurality of tie down plates within a plurality of recessed pockets within both right hand and left hand slip plates; and fixedly attaching said ramp plates and said tie down plates to said fifth wheel top surface. In some embodiments, the method further comprises the step of aligning the right hand and left hand slip plates on the fifth wheel top surface such that the right hand and left hand slip plates meet at an edge away from the ramp plate receiving lips. In further embodiments, the method further comprises the step of aligning a plurality of tie down plate holes on the plurality of tie down plates with a plurality of slip plate holes within the recessed pockets of both right hand and left hand slip plates. In still further embodiments, the step of fixedly attaching the ramp plates and the tie down plates to a fifth wheel top surface is accomplished by welding. In yet still further embodiments, the plurality of tie down plates are welded to a fifth wheel top surface along a plurality of welding edges of the plurality of tie down plate holes. In further embodiments, the plurality of tie down plate holes is significantly smaller than the plurality of slip plate holes. In still further embodiments, the welding of the ramp plates and the tie down plates to a fifth wheel top surface is alternated from welding points on the right hand slip plate and the left hand slip plate to prevent unintentional movement of the universal greaseless fifth wheel plate cover during installation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Further advantages of the invention will become apparent by reference to the detailed description of preferred embodiments when considered in conjunction with the drawings: 
           [0009]      FIG. 1  depicts a perspective view of an exemplary embodiment of the disclosed universal fifth wheel plate cover as installed on a fifth wheel. 
           [0010]      FIG. 2A  is an exploded view of an exemplary embodiment of the disclosed universal fifth wheel plate cover assembly. 
           [0011]      FIG. 2B  is a top elevation view of an exemplary embodiment of a right hand slip plate of the disclosed universal fifth wheel plate cover. 
           [0012]      FIG. 3A  is a top elevation view of an exemplary embodiment of a tie down plate of the disclosed universal fifth wheel plate cover. 
           [0013]      FIG. 3B  is a perspective view of an exemplary embodiment of a tie down plate of the disclosed universal fifth wheel plate cover. 
           [0014]      FIG. 3C  is a side elevation view of an exemplary embodiment of a tie down plate of the disclosed universal fifth wheel plate cover. 
           [0015]      FIG. 4A  is a top elevation view of an exemplary embodiment of a ramp plate of the disclosed universal fifth wheel plate cover. 
           [0016]      FIG. 4B  is a perspective view of an exemplary embodiment of a ramp plate of the disclosed universal fifth wheel plate cover. 
           [0017]      FIG. 4C  is a side elevation view of an exemplary embodiment of a ramp plate of the disclosed universal fifth wheel plate cover. 
           [0018]      FIG. 5  is a cross-section view of a portion of an exemplary embodiment of the disclosed universal fifth wheel plate cover showing a left hand slip plate, recessed pocket, tie down plate, and fifth wheel surface. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    The following detailed description is presented to enable any person skilled in the art to make and use the invention. For purposes of explanation, specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that these specific details are not required to practice the invention. Descriptions of specific applications are provided only as representative examples. Various modifications to the preferred embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the scope of the invention. The present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest possible scope consistent with the principles and features disclosed herein. 
         [0020]    Referring now to the drawings,  FIG. 1  illustrates an exemplary embodiment of the universal fifth wheel plate cover  10  configured for fixedly attaching to a fifth wheel  40  top surface  41 . In one embodiment, the universal fifth wheel plate cover  10  comprises a one-piece slip plate (not shown), a plurality of tie down plates  20 , and at least two ramp plates  30 . In a preferred embodiment, the universal fifth wheel plate cover  10  comprises a multi-piece slip plate in the form of a the right hand slip plate  11  and a left hand slip plate  12 , as shown in  FIGS. 1 and 2 . The right hand slip plate  11  and the left hand slip plate  12  are designed to cover a majority of the fifth wheel  40  top surface  41  area. Preferably, the right hand slip plate  11  and the left hand slip plate  12  are designed to cover a substantial majority of the fifth wheel  40  top surface  41  area, such that slip plates  11 ,  12  meet at junction  9 . By covering more of the fifth wheel  40  top surface  41  area, it is less likely that an edge of a trailer will catch an edge of the right hand slip plate  11  or the left hand slip plate  12  during hitching, unhitching, or hauling. The coverage design of the universal fifth wheel plate cover  10  also provides a large surface area for trailer contact and also for a large wear surface to prolong its useful life. 
