Abstract:
A horizontally and vertically adjustable Class IV certifiable trailer hitch assembly that has a 16 inch range of 12 vertical adjustments in the most common vertical increments. The main body of the trail hitch assembly, the trailer hitch minus the hitch ball components, has a two part connectable construction of a support member and a ball mount member, each of which can be rotated 180 degrees before connection. In any of these four configurations an optional coupling plate may be utilized.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a extremely stout trailer hitch assembly capable of meeting or exceeding the SAE J-84-V5 testing requirements for a class IV trailer hitch. 
         [0002]    Class IV hitches are for safely handling up to 10,000 lbs. of gross trailer weight (GTW) and 1,000 to 1,200 lbs. of tongue weight. These are used for serious towing needs, generally commercial in nature such as for contractors hauling heavy machinery or used at the extreme end of personal recreational like large boats or trailers. Generally, to be able to tow a class IV load requires heavier duty diesel vehicles dedicated to the towing of these loads. For this reason the users mate a hitch specifically built to engage their receiver and maintain the ball of the hitch at the precise height off the ground to matingly engage the coupler of the towed trailer such that the trailer rides in an approximately level configuration so as to properly set the tongue weight of the trailer for that vehicle. There is a range of height of approximately 16 inches between the extremes in the majority of common tow vehicle&#39;s receiver height and their trailer&#39;s hitch height. This may represent either a drop or rise in height with relation to the horizontal centerline of the receiver. 
         [0003]    The conventional class IV trailer hitch has a receiver engagement tube that is welded to a unitary curved tang with an orifice for the trailer ball, so as to form a “stinger.” They are available in different drop or rise heights, commonly in one or two inch increments and there is only a single weld in the assembly to maintain strength. It is critical for the safety of the vehicle and the trailer that the hitch used has the proper drop or rise. With the rise in recreational equipment as the post war baby boomers approach retirement many people need multiple hitches to safely tow their boats, travel trailers, snow machines, ATVs etc. 
         [0004]    Henceforth, an adjustable class IV trailer hitch assembly would fulfill a long felt need in the towing industry. This new invention utilizes and combines known and new technologies in a unique and novel configuration to overcome the aforementioned problems and accomplish this. 
       SUMMARY OF THE INVENTION 
       [0005]    The general purpose of the present invention, which will be described subsequently in greater detail, is to provide an adjustable class IV trailer hitch assembly that is able provide up to 16 inches of combined drop and rise from the horizontal centerline of a trailer hitch receiver. It has many of the advantages mentioned heretofore and many novel features that result in a new adjustable class IV trailer hitch which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof. 
         [0006]    In accordance with the invention, an object of the present invention is to provide an improved class IV trailer hitch assembly that is capable for adjustment above or below the receiver in the most common drop and rise stepped configurations. 
         [0007]    It is another object of this invention to provide an improved adjustable class IV trailer hitch capable of meeting or exceeding the SAE J684 (Rev July 2005) and V-5 test requirements. 
         [0008]    It is a further object of this invention to provide a class IV trailer hitch assembly that allows for the adjustability of the hitch ball in the coupling base by the rotatable engagement of a an insert ring. 
         [0009]    It is still a further object of this invention to provide for a class IV trailer hitch assembly having a coupling plate designed to withstand the rigors of off angle low speed coupling without distortion of its lateral position. 
         [0010]    The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a front top perspective view of the trailer hitch assembly showing the general arrangement of all components; 
           [0012]      FIG. 2  is a front bottom perspective view of the trailer hitch assembly showing the general arrangement of all components; 
           [0013]      FIG. 3  is a top view of the trailer hitch assembly with the insert ring in the first position; 
           [0014]      FIG. 4  is a top view of the trailer hitch assembly with the insert ring in the second position; 
           [0015]      FIG. 5  is a front view of the trailer hitch assembly in the drop configuration; 
           [0016]      FIG. 6  is a side view of the trailer hitch assembly in its lowest gusset down drop configuration; 
           [0017]      FIG. 7  is a side view of the trailer hitch assembly in its highest gusset down drop configuration; 
           [0018]      FIG. 8  is a side view of the trailer hitch assembly in its lowest gusset up drop configuration; 
           [0019]      FIG. 9  is a side view of the trailer hitch assembly in its highest gusset up drop configuration; 
           [0020]      FIG. 10  is a side view of the trailer hitch assembly in its highest gusset up rise configuration; 
           [0021]      FIG. 11  is a side view of the trailer hitch assembly in its lowest gusset up rise configuration; 
           [0022]      FIG. 12  is a side view of the trailer hitch assembly in its highest gusset down rise configuration; 
           [0023]      FIG. 13  is a side view of the trailer hitch assembly in its lowest gusset down rise configuration; 
           [0024]      FIG. 14  is a bottom view of the coupling base; 
           [0025]      FIG. 15  is a side view of the coupling base; 
           [0026]      FIG. 16  is a front view of the coupling base; 
           [0027]      FIG. 17  is a top view of the support member with the gusset plate up; 
           [0028]      FIG. 18  is a side view of the support member with the gusset plate down; 
           [0029]      FIG. 19  is a front view of the support member with the gusset plate down; 
           [0030]      FIG. 20  is a top view of the ball mount member; 
           [0031]      FIG. 21  is a side view of the ball mount member; 
           [0032]      FIG. 22  is a front view of the ball mount member; 
           [0033]      FIG. 23  is a top view of the insert ring; 
           [0034]      FIG. 24  is a side view of the insert ring; and 
           [0035]      FIG. 25  is an end view of the insert ring. 
       
