Patent Publication Number: US-2023139691-A1

Title: Trailer Coupler Riser

Description:
BACKGROUND 
     This invention relates generally to hitch assemblies for coupling a trailer to a towing vehicle. More specifically, the invention relates to a removable adapter for a channel mount trailer coupler that enables a user to couple the trailer to a towing vehicle regardless of the relative heights of the trailer and the towing vehicle. 
     Automobiles, trucks and other vehicles are regularly equipped for towing trailers. In doing so, it is important that the trailer be level, rather than at an angle with respect to the towing vehicle, regardless of the relative heights of the towing vehicle and the trailer. Previously, for towing vehicles that have a high ground clearance, such as “lifted” trucks, this level connection has been achieved by using a using a ball mount with a relatively large drop such that the hitch ball is disposed well below the draw bar of the of the ball mount and the receiver tube mounted on the vehicle frame. This solution effectively brings the ball mount down to the level of the trailer coupler. For heavy-duty towing, such as towing commercial trailers, this solution presents a number of drawbacks. The moment arm associated with the dropped ball mount creates an extra load on the ball mount and hitch system, which reduces the towing capacity for the hitch components in comparison to a straight ball mount without a drop. To address this issue, dropped ball mounts must be significantly reinforced, and consequently are significantly more expensive than straight ball mounts. For heavier commercial trailers, such dropped ball mounts may not have an adequate tow rating. 
     It is an object of the present invention to provide a trailer coupling device with which a towed vehicle, such as a trailer, can effectively and safely be connected to a towing vehicle regardless of the relative heights of the trailer and the towing vehicle. 
     It is still another object of the present invention to provide such an apparatus that can be used to tow heavy trailers, such as commercial trailers, and that can be used with relatively high towing vehicles, including “lifted” trucks. 
     It is another object of the invention to provide an apparatus that can readily be used to couple a trailer to a tall towing vehicle so that there is a more direct horizontal (or “neutral”) drawbar pull, which reduces the load on the ball mount and hitch system. 
     It is yet another object of the present invention to provide an apparatus that can be easily removed when not needed, such as when coupling the trailer to a standard-height tow vehicle. 
     It is another object of the present invention to provide such an apparatus that is relatively easy to manufacture and to use. 
     Additional objects and advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations pointed out in the appended claims. 
     SUMMARY 
     To achieve the foregoing objects, and in accordance with the purposes of the invention as embodied and broadly described in this document, there is provided an adapter for a trailer coupler assembly of a vehicle to be towed. The adapter includes an elongated riser member configured to be removably mounted to a vertical channel of a trailer coupler assembly. The riser member has a transverse cross-section generally in the shape of an I-beam having a first channel portion and an opposing second channel portion. The first channel portion includes a generally U-shaped transverse cross-section and is configured to be removably mounted to a vertical channel of a trailer coupler assembly at one of a plurality of longitudinal positions along a length of the vertical channel of the trailer coupler assembly. The opposing second channel portion includes a generally U-shaped transverse cross-section configured to hold a trailer coupler. 
     In some embodiments, the first channel portion includes two opposing first channel side walls and a first channel inner wall, and the first channel portion defines a first channel opening facing outward from the first channel inner wall. In some embodiments, the second channel portion includes two opposing second channel side walls and a second channel inner wall, and the second channel portion defines a second channel opening facing outward from the second channel inner wall. 
     In some embodiments, the transverse cross-section of the first channel portion is disposed about a first channel center line, the transverse cross-section of the second channel portion is disposed about a second channel center line, and the first channel center line and the second channel center line are offset from each other. In some embodiments, the first channel portion includes two opposing first channel sidewalls, each of which includes a plurality of transverse holes spaced longitudinally along the length of the first channel portion, and each of the plurality of transverse holes in one of the first channel sidewalls is transversely registered with one of the plurality of transverse holes in the opposing first channel sidewall. In some embodiments, each of the first riser channel portion and the second riser channel portion has a width corresponding to the width of the vertical channel of the trailer coupler assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate the presently preferred embodiments of the invention and, together with the general description given above and the detailed description of the preferred methods and embodiments given below, serve to explain the principles of the invention. 
         FIG.  1    is a side perspective view of a towing vehicle with a dropped hitch ball mount and a trailer with a prior art vertical channel coupler assembly that includes a ball and socket coupler mounted to vertical channel on the trailer tounge. 
         FIG.  2    is a side elevation view of the tow hitch assembly of  FIG.  1    wherein the trailer coupler assembly has been modified by adding a channel riser according to the present invention. 
         FIG.  3    is a top perspective view of the channel riser of  FIG.  2   . 
         FIG.  4    is another perspective view of the channel riser of  FIG.  2    showing the centerlines of the first and second riser channel portions offset from each other. 
