Patent Document

CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Provisional Patent Application Ser. No. 61/081,957 entitled “Adjustable Trailer Lunette”, filed on Jul. 18, 2008, the entire disclosure of which is incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed toward hitches and other connection apparatus for use on equipment such as trailers and, more particularly, toward a trailer hitch assembly which provides for hitch adjustability in the vertical, lateral and fore/aft directions allowing for quick and efficient connection to a tow vehicle in a variety of rough and uneven terrains. 
     BACKGROUND OF THE INVENTION 
     Trailers and hitches are well-known in the prior art. Trailers may be utilized to haul various types of vehicles, equipment and cargo. Trailers may take virtually any configuration depending upon the type of vehicle, equipment, cargo, etc. they are designed to transport. A hitch assembly and an element for connection to a vehicle are typically attached to the trailer for connection to a tow vehicle. A lunette ring is a type of trailer hitch that works in connection with a pintle hook on the tow vehicle. Another type of trailer hitch is a tow-hall type hitch which utilizes a tow-ball attached to the vehicle which engages a tongue on the trailer. 
     Typical trailers will include a frame for supporting the item(s) to be transported and a chassis supporting the frame. An axle is provided beneath the chassis for wheels which contact a road surface. A hitch assembly including a vehicle connection element (lunette ring, tongue, etc) is provided at the head of the trailer frame for connection to a vehicle. Trailers also typically have a jack connected to the frame to support the hitch assembly during hitching and unhitching to a vehicle. 
     When attaching a trailer to a tow vehicle, a problem that often arises is that the tow vehicle cannot be placed close enough to the trailer to allow connection of the trailer to the tow vehicle. Such a problem often arises in uneven and/or rough terrain where optimal placement of the tow vehicle with respect to the trailer simply cannot be accomplished. If the trailer is supporting a heavy load that cannot be moved manually, trailer hook up to the tow vehicle can become very time consuming and burdensome, and in certain instances may simply not be possible. 
     Additionally, and as can be appreciated, in a military environment it is often imperative to provide quick and efficient hook up of a trailer to a tow vehicle. In a hostile environment, the longer such a connection process takes and the more individuals who are required to effectuate it, the more dangerous the situation can become. 
     The present invention is directed toward overcoming one or more of the above-mentioned problems. 
     SUMMARY OF THE INVENTION 
     The adjustable trailer hitch assembly of the present invention is designed for attachment to the head of most commercially available trailers. The inventive adjustable trailer assembly includes a first weldment member pivotally attachable to a head of a trailer, and a second weldment member operably connected to the first weldment member for lateral movement between extended and locked positions. Collapsible extension arms operably connect the first and second weldment members providing movement between the extended and locked positions. The collapsible extension arms are positionable between a first collapsed position with the first and second weldment members adjacent one another defining the locked position, and a second extended position with the first and second weldment members separated from one another defining the extended position. A vehicle connection element is operably connected to the second member, with the vehicle connection element moveable along a vertical length of the second member for connection to a tow vehicle. 
     In one form, the vehicle connection element includes a lunette ring attachable to a pintle hook on a tow vehicle. 
     In another form, the first weldment, the second weldment member, the vehicle connection element and the collapsible extension arms are made of high strength steel. 
     Locking pins are provided on the first weldment member for both locking the trailer hitch assembly in a center-aligned position securing it from pivoting, and also to lock the second weldment member in a locked position. The locking pins are spring biased and actuatable by a user for disengagement to allow the trailer hitch assembly to pivot and the second weldment member to extend simultaneously. Such a design provides hitch adjustability in the vertical, lateral and fore/aft directions that has previously not been obtainable with prior art designs. 
     Some advantages of the inventive adjustable trailer hitch assembly include, but are not limited to:
         Rotating pins and bushings are less susceptible to freeze-ups from dirt and debris enabling the assembly to have an extended service life.   Lateral movement of the assembly can occur without requiring extension.   The assembly can be integrated by welding to trailer chassis, which allows designers to easily incorporate the assembly into their designs.   The inventive assembly will not catastrophically fail while extended should the locking pin operation not be executed.   The inventive assembly auto-latches into the tow position.   The inventive assembly is scalable to meet various trailer sizes and specifications.   Lunette rings, ball hitches and other types of vehicle connection elements may be used with the inventive adjustable trailer hitch assembly.       

     It is an object of the present invention to provide an adjustable trailer hitch assembly capable of adjustability in the vertical, lateral and fore/aft directions allowing for quick and efficient connection to a tow vehicle in a variety of rough and uneven terrains. As long as the driver of the tow vehicle gets the tow connection element on the vehicle within a certain minimum distance of the corresponding tow connection element on the hitch assembly, the inventive assembly permits quick and easy hook-up to the tow vehicle. 
