Abstract:
A new and simple hitch assembly comprising a vertically adjustable bar (vertical bar) secured within a mounting sleeve which in turn is securely attached to a hitch bar. A vertical securing pin releasably engages the vertical bar and is maintained in place by a spring, the pin and spring comprising the vertical securing mechanism. The hitch assembly mates with standard hitch receivers such that the relative height of a hitch ball may be varied. The hitch assembly is easy to manufacture and is durable, strong, and stable during towing. Such a hitch assembly is of simple design and has few movable parts. Such a hitch assembly is also compact and has a large range of height adjustment as it is mountable in alternative vertical orientations. The vertical bar has a series of holes in which the vertical securing pin is engaged.

Description:
BACKGROUND 
   1. Technical Field 
   The present invention generally relates to trailer hitches for connecting a trailing vehicle to a towing car, truck, or other vehicle. The disclosed hitch assembly provides a means for easily adjusting the vertical position of an attached ball hitch with respect to the hitch receiver so as to accommodate a maximum variety of vehicles having a hitch assembly. 
   2. Description of Related Art 
   Many people have a need to haul something behind their car or truck. Typically, a trailer or trailing vehicle is coupled to its frame and the towing vehicle with a hitch assembly. The hitch assembly includes a ball hitch that couples to a ball socket on the front of the trailer. A problem occurs when the ball hitch is higher or lower than the ball socket. For instance, a small trailer might sit low to the ground. When towed behind a taller vehicle, the trailer will ride at an angle because the ball socket will have to be tipped upwards to reach the higher ball hitch. 
   Therefore, a need exists for a hitch assembly that allows the ball hitch to be lowered or raised to roughly match the height for the ball socket. The present invention fills these and other needs as detailed more fully below. 
   SUMMARY OF THE INVENTION 
   The object of the present invention is to provide for a new and useful hitch assembly wherein the vertical height of a draw bar with relative to a hitch bar is easily adjustable. A new adjustable hitch assembly mates with standard hitch receivers of vehicles such that the height of a hitch ball relative to a trailor vehicle may be varied. The hitch assembly interoperates with many makes and models of trucks and automobiles. The disclosed hitch assembly is easy to manufacture and is durable, strong, and stable during towing. Such a hitch assembly is of simple design with few movable parts. Such a hitch assembly is also compact and has a large range of height adjustment as it is mountable in alternative vertical orientations. 
   The adjustable hitch assembly comprises a draw bar mounted to a vertical bar, the vertical bar being slidably mounted inside a mounting sleeve, which sleeve is, in turn, mounted to a hitch bar. The draw bar, vertical bar, mounting sleeve and hitch bar form a simple interlocked device. The hitch bar is secured to a hitch receiving mount by a hitch pin or other connecting mechanism. The vertical bar includes a series of holes through which the vertical position of the vertical bar is secured. A single pin is inserted into one or more of these holes. Such pin is securely maintained in position by a spring or other tension or compression mechanism. 
   The invention may comprise other structures in combination with the elements of a hitch receiver. A hitch ball may also be provided with the hitch ball being releasably securable to a draw bar. 
   The invention accordingly comprises the features described more fully below, and the scope of the invention will be indicated in the claims. Further objects of the present invention will become apparent in the following detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein: 
       FIG. 1  is a perspective view of one embodiment of a hitch assembly according to the present invention; 
       FIG. 2  is a side view of the embodiment of the hitch assembly shown in  FIG. 1 ; 
       FIG. 3  is a perspective view of the embodiment of the hitch assembly shown in  FIG. 1  showing vertical securing holes in the vertical bar; and, 
       FIG. 4  is an overhead perspective view of an alternative embodiment of the hitch assembly according to the present invention. 
   

   REFERENCE NUMERALS 
   
       
         102  Hitch Bar 
         104  Vertical Bar 
         106  Mounting Sleeve 
         108  Draw Bar 
         110  Hitch Ball Hole 
         112  Vertical Securing Mechanism 
         114  Spring Bar 
         116  Spring 
         118  Hitch Pin 
         120  Safety Catch 
         122  Vertical Securing Hole 
         124  Hitch Bar Hole 
         128  Vertical Securing Pin 
     
  
   DETAILED DESCRIPTION 
   While the invention is described below with respect to embodiments, and even a preferred embodiment, other embodiments are possible. The concepts disclosed herein apply equally to other devices for providing a vertically adjustable towing hitch. 