         FIG.  5    is a top plan view showing the channel riser of  FIG.  2    positioned within the vertical channel of a trailer coupler assembly so that the riser can be mounted to the vertical channel. 
         FIG.  6    is a perspective view of another embodiment of the channel riser according to the present invention, wherein the sidewalls of the second riser channel portion have cutouts. 
         FIG.  7    is a perspective view of yet another embodiment of the channel riser according to the present invention, wherein the centerlines of both the first and second riser channel portions are aligned with each other. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in more detail to presently preferred embodiments of the invention, as illustrated in the accompanying drawings. While the invention is described more fully with reference to these examples and drawings, the invention in its broader aspects is not limited to the specific details, representative devices, and illustrative examples shown and described. Rather, the description that follows is to be understood as a broad, teaching disclosure directed to persons of ordinary skill in the appropriate arts, and not as limiting upon the invention. 
     It will be appreciated that terms such as “forward,” “rearward,” “upper,” “inner,” “outer,” “vertical,” “horizontal,” “bottom,” “below,” “top,” “side,” “inwardly,” “outwardly,” “downwardly” and “lower” and other positional descriptive terms used in this specification are used merely for ease of description and refer to the orientation of the referenced components as shown in the figures. It should be understood that any orientation of the components described herein is within the scope of the present invention. 
     For purposes of explanation, and to further assist in the understanding of this invention, a brief description of the operation of a standard previously-known tow hitch assembly that includes a vertical channel trailer coupler assembly follows. Such couplers are used for relatively high weight capacity towing, such as for construction, cargo and livestock trailer applications.  FIG.  1    illustrates one embodiment of such a standard channel mount trailer coupler assembly  10 , which utilizes a vertical, U-shaped channel  18  with the open side of the channel facing forward for hitching a trailer  4  (or other vehicle to be towed) to a towing vehicle  2  (such as a truck or sport utility vehicle). The channel mount coupler assembly  10  includes a coupler  20  mounted to the vertical channel  18 , which in turn is mounted to the trailer tongue  6  to form an integrated frame unit. The vertical channel  18  has two opposing side walls  30 ,  30 ′ and a forward facing channel opening  19  for receiving the coupler  20 . Each of the vertical channel side walls  30 ,  30 ′ has a series of transverse holes  31 ,  31 ′ that are suitably spaced at vertical intervals, and are horizontally registered with the holes on the opposing side wall  30 ′,  30 , to receive pins or bolts  32  by which the coupler  20  can be secured to the vertical channel  18  at different heights. 
     Still referring to  FIG.  1   , the coupler  20  has a coupler body  22  with a ball-shaped coupler socket  24  that has a bottom coupler socket opening  23 , which allows the insertion of a hitch ball  34  into the coupler socket  24  to hitch the trailer  4  to the towing vehicle  2 . The hitch ball  34  is commonly affixed to the rear end of the tow vehicle  2  utilizing a hitch ball assembly  12  that can support the tongue weight of the trailer  4 . To couple the trailer  4  to the towing vehicle  2 , the trailer tongue  6  is raised above the hitch ball  34 —such as by using a trailer jack  8 —so that the coupler socket  24  can be lowered from an elevated height onto the hitch ball  34 . As the coupler socket  24  is lowered, the hitch ball  34  advances into the coupler socket  24  through the coupler socket opening  23  until it seats within the coupler socket  24 . Typically, such couplers incorporate a retaining mechanism for securing the hitch ball  34  in a retention or coupled position within the coupler socket  24 . The retaining mechanism commonly includes a latching mechanism. When properly set in a closed position, the latching mechanism provides a retaining force between the hitch ball  34  and coupler socket  24 , thereby securing the trailer  4  to the towing vehicle  2 . One type of such a ball-and-socket coupler is a self-latching coupler, which automatically latches when the trailer coupler is lowered onto the hitch ball. An example of such a self-latching coupler is the EZ Latch coupler marketed by Demco Manufacturing Co. of Boyden, Iowa. 
     Still referring to  FIG.  1   , the hitch ball assembly  12  includes a hitch ball mount  28  that is generally L-shaped and has a generally vertical leg  26  and a generally horizontal leg  27 . The hitch ball mount  28  is supported by a draw bar  14  that is sized and shaped to closely fit within a receiver  16  mounted to the towing vehicle  2 . The hitch ball mount  28  is considered a dropped hitch ball mount because the ball  34  is lower than the top of the hitch receiver  16 . The hitch ball  34  has a threaded shank  36  that is removably mounted to the hitch ball mount horizontal leg  27  with a hitch ball nut  37 . Because the hitch ball  34  is removable, hitch balls of various sizes (e.g.,  2 ″, 2 ⅚″ or another size) can be used. As is known in the art, the draw bar  14  has side holes (not shown) for receiving a lateral hitch pin  15 . When the draw bar  14  is inserted into the receiver  16 , it can be longitudinally positioned so that the draw bar side holes align with corresponding receiver side holes  17 . Once aligned, the hitch pin  15  can be inserted through the draw bar side holes (not shown) and the aligned receiver side holes  17  to prevent the draw bar  14  from moving longitudinally within the receiver  16 . The hitch pin can be held in place by a hitch pin clip (not shown), as is known in the art, to prevent lateral forces from removing the hitch pin  15  from the side holes  17 . 