     It is a further object of the present invention to provide an adjustable trailer hitch assembly which provides failsafe operation in the event the locking pins do not engage. 
     It is yet a further object of the present invention to provide an adjustable trailer hitch assembly that can be easily integrated into a variety of types of trailers, including, tactical military trailers, commercial and residential hauling trailers, military and commercial boat trailers, farm implements, etc. 
     Other objects, aspects and advantages of the present invention can be obtained from a study of the specification, the drawings, and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of the of the inventive adjustable trailer hitch assembly connected to a trailer, with the inventive assembly in a locked position; 
         FIG. 2  is a perspective view of the of the inventive adjustable trailer hitch assembly connected to a trailer, with the inventive assembly in an extended position; 
         FIG. 3  is a top view of the of the inventive adjustable trailer hitch assembly connected to a trailer, with the inventive assembly in a pivoted and locked position; 
         FIG. 4  is a top view of the of the inventive adjustable trailer hitch assembly connected to a trailer, with the inventive assembly in a pivoted and locked position; 
         FIG. 5  is a perspective view of a first weldment member of the inventive adjustable trailer hitch assembly; 
         FIG. 6  is a perspective view of a second weldment member of the inventive adjustable trailer hitch assembly; 
         FIGS. 7   a - b  are top and front views, respectively, of a first extension arm of the inventive adjustable trailer hitch assembly; 
         FIGS. 8   a - b  are top and front views, respectively, of a second extension arm of the inventive adjustable trailer hitch assembly; 
         FIG. 9  is a partial cut-out cross-sectional view of the inventive adjustable trailer hitch assembly in a locked position preventing extension; 
         FIG. 10  is a partial cut-out cross-sectional view of the inventive adjustable trailer hitch assembly in an unlocked position permitting extension thereof; 
         FIG. 11  is a partial cut-out cross-sectional view of the inventive adjustable trailer hitch assembly in a locked position preventing pivoting; and 
         FIG. 12  is a partial cut-out cross-sectional view of the inventive adjustable trailer hitch assembly in an unlocked position permitting pivoting thereof. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in  FIGS. 1-4 , the adjustable trailer hitch assembly of the present invention, shown generally at  10 , includes a first weldment member  12  pivotally attached to a trailer  14 , and a second weldment member  16  moveably attached to the first member  12  via extension arms  18  and  20 . A lunette ring  22  connected to the second member  16 , the lunette ring  22  being attachable to a pintle hook included on a tow vehicle (not shown). A lunette ring is simply one of numerous vehicle connection elements that can be used with the present invention and is shown in the drawings for exemplary purposes only to facilitate an understanding of the invention. The present invention is not limited to the use of lunette rings. 
     The first member  12  includes a top plate  24 , a bottom plate  26 , and side plates  28  and  30  connecting the top  24  and bottom  26  plates (see also  FIG. 5 ). The plates are attached to one another using conventional welding techniques. Similarly, the second member  16  includes a top plate  32 , a bottom plate  34 , and side plates  36  and  38  connecting the top  30  and bottom  32  plates (see also  FIG. 6 ). The plates are attached to one another using conventional welding techniques. 
     The second member  16  includes a plurality of vertically spaced apertures  40  formed in the side plates  36 ,  38  thereof. The lunette ring  22  may be aligned at any vertical point along the length of the second member  16  by aligning apertures formed in the lunette ring  22  with desired apertures  40  formed in the second member  16  and inserting one or more locking pins  42  there through. 
     Extension of the second member  16  from the first member  12  is accomplished by the extension arms  18 ,  20  as follows. Extension arm  18  includes side plates  44 ,  46  connected at either end by pins  48  and  50  (see also  FIGS. 7   a - b ). Pin  48 , as well as side plates  44 ,  46 , includes an aperture  52  there though which is aligned with a corresponding aperture  54  formed in the side plates  36 ,  38  of the second member  16  and attached via a conventional locking pin  55  extending there through to provide a fixed pivoting connection point. Pin  50 , as well as side plates  44 ,  46 , includes an aperture  56  there through which is aligned with a channel  58  formed in the side plates  28 ,  30  of the first member  12  and attached via a convention locking pin  59  extending there through to provide a pivoting connection point moveable along the length of the channel  58 . 
     Extension arm  20  is a unitary member which is provided between the side plates  44  and  46  of extension arm  18 . Extension arms  18  and  20  are pivotally connected together, for example, at their midpoints by a pin  60  extending through apertures formed therein. One end of the extension arm  20  includes an aperture  62  there through which is aligned with a corresponding aperture  64  formed in the side plates  28 ,  30  of the first member  12  and attached via a conventional locking pin  65  extending there through to provide a fixed pivoting connection point. The other end of the extension arm  20  includes an aperture  66  there through which is aligned with a channel  68  formed in the side plates  36 ,  38  of the second member  16  and attached via a convention locking pin  69  extending there through to provide a pivoting connection point moveable along the length of the channel  68 . 