   The present invention is directed to a vertically adjustable hitch assembly that allows for ready manual adjustment of the relative height difference between a hitch receiver and the tongue of a trailing vehicle so that a tractor vehicle and trailing vehicle can be easily and properly coupled. Such a vertically adjustable hitch assembly provides the proper height and connecting orientation for safe towing. 
     FIG. 1  shows a perspective view of one embodiment of the present invention. With reference to  FIG. 1 , the adjustable hitch assembly comprises a draw bar  108  mounted to a vertical bar  104 , the vertical bar  104  being slidably mounted inside a mounting sleeve  106 . The mounting sleeve  106  is mounted to a hitch bar  102  which removably fits into a hitch receiving assembly or mount of a tractor vehicle (not shown). The draw bar  108 , vertical bar  104 , mounting sleeve  106 , and hitch bar  102  form a simple interlocked device. Simplicity is advantageous in towing, and especially in the towing rental business. 
   In one embodiment, the hitch bar  102  is secured to a hitch receiving mount (not shown) by one or more hitch pins  118  or other connecting mechanism. Each hitch pin  118  passes through a hitch bar hole  124  in each side of the hitch bar  102  and corresponding holes in a hitch receiving mount (not shown). In a preferred embodiment, a single hitch pin  118  passes through both sides of the hitch bar  102  so as to provide a simple mechanism to attach the hitch assembly to a hitch receiving mount. In one embodiment, there are multiple sets of hitch bar holes  124  so as to accommodate a variety of desired distances between a hitch mount (not shown) and the tongue of a trailing vehicle (not shown). Such a simple mechanism accommodates a wide variety of vehicles and is simple to operate. Such simplicity provides increased safety and reliability for those renting a hitch assembly, especially to those who may be unfamiliar with towing and towing equipment. 
   In one embodiment, and with reference to  FIG. 1 , a vertical bar  104 , having a hollow, square cross-section, is slidably coupled to a mounting sleeve  106 . The mounting sleeve  106  is permanently attached to the hitch bar  102 . The vertical bar  104  may be positioned at various intervals along its length bound only by a draw bar  108  on one end, and an optional safety catch  120  on the other end. In one embodiment, a safety catch  120  is a piece of metal welded to and protruding from the edge of the vertical bar  104  which prevents the vertical bar  104  from exiting the mounting sleeve  106  even when the vertical securing pin  128  is disengaged. Other embodiments of a safety catch  120  are possible including a removable or adjustable element. Such arrangement of the vertical bar  104  provides increased safety to a user during installation and adjustment. 
     FIG. 3  shows an alternative perspective view of the universal adjustable lift/drop hitch shown in  FIG. 1 . With reference to  FIG. 3 , the position of the vertical bar  104  is maintained by engaging a vertical securing pin  128  in one of the vertical securing holes  122  in the vertical bar  104 . The vertical securing pin  128  is held in place by a vertical securing mechanism  112  comprising a spring  116  and a spring bar  114  located within the vertical securing mechanism housing  117 . Once the vertical securing pin  128  is engaged in a hole  122 , the spring  116  maintains a force against the vertical securing pin  128  and prevents it from disengaging. The compression of the spring  116  and the position of the vertical securing pin  128  are bound by a spring bar  114  abutting the housing of the vertical securing mechanism  112 . The spring bar  114  provides a gripping surface by which the spring  116  may be manually compressed there by releasing the vertical securing pin  128  from a securing hole  122 .  112 . The spring bar  114  provides a gripping surface by which the spring  116  may be manually compressed there by releasing the vertical securing pin  128  from a securing hole  122 . 