     Having described a known vertical channel trailer coupler assembly, the features of an adapter according to the present invention will now be described. The adapter includes a channel riser (or vertical extension member) that can be mounted to a standard-size vertical channel trailer coupler as shown in  FIG.  2    below. 
       FIG.  2    illustrates one embodiment of a channel riser  40  according to the present invention shown mounted to a vertical channel trailer coupler  10  of the type shown in  FIG.  1   . The riser  40  allows the coupler  20  to be mounted at a selected height above the top of the forward-facing vertical channel  18 . This feature enables a user to couple the trailer  4  to a tall tow vehicle  2  (such as one that has been modified with a lift kit or oversized tires) using a standard straight hitch on the tall tow vehicle rather than using a drop hitch, which is more expensive and has reduced towing capacity compared to the straight hitch. The riser  40  can be removed from the vertical channel  18 . Thus, if the user does not need the riser&#39;s extended height (such as for a towing application involving a tow vehicle of a standard height) and the user does not want to navigate climbing over or around the riser  40  when coupling the trailer to the standard-height tow vehicle, the user can simply remove the riser  40 . 
     Referring to  FIGS.  2 - 5   , the channel riser  40  has the general shape of an I-beam that defines two opposing channel portions  42   a ,  42   b , each of which has a general U-shape in transverse section. Channel portion  42   a  is formed by two opposing riser channel sidewalls  43   a ,  43   a ′, and a riser inner wall  46   a  with a channel opening  44   a  facing outward from the inner wall  46   a . Similarly, channel portion  42   b  is formed by two opposing riser channel side walls  43   b ,  43   b ′ and a riser inner wall  46   b  with a channel opening  44   b  facing outward from the inner wall  46   b . Each of the riser channel portions  42   a ,  42   b  has an outer width Wo that corresponds to the outer width of the vertical channel  18  and an inner width Wi that corresponds to the width Wi of the vertical channel opening  19  (i.e., the interior of the vertical channel  18 ) The inner width Wi is a standard dimension in the trailer industry suitable for receiving standard industry couplers so that such couplers can be used interchangeably. As shown in  FIGS.  4  and  5   , the centerlines Ca-Ca, Cb-Cb of channel portions  42   a ,  42   b  are offset from each other by a distance D, which corresponds to the width of each of the sidewalls  30 ,  30 ′ of the vertical channel  18  as well as the width of the riser channel sidewalls  43   a ,  43   a ′ (see  FIG.  5   ). By using an I-beam structure, the channel riser  40  can be fabricated so that its bending strength surpasses that of the trailer tongue  6 . By offsetting the riser channel portions  42   a ,  42   b  from each other as described above, the channel riser  40  can be mounted to the vertical channel  18  so that the centerline C-C of the vertical channel  18  (see  FIG.  5   ) aligns with the centerline of the coupler  20  when it is mounted to the channel riser  40 . 
     Still referring to  FIGS.  2 - 5   , the side wall  43   a  of riser channel portion  42   a  has a series of transverse holes  45   a  that are suitably spaced at vertical intervals, and are horizontally registered with the transverse holes  45   a ′ on the opposing side wall  43   a ′ to receive pins or bolts  32  by which the riser  40  can be removably secured within the vertical channel  18  or by which the coupler body  20  can be removably secured to the riser  40  within the riser channel portion  42   a . The tranverse holes  45   a ,  45   a ′ can be vertically spaced at intervals that correspond with the vertical spacing of the transverse holes  31 ,  31 ′ in the vertical channel  18 , or the vertical spacing of the transverse holes  45   a ,  45   a ′ can be different than the spacing intervals of the transverse holes  31 ,  31 ′ and at different distances from one another for attainment of various positions of adjustment between the riser  40  and the vertical channel  18 . To secure riser channel portion  42   a  in the vertical channel  18 , at least one pair of the holes  45   a ,  45   a ′ are to be mated or brought into register with a selected pair (or pairs) of holes  31 ,  31 ′ in the vertical channel  18  after which a bolt or pin  32  (see  FIG.  2   ) can be passed through the registering holes to secure the vertical channel  18  and the riser  40  in their assembled relationship. In this configuration, when the riser channel portion  42   a  is used to secure the riser  40  in the vertical channel  18 , the mounting position of the riser  40  relative to the vertical channel  18  can be adjusted longitudinally without difficulty. 