     With the first  12  and second  16  members in a first locked position, as shown in  FIG. 1 , the pins  59  and  69  will be located at the top portions of the channels  58  and  68 , respectively. When the second member  16  is moved to an extended second position, as shown in  FIG. 2 , the pins  59  and  69  will move along the respective channels  58  and  68  to allow for such extension. The bottoms of the channels  58  and  68  will stop movement of the pins  59  and  69 , respectively, and provide for a maximum extension point. In this manner, the trailer hitch assembly  10  of the present invention may be extended to various lateral extended positions to accommodate the pintle hook (or other connection element) on the tow vehicle. This is particularly desirable in rough terrains where the tow vehicle cannot be moved to a position directly adjacent the trailer. By adjusting the vertical position of the lunette ring  22  along the length of the second member  16 , deviations in the height of the terrain may also be accommodated. Thus, the inventive trailer hitch assembly  10  provides for a wide adjustment range for attaching the trailer to the tow vehicle. It should be noted that while the channels  58  and  68  are illustrating in the drawings as adjacent the tops plates  24  and  32  of the first  12  and second  16  members, respectively, one skilled in the art will appreciate that the channels  58  and  68  could also be provided adjacent the bottom plates  26  and  34  of the first  12  and second  16  members, respectively, without departing from the spirit and scope of the present invention. 
     The trailer hitch assembly  10  of the present invention is maintained in a first locked position by spring loaded locking pins  70  extending through apertures formed in the top  24  and bottom  26  plates of the first member  12 . The locking pins  70  are attached to the top  24  and bottom  26  plates of the first member  12  and are biased in a locked position as shown, for example, in  FIG. 9 . The top  32  and bottom  34  plates of the second member  16  include ramped surfaces  72  provided adjacent locking apertures  74 . As the second member  16  is moved from an extended position to a locked position, the ramped surfaces  72  will engage the ends of the locking pins  70 , pushing against the force of the spring and moving the pins  70  against their biased position as they move up the length of the ramped surfaces  72 . Once the second member  16  is in a locked position, as shown in  FIG. 9 , the locking pins  70  will align with the locking apertures  74  and automatically extend there though via the force of the associated springs, thus locking the trailer hitch assembly  10  in the locked position. 
     Extension of the second member  16  is accomplished by a user grasping rings  76  extending through the locking pins  70 . The rings  76  may be made of wire, rope, or other suitable material, and are provided for ease of use since both the top and bottom locking pins  70  must be disengaged before extension of the second member  16  can occur. In use, a user may place his/her foot in the bottom ring  76  and grasp the top ring  76  with his/her hand. Pulling the locking pins  70  against the force of the springs will disengage them from the locking aperture  74 , as shown in  FIG. 10 , and allow the second member  16  to be extended from the first member  12 , as shown in  FIGS. 2 and 4 . 
     Pivotal attachment and movement of the trailer hitch assembly  10  is accomplished as follows. Typically, before assembly, a plate  78  will be welded to the top and bottom of the trailer  14 . Swivel pins  80  are attached to, and extend through, the top  22  and bottom  24  plates of the first member  12 , and also extend through the plates  78  to pivotally connect the trailer hitch assembly  10  to the trailer  14 . Pivot locking pins  82  are provided in the top  24  and bottom  26  plates of the first member  12 . The pins  82  extend through the top  24  and bottom  26  plates and also through corresponding apertures  84  formed in the welded plates  78 . The pins  82  are biased to a locked position, as shown in  FIG. 11 , to prohibit pivoting of the trailer hitch assembly  10 . Typically, the apertures  84  will be formed in the plates  78  at a location to lock the trailer hitch assembly  10  at a center position, as shown by dotted line  86  in  FIGS. 3 and 4 . 
     Pivoting of the trailer hitch assembly  10  is accomplished by a user grasping the rings  76  that also extend through the locking pins  82 . In use, a user may place his/her foot in the bottom ring  76  and grasp the top ring  76  with his/her hand. Pulling the locking pins  82  against the force of the springs will disengage them from the apertures  84 , as shown in  FIG. 12 , and allow pivoting movement of the trailer hitch assembly  10  in either lateral direction, as shown in  FIGS. 3 and 4 . Pivoting of the trailer hitch assembly  10  can occur either when the second member  16  is in a locked position (see  FIG. 3 ) or when the second member  16  is in an extended position (see FIG.  4 ). Pivoting movement in each lateral direction is limited by the associated side plate  28  or  30  of the first member  12  coming into contact with either the trailer  14  or the welded plate  78 . Upon rotation back to the center position (see dotted line  86  in  FIGS. 3-4 ), the pivot locking pin  82  will automatically be biased through the aperture  84  and lock the trailer hitch assembly  10  into its center-aligned position. 