    
    
     DETAILED DESCRIPTION 
       [0036]    There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. 
         [0037]    In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting. 
         [0038]    Looking at  FIGS. 1 and 2  the general arrangement of all the components of the present invention may best be seen. The class IV trailer hitch assembly  2  has four major components: the support member  4 ; the ball mount member  6 ; the coupling base  8  and the hitch ball assembly  10 . 
         [0039]    Looking at  FIGS. 17-19  it can be seen that the support member  4  is a hollow square support tube  12  welded perpendicularly to the outside of the closed side of the U shaped connection bracket  14  with a generally triangular strengthening gusset plate  16  welded on one of its edges along the linear axis of the support tube  12  and welded on its adjacent edge to the linear axis of the connection bracket  14 . There are two sets of hitch pin orifices  18  formed through parallel sides of the support tube  12  to accommodate the passage of a hitch pin that couples the trailer hitch assembly to the receiver on the tow vehicle as is well known in the art. The two sets of hitch pin orifices  18  are situated along the length of the support tube at 3.5 inches and 4.75 inches from the inserted end such that approximately 6.75 to 7.0 inches of the support tube  12  extends beyond the centerline of the hitch pin and approximately only 4.5 to 3.25 inches reside outside of the receiver. This allows some adjustment of the trailer hitch  2  away from the tow vehicle&#39;s bumper yet not enough to enable greater than a 5 degree inelastic deformation of the trailer hitch assembly  2  as measured from the original position of the hitch ball axis when the SAE J684 and V-5 test loads are applied. The U shaped connection bracket  14  is dimensionally sized to accommodate the drop tube  22  of the ball mount member  6 . There are two sets of bolt orifices formed through the parallel sides of the connection bracket. These bolt orifices  20  are spaced apart at intervals identical to the drop tube height adjustment orifices  26 . In the preferred embodiment this is a two inch spacing. 
         [0040]    Looking at  FIGS. 20-22  the ball mount member  6  can be seen made up of a hollow square drop tube  22  welded in a perpendicular configuration to a mounting base plate  24  that has a hitch receiving orifice  25  formed there through. There are four pairs of height adjustment orifices  26  formed through parallel side walls of the square tubing that the drop tube is formed from. These height adjustment orifices  26  are spaced for precise alignment with the bolt orifices  20  such that any adjacent two height adjustment orifices  26  of the five can be used for the passage of a pair of bolts  40  washers  42  and nuts  44  to connect the support member  4  to the ball mount member  6 . In the preferred embodiment these are Grade 8, ⅝ inch bolts  40  with ⅝ inch washers  42  and ⅝ inch nuts  44 . 
         [0041]    Looking at  FIGS. 14-16  it can be seen that the coupling base  8  has a coupling plate  28  with an Isosceles trapezoidal configuration and that has a raised peripheral flange  30  extending normally therefrom along three of the base plate&#39;s edges. The edges on two of the non parallel sides and the shorter contained side have this peripheral flange  30 . An oval adjustment ring cutout  32  extends through the center of coupling plate  28  and is flanked on either side by a set of two parallel stabilization bars  34  that extend normally from the bottom side of the coupling plate  28 . The coupling plate  28  rests directly atop mounting base plate  24  such that each of their longitudinal axis reside in the same plane. The stabilization bars  34  are spaced so as to allow the mounting base plate  24  to fit snugly between them when the coupling plate  28  is rested directly atop mounting base plate  24 . This maintains the alignment of the longitudinal axes of these two plates despite any jarring forces either may encounter when the trailer and tow vehicle are being coupled. The stabilization bars  34  are keyways that are welded into laser cut matingly conformed cutouts in the coupling plate  28 . Into the adjustment ring cutout  32  is placed the adjustment ring  36 . This is the oval ring that was laser cut from the coupling plate  28  to form the cutout  32 . (See  FIGS. 23 - 25 .) Into the adjustment ring  36  is cut a hitch ball orifice  38 . This hitch ball orifice  38  is alignable with the hitch receiving orifice in the base plate. This hitch ball orifice  38  is not cut in the geometric center of the adjustment ring  36  but rather is cut centered about the longitudinal axis of the adjustment ring  36  but not centered about the axial axis of the adjustment ring  36 . In this way the adjustment ring may be placed in the coupling plate  28  and reside on the mounting base plate  24  so as to accommodate two different positions of the hitch ball orifice  38 . These two positions place the hitch ball at different distances from the raised peripheral flange  30  to accommodate the different coupling heads on the different trailers. In the preferred embodiment the adjustment ring  36  is four inches long and ¼ inch thick with a 1 or 1.25 inch hitch ball orifice  38 . 