     Similarly, the side wall  43   b  of the riser channel portion  42   b  has a series of transverse holes  45   b  that are suitably spaced at vertical intervals, and are horizontally registered with transverse holes  45   b ′ on the opposing side wall  43   b ′ to receive pins or bolts  32  by which the riser  40  can be removably secured within the vertical channel  18  or by which the coupler body  20  can be removably secured to the riser  40  within the riser channel portion  42   b . The tranverse holes  45   b ,  45   b ′ can be vertically spaced at intervals (as described above for transverse holes  45   a ,  45   a ′ of side wall  43   a ) to attain various positions of adjustment between the riser  40  and the vertical channel  18 . In this configuration, when the riser channel portion  42   b  is used to secure the riser  40  in the vertical channel  18 , the mounting position of the riser  40  relative to the vertical channel  18  can be adjusted longitudinally without difficulty. 
     As discussed above, each of the riser channel portions  42   a ,  42   b  has an outer width Wo, which corresponds to the outer width Wo of the vertical channel  18  and an inner width Wi that corresponds to the inner width Wi of the vertical channel  18 . As shown in  FIG.  5   , in this configuration, the riser  40  can be mounted to the vertical channel  18  by positioning the side wall  43   a  of the riser channel portion  42   a  outside the sidewall  30  of the vertical channel  18  and the opposing side wall  43   a ′ of the riser channel portion  42   a  inside the corresponding opposite sidewall  30 ′ of vertical channel  18 . When assembled in this way, riser channel portion  42   b  will then face forward toward the tow vehicle  2  and the coupler  20  can be secured within riser channel portion  42   b  in the manner described above. Alternatively, the riser  40  can be mounted to the vertical channel  18  by positioning the side wall  43   b ′ of the riser channel portion  42   b  outside the sidewall  30  of the vertical channel  18  and the opposing side wall  43   b  of the riser channel portion  42   b  inside the corresponding opposite sidewall  30 ′ of vertical channel  18 . When assembled in this way, riser channel portion  42   a  will then face forward toward the tow vehicle  2  and the coupler  20  can be secured within riser channel portion  42   a  in the manner described above. 
     Referring to  FIG.  6   , another embodiment of the channel riser  40  is shown. In this embodiment, the structure and dimensions of the channel riser  40  are similar to that of the embodiment shown in  FIGS.  2 - 5   , except that the riser channel side walls  43   a ,  43   a ′ of riser channel portion  42   a  do not extend along the full length of the riser inner wall  46   a . Rather, each of the sidewalls  43   b ,  43   b ′ of the forward-facing riser channel  42   b  has a cutout  50 ,  50 ′ (i.e., voids) to reduce the overall weight of the channel riser  40 . A flange or rib  52 ,  52 ′ extends along the length of each side of the riser inner wall  46   a  to provide rigidity to the channel riser  40 . 
     Referring to  FIG.  7   , in another embodiment of the channel riser  40 , each of the two opposing channel portions  42   a ,  42   b  have different widths and are disposed on a single centerline C-C, which can be in line with the centerline of the trailer  4 . The forward-facing riser channel portion  42   b  has an outer width Wo corresponding to the outer width Wo of the vertical channel  18  and an inner width Wi corresponding to the inner width Wi of the vertical channel  18 , as previously described. The rearward-facing riser channel  42   a  has a width We the corresponds to the width of the coupler body  22  and is slightly smaller than the inner width Wi of the vertical channel  18  (see  FIG.  5   ) so that the reward facing riser channel  42   a  can be closely received within the vertical channel  18 . In this configuration, the rearward-facing riser channel  42   a  also includes transverse holes  45   a  as previously described to receive pins or bolts  32  by which the riser channel portion  42   a  can be removably secured within the vertical channel  18 . 
     In some embodiments of the channel riser  40 , the channel portions  42   a ,  42   b  are made of steel with the holes drilled or punched and the channel riser  40  is fabricated by welding the two channel portions  42   a ,  42   b  together, although it will be understood that other suitable metal and methods of manufacture may be chosen. 
     Having read this disclosure, it will be understood by those having skill in the art that the trailer coupler adapter of the present invention provides a number of advantages over the prior art. It can be used to effectively and safely connect a trailer or other towed vehicle to a towing vehicle regardless of the relative heights of the towed vehicle and the towing vehicle and without having to use an expensive dropped ball mount. It is relatively inexpensive to manufacture and easy to use. It can be used to couple commercial trailers to relatively tall towing vehicles, including “lifted” trucks. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative devices, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the general inventive concept.