         [0021]    The right hand slip plate  11  and the left hand slip plate  12  are made of any suitable material having a low coefficient of friction. In preferred embodiments, the right hand slip plate  11  and the left hand slip plate  12  are made of nylon, graphite, or an ultra-high molecular weight polyethylene (UHMWPE) material. In more preferred embodiments, the right hand slip plate  11  and the left hand slip plate  12  are made of UHMWPE. The right hand slip plate  11  and the left hand slip plate  12  can be made using any suitable method known, for example only and not limiting, heat compression molding, transfer molding, or injection molding. In preferred embodiments, the right hand slip plate  11  and the left hand slip plate  12  are made by heat compression molding. 
         [0022]    The plurality of tie down plates  20  are configured to fit into a plurality of recessed pockets  15  on the top surface (wear surface)  17  of right hand slip plate  11  and left hand slip plate  12 , as can be appreciated in  FIGS. 2A and 5 . Each recessed pocket  15  contains a plurality of slip plate holes  16  created during manufacturing or machined following the chosen manufacturing process. The slip plate holes  16  are configured to align with the tie down plate holes  22 , as can be appreciated in  FIGS. 1 ,  2 A, and  5 . The recessed pockets  15  are preferably constructed to provide a sufficient dimensional depth of possible wear of right hand slip plate  11  and left hand slip plate  12  before a trailer could come into contact with the plurality of tie down plates  20 . In a preferred embodiment, the dimensional depth of recessed pocket surface  19  and tie down plate  20  is 0.060 of an inch, while the total dimensional depth of right hand slip plate  11  and left hand slip plate  12  is 5/16ths of an inch, thus providing more than 0.19 of an inch of possible dimensional depth wear of the universal fifth wheel plate cover  10 . 
         [0023]    Referring to  FIGS. 3A-3C , tie down plates  20  are designed to provide sufficient hold of the universal fifth wheel plate cover  10  to the top surface  41  of a fifth wheel  40  when fixedly attached thereto while simultaneously providing maximum slip plate wear surface  17  to slip plates  11 ,  12 . In a preferred embodiment, tie down plates  20  are comprised of a four-sided stainless steel member having three extruded tie down plate holes  22 , three fifth wheel contact surfaces  23 , three welding edges  25 , long sides  27 ,  28 , short sides  29   a,    29   b,  tie down plate top surface  21 , and tie down plate bottom surface  26 . Tie down plates  20  are placed inside recessed pockets  15  with tie down plate bottom surface  26  in contact with recessed pocket surface  19  and tie down plate top surface  21  facing toward slip plate wear surface  17 . Other embodiments may be configured to have fewer or more extruded tie down plate holes  22 , fifth wheel contact surfaces  23 , and/or welding edges  25 . 
         [0024]    Tie down plates  20  can be made of any rigid material. In preferred embodiments, tie down plates  20  are made of metal capable of being fixedly attached to the top surface  41  of a fifth wheel  40  by welding. In more preferred embodiments, tie down plates  20  are made of stainless steel. Tie down plates  20  can be made by any known method in the art. In preferred embodiments, tie down plates  20  are made by stamping process. Tie down plate holes  22  are preferably made by punching and extrusion processes, but may be made by any suitable method known in the art. As can be seen in  FIGS. 2A and 5 , tie down plate holes  22  are significantly smaller than slip plate holes  16 , which will discussed in more detail below. 