         [0042]    Looking at  FIGS. 3 and 4  the adjustment ring  36  can be seen in the first position ( FIG. 3 ) and second position ( FIG. 4 ) in the coupling plate  28 . In the first position it can be seen that the hitch ball  46 , when installed as in  FIG. 5  resides further away from the raised peripheral flange  30  of the coupling plate  28  to accommodate the coupling of larger hitch couplers. When any of the commercially available coupler guides is affixed to the coupling plate  28  there must be enough room to allow the trailer coupler to contact the inner face of the guide and then be lowered onto the hitch ball  46 . Notably, it is this same contact during coupling that could cause the lateral movement of the coupling plate  28  and the resultant hitch/coupler misalignment if it were not for the stabilizer bars  30 . 
         [0043]    It is to be noted that generally conventional trailer hitches utilize only one weld that connects the support member and the ball mount member. Since these conventional hitches are not adjustable, the ball mount member is simply a plate bent gradually to 90 degrees with a hitch ball orifice there through. Although these conventional hitches may be rotated 180 degrees to give both a drop and a rise in height with respect to the horizontal centerline of the receiver, because of the radius of the bend in the ball mount member a coupling plate  28  cannot reside flat and thus cannot be utilized with a coupling guide to couple the tow vehicle to the trailer. It is for this reason that the ball mount member  6  of the adjustable trailer hitch  2  utilizes a two piece welded construction at the square drop tube  22  to mounting base plate  24  interface that has its included angle set to 90 degrees. In this manner a coupling plate  28  may be used whether the ball mount member  6  is in the drop or rise configuration. 
         [0044]    Looking at  FIG. 2  the hitch ball assembly  10  can be seen to comprise the hitch ball  46 , hitch ball washer  48  and hitch ball nut  50  as is commonly known in the industry. In the preferred embodiment this is a 2¼ inch standard sized hitch ball assembly as is required for a class IV load. This necessitates a 2 5/16 inch diameter hitch ball orifice  38 . 
         [0045]    In the preferred embodiment and to meet the SAE J684 (Rev 2005) V5 testing of the allowable deformation of the trailer hitch  2  in both the gusset up maximum rise configuration and the gusset down maximum drop configuration the support tube  12  and drop tube  18  is made of ASTM A500 cold formed grade B 2 inch square structural tubing and the remainder of the trailer hitch assembly is made of ASTM A36HR HR steel. The connection bracket  14  is ⅜ inch thick with a 2 inch internal U spacing, the gusset plate  18  is ¼ inch thick and approximately 2 inches by 2.5 inches along adjacent edges. The mounting base plate  24  is approximately one inch thick. The relevant dimensions of the hitch assembly without the coupling base  8  are as follows:
   support tube  12 —overall length 10.3 inches, ASTM A500 cold formed Grade B steel ¼ inch thick, two inch nominal square tubing;   hitch pin orifices  18 —two in total, centered on longitudinal axis, to accommodate a ⅝ inch diameter hitch pin, 1¼ inches between centers, first orifice 3½ inches from receiver insert end;   connection bracket  14 —⅜ inch thick 2 inch I.D. ASTM A36HR HR steel U shaped channel, overall length 4.9 inches, two inch square;   bolt orifices  20 —two in total, centered on the longitudinal axis and along the longitudinal length, spaced 2 inches apart on centers, to accommodate ⅝ inch diameter bolts,   gusset plate  16 —2 inches by 2½ inches generally triangular shape, ¼ inch thick ASTM A36HR HR steel;   drop tube  22 —overall length of 10.2 inches, ASTM A500 cold formed Grade B steel ¼ inch thick, two inch square tubing;   height adjustment orifices  26 —five in total, centered along the longitudinal centerline, 2 inches between centers;   base plate  24 —1 inch thick ASTM A36HR HR steel, 2½ inches wide by 7¼ inches long, producing a 5 inch platform for the hitch ball or a coupling plate; and   hitch receiving orifice  25 —two common sizes to accommodate a 1 inch or 1.25 inch hitch ball shank   
 
