Abstract:
A hitch pin assembly for securing a shank member to a hitch receiver tube to minimize relative motion between the shank member and receiver tube, comprising an elongated pin having a threaded portion, a threaded nut, an elastomer piece, and a shank member which are mated for tightened engagement compressing the elastomer piece so as to firmly engage the receiver tube. The shank member may include a slot for a corresponding threaded nut and elastomer piece so when the pin is tightened, the nut compresses the elastomer against the interior wall of the shank surface and upwardly, thereby restraining movement of the threaded nut and dampening movement of the shank inside the hitch receiver tube.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of provisional U.S. patent application Ser. No. 61/723,221, filed on Nov. 6, 2012, and provisional U.S. patent application Ser. No. 61/723,252, filed on Nov. 6, 2012, which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to the field of securing devices for receiver hitch assemblies and particularly to the field of securing devices that minimize the relative movement between the receiver and shanks of such assemblies and securing, locking and preventing loosening of threaded connections. 
       BACKGROUND OF THE INVENTION 
       [0003]    Many vehicles today are equipped with receiver-type trailer hitches. These types of trailer hitches typically are a square tube, normally 1¼″ or 2″ internal height and width, attached to the undercarriage of the vehicle. A second tube acts as a shank and includes outer dimensions slightly smaller than the internal dimensions of the receiver tube and is slidable within the receiver tube. The shank member is connected to the receiver tube by a pin inserted through the two tubes and locked or clipped to prevent relative movement between the two tubes. 
         [0004]    Moreover, conventional techniques for locking threaded connections involve either mechanical metal split rings, external/internal tooth or Schnoor type metal spring metal-to-metal designs that gouge into the substrate causing surface deformities that can lead to accelerated rusting due to the penetration of the protective coating media by the locking device. 
         [0005]    In highly corrosive environments like a receiver style hitch that encounters a variety of caustic substances, keeping the powder coating or paint on the hitch unmarred is critical when attaching, securing and removing towing products and accessories using methods that eliminate or remove dangerous and unwanted movement and noise in the hitch connection. 
         [0006]    In another embodiment of the receiver-type trailer hitches, the shank is a solid, substantially square bar. Usually a 1¼″ or 2″ square with rounded corners. The solid shank is used more often with 1 or 1¼″ type hitch mounts. 
         [0007]    The shank member may include a standard ball-mount for engaging with the hitch of a trailer or other wheeled vehicle. Another popular use for receiver hitches is the use as a coupling device for installing equipment racks, ski carriers, storage boxes and other types of carriers have been designed to use the above-described second tube to engage within a receiver hitch tube. This provides a universal system that allows a vehicle user to be able to use various trailer and carriers with a single coupling system. 
         [0008]    A particular problem with the use of these receiver coupling systems is the clearance between the internal dimensions of the receiver tube and the external dimensions of the shank member. These tubes by necessity must have sufficient clearance to be able to be easily telescoped together. However, this clearance between the two tubes causes relative movement between the two tubes. The shank member tends to rattle or chatter within the receiver tube. This rattle or chatter is at best an annoyance and at worst can distract the driver or cause damage to the trailer or the carrier. 
         [0009]    There have been a number of attempts to solve this problem in the past. These attempts all required the use of specially designed receivers, shanks, or accessories in order to reduce the rattle between the receiver and shank. Examples of these prior attempts are disclosed in U.S. Pat. No. 5,423,566; U.S. Pat. No. 5, 593,172; U.S. Pat. No. 5, 735,539; U.S. Pat. No. 5,879,102; U.S. Pat. No. 5,988,667; U.S. Pat. No. 6,010,049; U.S. Pat. No. 6,010,143; U.S. Pat. No. 6,010,144; and U.S. Pat. No. 6,105,989. These prior art devices either require specially designed receivers and shanks or use extraneous mounting devices to minimize the rattle between the receiver and the shank. 
         [0010]    At present, there are a number of motion reducing designs for receiver style hitches useful for both hollow shanks and solid shanks. However, there persists a need for a device that will minimize the rattle between the receiver tube and the shank member. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention addresses a new assembly and method of restraining motion in receiver style hitch connections, and includes without limitation securing, locking and preventing loosening of threaded connections. The present invention utilizes an elastomeric material in a piece which can take the form of a deformable washer or an elastomer block with a threaded compressible connection to effect a locked bolt and nut connection. 
         [0012]    At present there are a number of motion reducing designs for receiver style hitches useful for both hollow shanks and solid shanks. The present invention utilizes a shank ball mount with a slot created on one side of the shank. Into this slot is placed a threaded nut and elastomer piece. This assembly is slid into the hitch with the hitch wall holding the nut and elastomer in the slot. A threaded pin is then inserted from the opposite side to engage the threaded nut and pull the shank to the threaded pin head side of the hitch receiver wall. When the pin is tightened the nut squeezes the elastomer causing the material to flow upward and downward into the small cavity between the shank surface and the inside of hitch tubing surface. The elastomer displaces the open space to dampen movement of the shank inside the hitch receiver tube. 
