Abstract:
A hitch pin securing system for receiver mounted accessories. The present invention provides a device for securely clamping a shank tube to a receiver tube. This securing device minimizes the rattling and relative movement of the shank tube and the receiver tube due to the clearance between the shank tube and the receiver tube. The securing device includes a threaded nut or bushing mounted within the shank tube. A hitch pin is inserted through the receiver tube and shank tube and engages the shank tube nut. A locking handle is used to tighten the hitch pin relative to the shank tube nut. Once the hitch pin is tight, the handle is pivoted relative to the hitch pin to cause a cam surface to tighten the shank tube nut against the shank tube which forces the shank tube in tight engagement against the receiver tube.

Description:
FIELD OF THE INVENTION  
       [0001]     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.  
       BACKGROUND OF THE INVENTION  
       [0002]     Many vehicles today are equipped with receiver-type trailer hitches. These types of trailer hitches typically are a square tube, normally 11/4 or 2 inches 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 is slidable within the receiver tube. The shank tube 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.  
         [0003]     The shank tube 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 onto the vehicle. Bicycle carrier 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 trailers and carriers with a single coupling system.  
         [0004]     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 tube. 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 tube 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.  
         [0005]     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 devices either require specially designed receivers and shanks or use extraneous mounting devices to minimize the rattle between the receiver and the shank.  
         [0006]     Another existing system for minimizing the movement and rattle between a receiver tube and shank tube is the Silent Hitch Pin by Let&#39;s Go Aero, Inc. as described in U.S. Pat. Nos. 6,409,203; 6,609,725; and 6,945,550 and in U.S. Published Application 20050236811. This system uses a resilient nut mounted within the receiver tube. The hitch pin includes a threaded portion which engages the resilient nut to secure the shank tube against the receiver tube to minimize the relative movement and rattle between the receiver tube and shank tube. These systems work well but often require tools to tighten the hitch pin with the resilient nut.  
         [0007]     There presently is a need for a device that will minimize the rattle between the receiver tube and the shank tube. There is a further need for a device that can be used with most of the existing receiver systems presently in use. There is also a need for a device that can be securely tightened without the need of tools.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention solves these and other problems by providing a device for securely clamping a shank tube to a receiver tube. This securing device minimizes the rattling and relative movement of the shank tube and the receiver tube due to the clearance between the shank tube and the receiver tube.  
         [0009]     The present invention, in a preferred embodiment, solves these problems by providing the securing device for use not only in original equipment installations but also for use as an “after market” device that can be installed by a user in most receiver assemblies.  
         [0010]     In a preferred embodiment of the present invention, the securing device includes a spring nut assembly. The spring nut assembly is inserted within the internal cavity of the shank tube until the nut is aligned with opposing side holes in the side walls of the shank tube. The spring maintains the nut in alignment with the opposing side walls.  
         [0011]     The securing device also includes a hitch pin assembly as well. The hitch pin includes a threaded portion that engages the spring nut assembly. The shank tube is inserted into the receiver tube until the opposing side holes of the shank tube 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 tube until the threaded portion of the hitch pin engages the nut mounted within the shank tube. The hitch pin is then rotated relative to the nut to clamp the shank tube against the receiver tube.  
         [0012]     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.  
         [0013]     Other embodiments of the present invention include using an elastomer in place of the spring on the spring nut assembly. Also, the nut may be held in alignment with the opposing side holes by adhesives, welding or other fastening techniques. One of the side holes may also be threaded instead of using a nut.  
         [0014]     The present invention provides a mechanism for ensuring the hitch pin is securely tightened with respect to the nut without the need for tools. The hitch pin secures the shank tube tightly against the receiver tube to minimize any relative movement between the shank tube and receiver tube.  
         [0015]     In a preferred embodiment of the present invention the hitch pin includes a locking handle that is pivotable relative to the hitch pin. The locking handle includes cam surface so that as it is pivoted downward, the cam surface forces the shank tube nut against the shank tube which in turn forces the shank tube against the receiver tube. This limits the relative movement between the shank tube and the receiver tube.  
         [0016]     The present invention in a preferred embodiment uses a resilient member with the locking handle. The resilient member may be a spring, an elastomer bushing, an elastomer shank tube nut, an elastomer cam surface on the locking handle or any other type of resilient member that enables the cam surface to tighten the shank tube nut against the shank tube.  
         [0017]     The locking handle of a preferred embodiment of the present invention includes a telescoping handle portion. This provides additional leverage for tightening the hitch pin relative the shank tube nut as well as for engaging and locking the handle cam surface relative to the hitch pin.  
         [0018]     These and other features will be evident from the ensuing detailed descriptions of preferred embodiment and from the drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1  is a perspective view of a receiver mounted accessory system.  