         [0055]    The resultant adjustable hitch has an 8.85 inch drop or a 7.65 inch rise and a 12.8 inch extension from the center of the hitch pin orifice (in the most extended position) to the center of the hitch receiving orifice taken from the top surface of the base plate. 
         [0056]    The present design allows for 12 vertical adjustments of the hitch ball assembly  10  over a range of 16 inches, 8½ inches above the longitudinal centerline of the support tube  12  and 7½ inches above the longitudinal centerline of the support tube  12 . There are four different combinations of the support member  4  and the ball mount member  6  as either can be rotated 180 degrees and then connected. When taken in combination with the two different horizontal adjustments of the support member  4  there is a total of 24 different positions. Simply stated, the support member  4  may be reversed within the receiver on the tow vehicle and the ball mount member  6  may be reversed within the connection bracket of the support member  4  and the resulting assemblies will still exceed the testing requirements set forth herein for a Class IV trailer hitch. 
         [0057]    Looking at  FIGS. 6-13  the various combinations can be seen, as explained in the following chart. Which height adjustment orifices used (1 &amp; 3, 2 &amp; 4, or 3 &amp; 5 from top to bottom of the drop tube  22  respective of the top tube orientation) are indicated in the chart along with the drop or rise of the top of the base plate. Since the base plate  24  is flat the coupling plate  28  may be mounted on either side of it. 
         [0058]      FIGS. 6 &amp; 7  show the support tube  12  with the gusset  16  down and the drop tube in the drop configuration with the base plate  24  on the bottom.  FIG. 6  uses the 1 &amp; 3 height adjustment orifices  26  while  FIG. 7  uses the 3 &amp; 5 height adjustment orifices. These represent the extremes of adjustment in this configuration as indicated by their respective distances (a and b) from the X plane. 
         [0059]      FIGS. 8 &amp; 9  show the support tube  12  with the gusset  16  up and the drop tube in the drop configuration with the base plate  24  on the bottom.  FIG. 8  uses the 1 &amp; 3 height adjustment orifices  26  while  FIG. 9  uses the 3 &amp; 5 height adjustment orifices. These represent the extremes of adjustment in this configuration as indicated by their respective distances (c and d) from the X plane. 
         [0060]      FIGS. 10 &amp; 11  show the support tube  12  with the gusset  16  up and the drop tube in the rise configuration with the base plate  24  on the top.  FIG. 10  uses the 1 &amp; 3 height adjustment orifices  26  while  FIG. 11  uses the 3 &amp; 5 height adjustment orifices. These represent the extremes of adjustment in this configuration as indicated by their respective distances (e and f) from the X plane. 
         [0061]      FIGS. 12 &amp; 13  show the support tube  12  with the gusset  16  down and the drop tube in the rise configuration with the base plate  24  on the bottom.  FIG. 12  uses the 1 &amp; 3 height adjustment orifices  26  while  FIG. 13  uses the 3 &amp; 5 height adjustment orifices. These represent the extremes of adjustment in this configuration as indicated by their respective distances (g and h) from the X plane. 
         [0000]    
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                   
               