         [0025]    In preferred embodiments, the universal fifth wheel plate cover  10  comprises eight recessed pockets  15  with eight corresponding tie down plates  20 . Thus, right hand slip plate  11  and left hand slip plate  12  each contain four recessed pockets  15  with eight corresponding tie down plates  20 , such as shown in  FIGS. 1 ,  2 A, and  2 B. However, it should be readily understood that fewer or more would work sufficiently for fixedly attaching the universal fifth wheel plate cover  10  to the top surface  41  of a fifth wheel  40 . As can be appreciated in  FIG. 2B , the entire slip plate wear surface  17  preferably has a chamfered peripheral edge  18   a.  As best seen in  FIG. 5 , the recessed pocket edges  18   b  of slip plate wear surface  17  are also preferably chamfered. The chamfered edges  18   a,    18   b  ensure that it is less likely that an edge of a trailer will catch one of the universal fifth wheel plate cover  10  edges  18   a,    18   b  during hitching, unhitching, or hauling. 
         [0026]      FIG. 4  illustrates an exemplary embodiment of a ramp plate  30  comprising short sides  31 ,  32 ; long sides  33 ,  34 ; ramp plate top surface  35 ; and ramp plate bottom surface  36 . Ramp plates  30  can be made of any rigid material. In preferred embodiments, ramp plates  30  are made of metal capable of being fixedly attached to the top surface  41  of a fifth wheel  40  by welding. In more preferred embodiments, ramp plates  30  are made of stainless steel. Ramp plates  30  can be made by any known method in the art. In preferred embodiments, ramp plates  30  are made by stamping process. Ramp plates  30  are preferably constructed to have a dimensional depth that will prevent an edge of a trailer from catching one of the universal fifth wheel plate cover  10  edges below chamfered peripheral edge  18   a,  especially during hitching. 
         [0027]    As shown in  FIG. 2B , right hand slip plate  11  and left hand slip plate  12  (not shown) each comprise a ramp plate receiving lip  13  at the side closest to the bifurcated portion of a fifth wheel  40 . In some embodiments, ramp plate receiving lip  13  is substantially flat (see  FIG. 2B ), while ramp plate receiving lip  13  may be gently sloped in other embodiments (see  FIG. 2A ). Ramp plates  30  serve at least two purposes for universal fifth wheel plate cover  10 . First, ramp plates  30  provide a rigid and durable surface for a trailer edge to contact during the hitching process to guide the trailer on top of slip plate wear surface  17 . Second, ramp plate  30  is fixedly attached to the top surface  41  of a fifth wheel  40  (preferably by welding along short sides  31 ,  32  and long side  33  to the top surface  41  of a fifth wheel  40 ; note that the weld(s) does not have to be continuous or comprise 100% of the available edges of sides  31 - 33 ), which provides support to hold the front edge of universal fifth wheel plate cover  10  to the fifth wheel  40  at the point most susceptible to mechanical failure by encountering a trailer edge during the hitching process. 
         [0028]    Referring now to  FIG. 1  in conjunction with  FIG. 5 , which is a cross-section through an assembled universal fifth wheel plate cover  10  on a fifth wheel  40  as seen at LINE A-A in  FIG. 1 , a better understanding of the installation process can be conveyed. First, right hand slip plate  11  and left hand slip plate  12  are placed and aligned as desired on a fifth wheel  40  top surface  41  (preferably clean and dry), as illustrated in  FIG. 1 . Then, ramp plates  30  are applied to ramp plate receiving lip  13  of both right hand slip plate  11  and left hand slip plate  12 . Then, a plurality of tie down plates  20  are placed within the recessed pockets of both right hand slip plate  11  and left hand slip plate  12 . Next, ramp plates  30  and tie down plates  20  are fixedly attached to the top surface  41  of fifth wheel  40 . In preferred embodiments, ramp plates  30  and tie down plates  20  are welded to the top surface  41  of fifth wheel  40 . The sequence of welding is not important, but it may be advantageous to alternate welding ramp plates  30  and/or tie down plates  20  on the right hand slip plate  11  and the left hand slip plate  12  to prevent unintentional movement of the slip plates  11 , 12  during the installation process. Ramp plates  30  are welded to the top surface  41  of fifth wheel  40  along sides  31 ,  32 , and  33 . It should be understood that 100% of the available welding edge surface of ramp plate  30  does not have to be welded to ensure a proper hold of the ramp plates  30 , the right hand slip plate  11 , or the left hand slip plate  12 . In preferred embodiments, welding is accomplished on between 40-100% of the available welding edge surface of the ramp plates  30 . In more preferred embodiments, welding is accomplished on between 50-90% of the available welding edge surface of the ramp plates  30 . 