         [0020]      FIG. 2  is a perspective view of a preferred embodiment of the hitch pin securing system of the present invention.  
         [0021]      FIG. 3  is a side view of the embodiment of  FIG. 2  in the unlocked position.  
         [0022]      FIG. 4  is a side view of the embodiment of  FIG. 2  in the locked position.  
         [0023]      FIG. 5  is a cross-sectional view of the hitch pin securing system of  FIG. 1  and  FIG. 2 .  
         [0024]      FIG. 6  is a cross-sectional view of a different mounting of the hitch pin securing system of  FIG. 2 .  
         [0025]      FIG. 7  is a cross-sectional view of an alternative embodiment of the hitch pin securing system of the present invention.  
         [0026]      FIG. 8  is a cross-sectional view of a different mounting of the hitch pin securing system of  FIG. 7 .  
         [0027]      FIG. 9  is an alternative embodiment of the hitch pin securing system of the present invention.  
         [0028]      FIG. 10  is a different shank tube nut using the embodiment of  FIG. 2 .  
         [0029]      FIG. 11  is an alternative embodiment of the hitch pin securing system of the present invention.  
         [0030]      FIG. 12  is an alternative embodiment of the hitch pin securing system of the present invention.  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0031]     A preferred embodiment of the present invention is illustrated in  FIGS. 1-5 . 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.  
         [0032]     In the preferred embodiment, shown in  FIG. 1 , receiver hitch assembly  10  includes receiver tube  20  mounted beneath a bumper of a vehicle. Receiver tube  20  is mounted to the vehicle by well known mounting techniques, such as by bolting or welding. In this preferred embodiment, receiver tube  20  includes either 11/4 inch square tubing or 2 inch square tubing (internal dimensions). It is to be expressly understood that other sizes or shapes of tubing can be used as well.  
         [0033]     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 of the present invention may be used with any number of hitch pin assemblies. It is described for use with a spring nut hitch pin assembly, such as the hitch pin assemblies described in U.S. Pat. Nos. 6,945,550; 6,609,725 and 6,409,203, all of which are incorporated herein by reference. This description of those hitch pin assemblies are for descriptive purposes only and are not meant to limit the present invention.  
         [0034]     Shank tube  30 , as shown in  FIGS. 1 and 5 , includes a portion  32  having a shape similar to the shape of the internal portion  22  of receiver tube  20  and an external diameter slightly less than the internal diameter of the receiver tube  20 . This enables the shank tube  30  to be inserted within the receiver tube  20  in a telescoping manner. In most typical receiver hitch assemblies, the difference in the dimensions of the internal portion  22  of the receiver tube  22  and the external portion  32  of the shank tube  30  is about 1/16 inch (one-sixteenth inch) to allow the shank tube  30  to be easily inserted within the receiver tube  20 . In the exemplary embodiment described herein, shank tube  30  is illustrated as having a trailer hitch ball mounted thereon. It is to be expressly understood that the claimed inventions also include shank tubes having carriers mounted thereon, such as bicycle carriers, ski carriers, cargo compartments, platforms and other types of receiver mounted devices.  
         [0035]     As shown in  FIG. 5 , receiver tube  20  includes opposing side holes  24 ,  26 . The shank tube also includes opposing side holes  34 ,  36  that align with the opposing side holes  24 ,  26  of the receiver tube  20  as the shank tube  30  is inserted into the receiver tube  20 . Hitch pin assembly  40  is inserted through side holes  24 ,  26  of the receiver tube  20  and the side holes  34 ,  36  of the shank tube to secure the shank tube  30  to the receiver tube  20 .  
         [0036]     In a preferred embodiment, hitch pin assembly  40  includes pin  42 , shown in  FIG. 2 . Pin  42  includes a head portion  44  with reduced flat portions  46 ,  48 , an elongated portion  50 , a locking groove  52  and a tapered end  54 . Elongated portion  50  includes a threaded section  56  and a reduced diameter portion  58 . The threaded section  56  of elongated portion  50  is spaced a distance “d” from head portion  44 . This distance “d” preferably equal to or less than the combined thicknesses of the side walls of the receiver tube  20  and the shank tube  30 .  
         [0037]     Locking handle  60  is pivotally mounted on the hitch pin  42  by pin  62  extending through hole  64  on the locking handle through a hole formed in the head portion  44  of the hitch pin  42 . Slot  66  is formed in the locking handle  60  to fit over the reduced flat portions  46 ,  48  on the hitch pin. The locking handle  60  is thus able to rotate about the transverse axis of the hitch pin but does not rotate about the longitudinal axis of the hitch pin  42  as shown in  FIGS. 2-4 . The hole  64  on the locking handle is located slightly off center so that the distance d 1  between the surface  70  and the hole  64  is less than the distance d 2  between the surface  72  and hole  64  as shown in  FIGS. 3 and 4 . This creates a cam surface for cinching the hitch pin assembly tight as discussed in greater detail below. The end portion  68  of the locking handle  60  is reduced to create a handle surface for operating the locking handle.  