         [0013]    The surface area, i.e., diameter and thickness, and durability of the elastomer material specification relate to the foot pounds of force required to affect the locking, dampening and noise controlling technique. 
         [0014]    The locking technique and assembly of the present invention is induced by the threaded tightening of the connection causing the elastomer to flow outward past the shank diameter whereby the elastomer impacts the receiver tubing and fills the unsupported portion of the cavity which effectively locks the connection with the energy stored in the incompressible elastomer. This securing device minimizes the rattling and relative movement of the shank member and the receiver tube due to the clearance between the shank member and the receiver tube. A preferred embodiment of the present invention solves these problems by providing the securing device for use in most receiver assemblies. The present invention allows users to install the securing device of the preferred embodiments without the need for special tools or modification of the receiver assemblies. The securing device also includes a hitch pin assembly. The hitch pin includes a threaded portion that engages the nut assembly. The shank member is inserted into the receiver tube until the opposing side holes of the shank member are aligned with opposing side holes in the receiver tube. The hitch pin is then inserted through the side holes of the receiver tube and the shank member until the threaded portion of the hitch pin engages the nut mounted within the shank member. The hitch pin is then rotated relative to the nut to clamp the shank member against the receiver tube and expand the elastomer against the top and bottom internal surface of the receiver tube. A lock or clip can be attached to the end of the hitch pin to prevent accidental or unauthorized removal of the hitch pin from the receiver assembly. A bushing can also be used over the reduced diameter portion of the hitch pin after it engages the nut. 
         [0015]    The present invention further comprises an assembly for locking a threaded connection, which includes an elongated pin having a threaded portion, a nut having a threaded hole for engagement with the threaded portion of the elongated pin, an elastomer washer having a hole for receiving the elongated pin; and a first component having a hole for receiving the elongated pin such that mated coupling of the elongated pin with the hole of the elastomer washer and a component having a hole for receiving the elongated pin such that mated coupling of the elongated pin with the hole of the elastomer piece and the component are secured when the elongated pin is tightened in threaded engagement with the threaded hole of the nut such that the elastomer washer is compressed between the nut and the component. The connection tension of the assembly of the present invention corresponds to the elastomer surface area, thickness and density. As used herein, an elastomer piece is a conformable material configured in any size and shape, including, without limitation a washer or block, which is adaptable for use to lock, restrain, or dampen a joint connection. 
         [0016]    These and other features will be evident from the ensuring detailed descriptions of preferred embodiment and from the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1A  is a side perspective view of a prior art hitch ball assembly. 
           [0018]      FIG. 1B  is an exploded perspective view of a hitch ball assembly utilizing securing device for receiver hitches according to the present invention. 
           [0019]      FIG. 2  is a side perspective view of the thread locking assembly of the present invention in use. 
           [0020]      FIG. 3  is a perspective view of the present invention in use. 
           [0021]      FIG. 4A  is a side perspective view of the present invention in unengaged position. 
           [0022]      FIG. 4B  is another side perspective view of the present invention in unengaged position. 
           [0023]      FIG. 5A  is an exploded view of the hitch receiver of the present invention including the thread locking and motion dampening elastomer components in unassembled position. 
           [0024]      FIG. 5B  is another exploded view of the present invention shown with an end perspective of a receiving shank in unassembled position. 
           [0025]      FIG. 6  is a side perspective view of the present invention in assembled position. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0026]    Now referring to the drawings,  FIG. 1A  shows a prior art hitch assembly  40 P and hitch receiver  30 P. A preferred embodiment of the present invention is illustrated in  FIGS. 1B-6 . It is to be expressly understood that the descriptive embodiment is provided herein for explanatory purposes only and is not meant to unduly limit the claimed inventions. The preferred embodiment of the present invention is intended for use with receiver hitch systems including trailer mounts as well as carriers. The preferred embodiment may be used for original equipment installations and as an after market item. 
         [0027]    In the preferred embodiment, as shown in  FIG. 1B , receiver hitch assembly  40  includes receiver tube  30  mounted beneath a bumper of a vehicle. Receiver tube  30  is mounted to the vehicle by well known mounting techniques, such as by bolting or welding. In this preferred embodiment receiver tube  30  includes either 1½ inch square tubing or 2 inch square tubing (internal dimensions). It is to be expressly understood that other sizes of shapes of tubing can be used as well. 
         [0028]    Shank member  4 , as shown in  FIGS. 1B-6  includes a portion having a shape similar to the shape of the internal portion of receiver tube  30 A and an external diameter slightly less than the internal diameter of the receiver tube  30 . This enables the shank member  4  to be inserted within the receiver tube  30  in a telescoping manner. In most typical receiver hitch assemblies, the difference in the dimensions of the internal portion of the receiver tube  30  and the external portion of the shank member  304  is about 1/16 inch (one-sixteenth inch) to allow the shank member  4  to be easily inserted within the receiver tube  20 . In the exemplary embodiment described herein, shank member  4  is illustrated a having a trailer hitch ball mounted thereon. It is to be expressly understood that the claimed inventions also includes shank members having carriers mounted thereon, such as bicycle carriers, ski carriers, cargo compartments, platforms and other types of receiver mounted devices. 