         [0029]    Tie down plates  20  are welded to the top surface  41  of fifth wheel  40  at tie down plate holes  22  along the welding edges  25 . It should be understood that 100% of the available welding edge surface of the welding edges  25  does not have to be welded to ensure a proper hold of the tie down plates  20 , the right hand slip plate  11 , or the left hand slip plate  12 . In preferred embodiments, welding is accomplished on between 40-100% of the available welding edge surface of the welding edges  25 . In more preferred embodiments, welding is accomplished on between 40-60% of the available welding edge surface of the welding edges  25 . As previously mentioned, tie down plate holes  22  are significantly smaller than slip plate holes  16 . The smaller diameter for tie down plate holes  22  results in buffer space  24  between the outer edge  16   a  of slip plate holes  16  and fifth wheel contact surfaces  23 . Applying a weld to welding edges  25  creates a significant amount of heat locally that could potentially damage, destroy, or otherwise compromise the integrity of a slip plates  11 , 12 . It can be appreciated from  FIG. 5  that buffer space  24  decreases the chance of compromising the integrity of a slip plates  11 , 12  during installation due to heat from welding at welding edges  25 . To further decrease the chance of compromising the integrity of a slip plates  11 , 12  during installation, water or a wet rag can be used to cool each weld after it is made. Once ramp plates  30  and the plurality of tie down plates  20  have been welded to the top surface  41  of fifth wheel  40 , installation of universal fifth wheel plate cover  10  is complete. It should be appreciated that installation of universal fifth wheel plate cover  10  by the welding method is designed to permit retrofitting of almost every known fifth wheel  40  on the roadways. No special tools, fasteners, seat plates, or drilling of fifth wheel  40  to be retrofitted is required for installation of the universal fifth wheel plate cover  10  disclosed herein. 
         [0030]    The installed universal fifth wheel plate cover  10  is designed to be durable and to require minimum maintenance. As previously mentioned, the available dimensional depth of the wear surface  17  for vertical wear is more than 0.19 of an inch in preferred embodiments. Based on tests (discussed in the Examples, below), this dimension is anticipated to provide multiple years of wear without the need for replacement. Maintenance is simple; merely wash dirt and road grime from universal fifth wheel plate cover  10  from time to time when washing or servicing the vehicle on which it is installed. If the universal fifth wheel plate cover  10  has been used in an environment that could lead to sand being deposited on it, the universal fifth wheel plate cover  10  should be washed at the next convenient opportunity as sand could cause excessive wear on the slip plates  11 , 12 . 
       EXAMPLE 1 
       [0031]    An embodiment of the universal fifth wheel plate cover  10  was installed for testing on a fifth wheel  40  previously installed onto a truck following the method described above. The universal fifth wheel plate cover  10  used comprised a right hand slip plate  11  and a left hand slip plate  12 , each having three recessed pockets for receiving tie down plates  20  (a total of nine tie down plates  20  were used in this configuration) and each having a ramp plate receiving lip  13 , and two ramp plates  30 . The tie down plates  20  were welded to the top surface  41  of the fifth wheel  40  at welding edges  25  of the tie down plate holes  22 . Approximately 50% of the welding edge  25  received welding. The ramp plates  30  were welded to the top surface  41  of the fifth wheel  40  at sides  31 ,  32 , and  33 . The right hand slip plate  11  and the left hand slip plate  12  were made of UHMWPE material. 