         [0038]     The hitch pin assembly also includes a resilient member  76  that is mounted onto the hitch pin  42 . In this preferred embodiment, the resilient member  76  is an elastomer spring, such as a polyurethane spring. It is to be expressly understood that other types of materials may be used as well. In this preferred embodiment, the resilient member  76  is mounted on the hitch pin  42  adjacent the locking handle  60  as shown in  FIG. 5 . The durometer of the resilient member can be selected in accordance with the need for more or less resilience, for the size of the member and for other reasons.  
         [0039]     Hitch pin assembly  40  also includes spring nut assembly  80 . Spring nut assembly  80  includes a square nut  82  having an internal threaded portion  84  for mating engagement with threaded section  56  of pin  42 . The outer dimension of the square nut  82  is selected to prevent the nut from rotating within the internal portion of the shank tube  30  as discussed below. Compression spring  86  is attached to one side of nut  82 . The compression spring  86  is sized so that it is in a state of compression when the spring nut assembly  80  is inserted within the shank tube  30  as discussed below.  
         [0040]     Another component of hitch pin assembly  40  is lock  90 . Lock  90  engages over the tapered end  54  of pin  42  and locks onto locking groove  52 .  
         [0041]     In use, spring nut assembly  80  is inserted within the internal cavity of shank tube  30 . Spring  86  is compressed so that spring nut  80  is able to be easily inserted into shank tube  30 . The spring nut is inserted into the shank tube  30  until the internal threaded portion  44  is aligned with side holes  34 ,  36  of the shank tube. Compression spring  86  resiliently presses between the inner side wall of the shank tube  30  and the nut  82  to maintain the alignment between the threaded portion  84  and the side holes  34 ,  36 .  
         [0042]     It is to be expressly understood that while compression spring  86  is discussed in the exemplary embodiment for descriptive purposes, other resilient mechanisms can be used as well to maintain the alignment between the nut  80  and the side holes  34 ,  36 . For example, an elastomer body could be used in lieu of the spring  86 . Also, in another embodiment, nut  86  can be affixed either permanently or temporarily on the interior of the shank tube by welding, by adhesive or by other known mechanisms. Also, the side hole  34  could be threaded instead of using a separate nut. In another embodiment, an alignment member, such as a detent member, notch, or other member can be incorporated in either the nut or the shank tube to align the nut with the side holes. The spring nut assembly of the present invention also includes other shank tube nut alignment systems that align the nut within the shank tube, such as the nut tube holder  130  shown in  FIG. 10 .  
         [0043]     Shank tube  30  is then ready for insertion into the receiver tube  20  once the spring nut assembly  80  has been installed within the shank tube  30 . Shank tube  30  is “telescoped” within the receiver tube  20  until the side holes  34 ,  36  are aligned with the side holes  24 ,  26  of the receiver tube. Pin  42  is then inserted into the side holes  24 ,  34  until the threaded portion  56  of the pin  42  engages the threaded portion  84  of the spring nut assembly  60 . Pin  42  is then rotated relative to the nut  82  to tighten the nut  82  against the inner side wall of the shank tube  30 . The locking handle  60  in a vertical or partially vertical orientation is used to provide leverage to easily rotate the pin relative to the nut. The size of the nut  82  is selected to ensure that the nut cannot rotate within the shank tube  30 . As the pin  42  continues to be rotated relative to nut  82 , nut  82  exerts pressure against the inner side wall of the shank tube  30  which in turns clamps against the inner side wall of the receiver tube  20 .  
         [0044]     Once the pin and nut are snug against the shank tube and receiver tube, the locking handle is then rotated downward into a horizontal position so that surface  72  engages the resilient member  76 . The increased distance d 2  on the locking handle  60  exerts additional pressure on the resilient member  76  to further tighten the shank tube against the receiver tube so that relative movement between the shank tube  30  and the receiver tube  20  is minimized or even eliminated. Thus the rattling of the shank tube and associated trailer or carrier mounts is minimized. Wear between the shank tube and receiver tube is also minimized as well. The use of cam surface on the locking handle provides a secure locking mechanism without the need of wrenches or other tools that are often not available. The pressure can be reduced on the resilient member  76  by pivoting the locking handle upward and then simply rotating the handle and pin to remove the pin from the nut.  
         [0045]     Lock  90  can then be secured and locked onto the end  54  of the pin assembly  40  to prevent unauthorized removal of the pin assembly  40  and the shank tube  30 . In another preferred embodiment, pin  42  includes a groove to allow 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  42  from the shank tube  30  and receiver tube  20 .  