   The position of the vertical bar  104  may be changed by first compressing the spring  116  thereby allowing the vertical securing pin  128  to slide free from the corresponding vertical securing hole  122 . At this point, the vertical bar  104  is free to move along the path defined by the mounting sleeve  106 . Once a new vertical position is selected, the vertical securing pin  128  may be re-engaged in a vertical securing hole  122  by releasing the compression on the spring  116 . 
   Other cross-sections for the various hitch assembly members are possible. A square cross-section provides flat surfaces for easy welding or other connecting and assembly means. A square cross-section also provides an advantageous and strong geometry to resist torque forces generated during towing. 
     FIG. 2  shows a side view of one embodiment of the hitch assembly according to the present invention. With reference to  FIG. 2 , the vertical bar  104  and mounting sleeve  106  are mounted in a non-perpendicular arrangement relative to each other. In this arrangement, the vertical bar may not be exactly perpendicular to the horizontal or to the ground. Such arrangement provides an ergonomic benefit in adjusting the vertical position of the vertical bar  104 . In this arrangement, the vertical securing mechanism  112  and vertical bar  104  are mounted perpendicularly to each other which allows the vertical securing pin  128  to align properly with vertical securing holes  122  and provides an improved angle relative to the horizontal at which to compress the spring  116 . The vertical securing mechanism  112  is not parallel to the horizontal which allows water and other potentially corrosive agents to drain and fall free from it during the securing mechanism housing  117  during towing. To state differently, the housing  117  has a slight negative angle (less than 90 degrees) relative to the hitch bar  102  as shown in this figure. In this embodiment, the draw bar  108  and hitch bar  102  are still maintained in a generally horizontal and parallel orientation for establishing and maintaining proper connection between a trailing vehicle and a tractor vehicle. However, other geometries of these components are possible. 
     FIG. 2  also illustrates that the entire hitch assembly may be rotated 180 degrees about the hitch bar  102  axis to increase the range of vertical position of the draw bar  108 . This is accomplished by removing the hitch pin  118  from the hitch bar hole  124 , removing the hitch bar  102  and the entire hitch assembly from the hitch receiving assembly of a tractor vehicle, rotating the entire hitch assembly, and finally repositioning it in the hitch receiving assembly. It would then be necessary to re-insert the hitch pin  118  to secure the hitch assembly to the tractor vehicle. When the draw bar  108  is mounted in the hitch receiving assembly below the hitch bar  102 , this position is considered a first position. Similarly, when the draw bar  108  is mounted in the hitch receiving assembly above the hitch bar  102 , this position is considered a second position. In the second position, a hitch ball (not shown) would be mounted on the opposite side of the draw bar  108  for coupling of the trailing vehicle to the hitch assembly. Such versatile hitch assembly simultaneously provides a simple apparatus and a relatively large range of vertical adjustment. Such a hitch assembly is released, rotated, and re-attached to a tractor vehicle without the use of tools. 
   The present invention allows for a quick and easy method to install a hitch assembly to a tractor vehicle, and to change the vertical position of the draw bar  108  of the hitch assembly prior to attaching a trailing vehicle to the tractor vehicle. The method is comprised of the following steps: (1) inserting the hitch assembly into the hitch receiving assembly; (2) inserting the hitch pin  118  through the hitch bar  102  and hitch receiving assembly; (3) compressing the spring  116  of the vertical securing mechanism  112  thereby releasing the vertical securing pin  128  from the vertical bar  104 ; (4) selecting a desired draw bar  108  height; and (5) re-engaging the vertical securing pin  128  into one of the vertical securing holes in the vertical bar  104 . The hitch assembly of the present invention is then ready to receive a trailor vehicle. 
   The foregoing discussion of the invention has been presented for purposes of illustration and description. Further, the description is not intended to limit the invention to the form disclosed herein. Consequently, variation and modification commensurate with the above teachings, within the skill and knowledge of the relevant art, are within the scope of the present invention. The embodiment described herein and above is further intended to explain the best mode presently known of practicing the invention and to enable others skilled in the art to utilize the invention as such, or in other embodiments, and with the various modifications required by their particular application or uses of the invention. It is intended that the appended claims be construed to include alternate embodiments to the extent permitted.