         [0032]    The installed embodiment of the universal fifth wheel plate cover  10  did not comprise chamfered edges, and it was noticed that trailer edges sometimes would catch an edge of the right hand slip plate  11  and/or the left hand slip plate  12 . These events never resulted in a failure of the universal fifth wheel plate cover  10  (pulling off the universal fifth wheel plate cover  10  from the fifth wheel  40 ). It was found that the top portion (the portion away from the ramp plates  30 ) of the universal fifth wheel plate cover  10  was subject to being pulled away more than the bottom edge being held down by the welded ramp plates. To add extra hold at the top portion of the universal fifth wheel plate cover  10 , a small countersunk hole was made in the top portion of each the right hand slip plate  11  and/or the left hand slip plate  12  and two stainless steel washers were welded to the top surface  41  of the fifth wheel  40  along the edge of the top portion of both the right hand slip plate  11  and/or the left hand slip plate  12 . It was found that adding chamfered edges  18   a , 18   b  and a fourth tie down plate  20  (and corresponding fourth recessed pocket to each slip plate  11 , 12 ) alleviated the stress applied to the top portion, as shown in  FIG. 1 . 
         [0033]    The installed embodiment of the universal fifth wheel plate cover  10  was made with at least 0.19 of an inch of dimensional depth of the wear surface  17  for vertical wear. The installed embodiment has shown minimum wear on the wear surface  17  after testing that has continued for more than 36 months. 
       EXAMPLE 2 
       [0034]    A further embodiment of the universal fifth wheel plate cover  10  was installed for testing on a fifth wheel  40  previously installed onto a truck following the method described above. This universal fifth wheel plate cover  10  comprised a right hand slip plate  11  and a left hand slip plate  12 , each having three recessed pockets for receiving tie down plates  20  (a total of nine tie down plates  20  were used in this configuration) and each having a ramp plate receiving lip  13 , and two ramp plates  30 . 
         [0035]    The tie down plates  20  were welded to the top surface  41  of the fifth wheel  40  at welding edges  25  of the tie down plate holes  22 . Approximately 50% of the welding edge  25  received welding. The ramp plates  30  were welded to the top surface  41  of the fifth wheel  40  at sides  31 ,  32 , and  33 . All edges of the right hand slip plate  11  and the left hand slip plate  12  were chamfered  18   a , 18   b  to prevent catching by a trailer edge. The right hand slip plate  11  and the left hand slip plate  12  were made of UHMWPE material. This installed embodiment of the universal fifth wheel plate cover  10  has shown no visible wear on the wear surface  17  after testing that has continued for more than four months. 
         [0036]    The terms “comprising,” “including,” and “having,” as used in the claims and specification herein, shall be considered as indicating an open group that may include other elements not specified. The terms “a,” “an,” and the singular forms of words shall be taken to include the plural form of the same words, such that the terms mean that one or more of something is provided. The term “one” or “single” may be used to indicate that one and only one of something is intended. Similarly, other specific integer values, such as “two,” may be used when a specific number of things is intended. The terms “preferably,” “preferred,” “prefer,” “optionally,” “may,” and similar terms are used to indicate that an item, condition or step being referred to is an optional (not required) feature of the invention. 
         [0037]    The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention. It will be apparent to one of ordinary skill in the art that methods, devices, device elements, materials, procedures and techniques other than those specifically described herein can be applied to the practice of the invention as broadly disclosed herein without resort to undue experimentation. All art-known functional equivalents of methods, devices, device elements, materials, procedures and techniques described herein are intended to be encompassed by this invention. Whenever a range is disclosed, all subranges and individual values are intended to be encompassed. This invention is not to be limited by the embodiments disclosed, including any shown in the drawings or exemplified in the specification, which are given by way of example and not of limitation. 
         [0038]    While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. 
         [0039]    All references throughout this application, for example patent documents including issued or granted patents or equivalents, patent application publications, and non-patent literature documents or other source material, are hereby incorporated by reference herein in their entireties, as though individually incorporated by reference, to the extent each reference is at least partially not inconsistent with the disclosure in the present application (for example, a reference that is partially inconsistent is incorporated by reference except for the partially inconsistent portion of the reference).