         [0046]     In another alternative embodiment, bushing  100  can be provided to go over the elongated portion  46  of pin  42 . Bushing  100  butts up against the shoulder of threaded portion  48  of the pin to ensure that the pin  42  fits tightly within the side holes  26  of the receiver tube and  36  of the shank tube. Also, the lock  90  will engage the bushing as well to ensure a tight fit between the components.  
         [0047]     In another preferred embodiment of the present invention, the resilient member  70  is inserted between the spring nut  82  and the inner surface of the shank tube as shown in  FIG. 6 . The hitch pin  42  is inserted through the side holes of the receiver tube and the shank tube and through the resilient member  76  where it engages the threaded portion of the nut  82 . Once the hitch pin  42  and nut  82  are snug against the surfaces of the receiver tube and shank tube respectively, the locking handle  60  is rotated downward causing the cam surface  72  to engage the receiver tube to compress the nut  82  against the resilient member  76  to secure the shank tube against the receiver tube and minimize the rattling and movement of the shank tube relative to the receiver tube.  
         [0048]     Another preferred embodiment of the present invention is illustrated in  FIG. 7 . This embodiment is similar to the above described embodiment except a coil spring  110  is used as the resilient member  76 . A washer  112  is provided between the coil spring  110  and locking handle  60 . The operation of this embodiment is identical to the earlier described embodiments. Once the hitch pin  42  is threaded into the nut  82  and the receiver tube and shank tube are snug against one another, the locking handle is rotated downward into a horizontal position. This causes the surface  72  to engage against the washer and coil spring to provide additional pressure between the receiver tube and shank tube to minimize movement between the receiver tube and shank tube.  
         [0049]     Another preferred embodiment is illustrated in  FIG. 8 . This embodiment inserts the coil spring  110  between the nut  82  and the inner surface of the shank tube. Once the hitch pin  42  is threaded into the nut  82  and the receiver tube and shank tube are snug against one another, the locking handle is rotated downward into a horizontal position. This causes the surface  72  to engage against the receiver tube to provide additional pressure between the receiver tube and shank tube to minimize movement between the receiver tube and shank tube.  
         [0050]     Another preferred embodiment is illustrated in  FIG. 9 . This embodiment provides a fine threaded portion  120  on the hitch pin  42 . This threaded portion engages in a threaded portion on pin  62 . This allows a micro adjustment on spacing between the threaded portion  56  on hitch pin  42  and the locking handle  60 . This adjustment allows adjustment for the necessary force between the resilient member  76  and the locking handle. Different receivers and shanks have different tolerances, thus an adjustment may be necessary in order to achieve a tight fit using the present invention.  
         [0051]     The present invention, in another preferred embodiment, uses a hitch pin assembly similar to the above described embodiments. The nut  82  is embedded within an elastomer body that provides resilience as the locking handle is rotated downward. Alternatively, a threaded bushing embedded within an elastomer body may be used in lieu of the nut  82 . The resilient member  76  is eliminated in these embodiments.  
         [0052]     Another preferred embodiment of the present invention provides an elastomer portion on the cam surface  72  on the locking handle. This provides the resilience when the locking handle  60  is rotated downward so that resilient member  76  is not necessary.  
         [0053]     The present invention in another preferred embodiment is illustrated in  FIG. 11 . This hitch pin assembly  120  is similar to the above described embodiments with a hitch pin  122  having a head portion  124 , a threaded portion  126 , a reduced diameter portion  128 , a groove  130 , a tapered end portion  132 , resilient member  134  and a locking handle  140 . The locking handle  140  includes a telescoping handle  142  that provides additional leverage if needed for tightening the pin in the nut  82  and for locking the handle downward. The handle can be telescoped together to reduce the length once the handle is in the locked horizontal position.  
         [0054]     Another preferred embodiment is illustrated in  FIG. 12 . This hitch pin assembly  150  is similar to the above described embodiments with a hitch pin  152 , a head portion  154 , a threaded portion  156 , a reduced diameter portion  158 , a groove  160 , a tapered end portion  162 , a resilient member  164  and a locking handle  170 . The head portion  154  on this embodiment is spherical as shown in  FIG. 11 . The locking handle  170  includes a plurality of slots  172  with a concave inner portion that engages the spherical head portion  154 . The handle  170  has a plurality of circular cam surfaces  174  as well. The handle  170  also includes a telescoping handle  176  for additional leverage. The spherical head portion and multiple cam surfaces  174  provide additional cam surfaces for engaging against the resilient member  164  or the receiver tube to tighten the shank tube against the receiver tube.  
         [0055]     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 that utilize a cam locking handle that provides a tightening mechanism for rotating the pin relative to the shank nut as well as for locking the shank tube against the receiver tube.