     The adjustable trailer hitch assembly  10  of the present invention allows rapid hook-up of the trailer  14  to various vehicles in various types of terrain because the driver can be less precise in positioning the tow vehicle relative to the trailer  14 . Additionally, only one individual, typically the driver, is required to attach the trailer  14  to the tow vehicle, which minimizes the need for an additional individual to direct the driver from the outside and keeps other individuals out of harm&#39;s way. The tow vehicle can be positioned at a point near the trailer  14 , and the adjustable trailer hitch assembly  10  of the present invention can be adjusted in the vertical, lateral and fore/aft directions to connect the trailer  14  to the tow vehicle. In one embodiment, the tow vehicle connection element may be offset laterally up to 8.5-inches from the center line of the trailer  14 , and up to 7-inches forward of the normal towing position. Additionally, 14-inches of vertical adjustment is typically provided to connect tow vehicles to with varying connection element heights. However, one skilled in the art will realize that these ranges of adjustability are exemplary only and various other ranges of adjustability may be implemented depending on the scalability of the assembly and the intended field of use and trailer capacity without departing from the spirit and scope of the present invention. 
     In operation, an operator would back the tow vehicle up to the trailer  14 . The locking pins  42  on the lunette ring  22  would be removed to adjust the lunette ring  22  to the proper height to meet the height of the tow vehicle pintle hook. The extension  70  and pivoting  82  locking pins would then be released to allow the trailer hitch assembly  10  to swing (pivot) and extend. The lunette ring  22  is then positioned into the pintle hook of the tow vehicle. After connection of typical safety chains and electrical/air connections, the driver would then pull forward causing the trailer tongue to align and the pivot locking pin  82  to automatically lock in place. The tow vehicle could then be put in a reverse position and backed up for the extension arms  18  and  20  to collapse cause the extension pin  70  to automatically lock in place and secure the second member  16  to the locked position. The operator then could secure the safety latch with a padlock or linchpin to ensure that the main latch pins are secure. The trailer  14  is then ready for towing. 
     In an additional mode of operation, the operator would back the tow vehicle up to the trailer  14 . The locking pins  42  on the lunette ring  22  would be removed to adjust the lunette ring  22  to the proper height to meet the height of the tow vehicle pintle hook. The extension  70  and pivoting  82  locking pins would then be released to allow the trailer hitch assembly  10  to swing (pivot) and extend. The lunette ring  22  is then positioned into the pintle hook of the tow vehicle. After connection of typical safety chains and electrical/air connections, the driver could then simply pull away without having to back the vehicle up to lock the trailer hitch assembly  10  to a locked position. As the driver moves away, pivoting of the trailer hitch assembly  10  to a center position would automatically cause the pivot locking pins  82  to engage the apertures  84  and lock the trailer hitch assembly  10  to its center-aligned position. As the vehicle moves forward and slows, the momentum of the trailer  14  would push it forward causing the extension arms  18  and  20  to collapse and the first  12  and second  16  members to be pushed together, so that the extension locking pins  70  would automatically engage the apertures  74  after riding up the ramped surfaces  72  and secure the second member  16  to its locked position. It is contemplated that all of the elements of the trailer hitch assembly  10  be made of a high strength steel so that the assembly  10  may be operational for towing in either locked or extended positions. 
     As one skilled in the art will appreciate, the inventive trailer hitch assembly  10  allows ease of operation to connect a trailer  14  to a tow vehicle. While the invention has been described herein as using a lunette ring  22  to connect the trailer  14  to the tow vehicle, this is for exemplary purposes only and is in no way meant to limit the scope of the present invention. Other types of vehicle connection elements including ball hitches, etc. may be implemented with the inventive assembly  10  depending upon the attachment mechanism used by the tow vehicle without departing from the spirit and scope of the present invention. 
     The inventive design offers a solution that is inherently not susceptible to operational failure due to sand and dirt infiltration. But utilizing rotating pins and keeping sliding surfaces to a minimum and vertically oriented, dirt entrapment points are reduced. The scissor design of the extension arms  18  and  20  allows a robust structure with a large vertical adjustment capability and rigidity when in the extended position, in addition to being stiff when in a jack-knifed position. The inventive design is scalable to meet the needs of various applications and can provided operational reliability, life expectancy and range of motion that meets or exceeds typical requirements. 
     While the present invention has been described with the particular reference to the drawings, it should be understood that various modifications could be made without departing from the spirit and scope of the present invention. For example, while a scissor design of the extension arms is described for extension of the assembly, one skilled in the art will understand that other types of apparatus may be implemented for such extension without departing from the spirit and scope of the present invention. Those skilled in the art will appreciate the various other modifications and alterations could be developed in light of the overall teachings of the disclosure. The presently preferred embodiments described herein are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof.

Technology Category: b