         [0029]    As shown in  FIGS. 1B  ,  2 A,  2 B,  3 A and  3 B, receiver tube  2030  includes opposing side holes  32 - 34 . The shank member  4  also includes a through hole  42  that aligns with the opposing side holes  32 - 34  of the receiver tube  30 A as the shank member  4  is inserted into the receiver tube  30 . Hitch pin assembly  20  is inserted through side holes  32 - 35  of the receiver tube  30  and the side hole  42  of the shank member  304  to the receiver tube  30 . 
         [0030]    Now referring to  FIGS. 4A-4B  in conjunction with the latter illustrations of the in a preferred embodiment of the present invention, hitch pin assembly  20  includes a head portion  14 , an elongated portion  18 , a locking groove  26  and a tapered end  44 . Elongated portion  18  includes a threaded section  6  and a reduced diameter portion  22 . The threaded section  6  of elongated portion  18  is spaced a distance “d” from head portion  14 . This distance “d” is preferably equal to or less than the combined thicknesses of the side walls of the receiver tube  30  and the shank member  4 . In the preferred embodiment, head portion  14  includes a hex shaped detail, but could also be a wing or handle shape, square or alien head or any other shape or configuration. 
         [0031]    Hitch pin assembly  10  also includes a nut assembly  20 . Nut assembly  20  includes a nut  22  having an internal threaded portion  6  for mating engagement with threaded section  6  of pin  14 . The outer dimension of the nut  22  is selected to prevent the nut from rotating with the internal portion of the shank member  4  as discussed below. Elastomer washer  24  is positioned to the inside of nut  22 . The elastomer washer  24  is sized so that it is in a state of compression when the nut  8  and elastomer block  2  are inserted within the shank member  4 , as discussed below. Another component of hitch pin assembly  10  is a lock engageable over the tapered end  44  of pin  14  and locks onto locking groove  26 . 
         [0032]    Now referring to  FIGS. 5A-5B  illustrating the preferred embodiment in use, nut  8  and elastomer block  2  are inserted within the matching cavity  36  on the side of shank member  4 . Elastomer block  2  is positioned between the inner side wall of the shank member  4 , slot  36  and the nut  2  to maintain the alignment between the threaded portion  6 , shank member  4 , hole  42  and the receiver tube  30  side holes  32 ,  34 . 
         [0033]    Shank member  4  is then ready for insertion into the receiver tube  30  once the nut  8  and elastomer block  2  have been installed within the shank member  4 . Shank member  4  is “telescoped” within receiver tube  30  until the side hole  42  is aligned with the side holes  32 ,  34  of the receiver tube. Pin assembly  20  is then inserted into the side holes  32 ,  34  until the threaded portion  6  of the pin assembly  20  engages the threaded portion  6  of pin assembly  20 . Pin  14  is then rotated relative to the nut  16  to tighten the nut  16  against the elastomer block  2  which in turn is tightened against the inside wall of pocket slot  36  of the shank member  4 . The size of the nut  8  is selected to ensure that the nut cannot rotate within the shank member  4 . As the pin  14  continues to be rotated relative to nut  16 , nut  16  exerts pressure against elastomer block and inner side wall of the shank member  4  which in turn clamps against the inner side wall of the receiver tube  30 . The hex head of pin  14  in combination with the use of a wrench allows the nut  16  to be sufficiently tightened against the side of the elastomer block  2  and wall of the shank member  4  so that the top and bottom of the elastomer block  2  flows out of the top and bottom of the shank as shown in  FIG. 6  and restrains the relative movement between the shank member  4  and the receiver tube  30 , while the shank is simultaneously compressed against the inside surface of the receiver tube  30  and with any resultant movement being minimized or even eliminated. Thus the rattling of the shank member and associated trailer or carrier mounts is minimized. Wear between the shank member and receiver tube and the distracting aspect of noise is minimized as well. 
         [0034]    A lock can then be secured and locked onto the end  44  of the pin assembly  20  to prevent unauthorized removal of the pin assembly  20  and the shank member  34 . In another preferred embodiment, pin  14  includes a groove  26  to engage a clip pin to prevent the pin from loosening or being removed. Other types of securing mechanisms can be used as well to prevent the removal of pin  14  from the shank member  4  and receiver tube  30 . 
         [0035]    In another alternative embodiment, bushing  42  can be provided to go over the elongated portion  18  of pin  14 . Bushing  42  butts up against the shoulder  44  such that recessed portion  46  seats into locking groove  26  of the pin to ensure that the pin  14  fits tightly within the side holes  32 ,  34  and of the receiver tube  30  of the shank member  4 . As previously described, an alternative lock to ensure a tight fit between the components can be utilized. 
         [0036]    It is to be expressly understood that these exemplary embodiments are provided for descriptive purposes only and not meant to unduly limit the scope of the claimed inventions. Other embodiments are also considered to be within the scope of the present inventions.