               
                 Support Member 
                 Ball Mount Member 
                 Drop from 
                 Rise from 
               
             
          
           
               
                 Gusset 
                 Gusset 
                 Bottom 
                 Top Base 
                 Support 
                 Support 
               
               
                 Down 
                 Up 
                 Base Plate 
                 Plate 
                 Tube Center 
                 Tube Center 
               
               
                   
               
             
          
           
               
                 x 
                   
                 1 &amp; 3 
                   
                 4.5 
                 in 
                   
               
               
                 x 
                   
                 2 &amp; 4 
                   
                 6 
                 in 
               
               
                 x 
                   
                 3 &amp; 5 
                   
                 7.5 
                 in 
               
             
          
           
               
                   
                 x 
                   
                 1 &amp; 3 
                   
                 5.5 
                 in 
               
               
                   
                 x 
                   
                 2 &amp; 4 
                   
                 4 
                 in 
               
               
                   
                 x 
                   
                 3 &amp; 5 
                   
                 2.5 
                 in 
               
             
          
           
               
                 x 
                   
                 1 &amp; 3 
                   
                 3 
                 in 
                   
               
               
                 x 
                   
                 2 &amp; 4 
                   
                 4.50 
                 in 
               
               
                 x 
                   
                 3 &amp; 5 
                   
                 6 
                 in 
               
             
          
           
               
                   
                 x 
                   
                 1 &amp; 3 
                   
                 5.5 
                 in 
               
               
                   
                 x 
                   
                 2 &amp; 4 
                   
                 7 
                 in 
               
               
                   
                 x 
                   
                 3 &amp; 5 
                   
                 8.5 
                 in 
               
               
                   
                   
               
             
          
         
       
     
         [0062]    The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. There are numerous variations and modifications thereof that will also remain readily apparent to others skilled in the art, now that the general principles of the present invention have been disclosed. As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. For example, it is known that the geometric configuration and dimensions and specified materials of the preferred embodiment of the present invention will pass the SAE testing requirements for a Class IV hitch, although it is known that modifications of these would allow for a higher or lower rating of hitch. All dimensions given herein may vary with a dimensional tolerance of 5% and the adjustable hitch assembly will still be capable of meeting the Class IV trailer hitch SAE J684 (Rev 2005) and V-5 test requirements.