Abstract:
A one-piece pintle hitch is disclosed. The one-piece hitch utilizes an integral drawbar that may be engaged with a conventional receiver assembly such as installed along the underside of a vehicle. The one-piece pintle hitch avoids the use of prior art mounting plates that bolt to one another. Accordingly, the problems associated with threaded fasteners such as loosening, fracturing, and corrosion, are eliminated. In addition, the one-piece pintle hitch utilizes a unique configuration along its bar portion that results in a significant reduction in weight and materials.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]    This application claims priority from a U.S. Provisional Application Serial No. 60/077,028, filed Mar. 6, 1998, entitled, “One-Piece Pintle Hitch.” 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to a one-piece pintle hitch assembly. Conventional pintle hitches utilize a flange or mounting plate, usually integral with a hitch, that is bolted or otherwise secured to another mounting plate on a vehicle or towbar assembly. The present invention provides a one-piece hitch assembly that avoids the necessity of providing mounting plates. In addition, the pintle hitch assembly of the present invention provides an improved design that provides significant advantages over currently known pintle hitch assemblies.  
           [0004]    2. Description of Related Art  
           [0005]    Pintle hitch assemblies are known in the art. For example, U.S. Pat. Nos. 5,332,250 to Thornwall et al.; 4,568,098 to Landrey Jr.; and 5,106,114 to Haupt, all of which are herein incorporated by reference, disclose various pintle hitch assemblies. However, all of these pintle hitch assemblies utilize a mounting plate that must be attached to a corresponding mounting plate on the tow vehicle. Typically, the plates are bolted to one another to secure the pintle hitch to the vehicle. It is cumbersome and burdensome to align and bolt or otherwise attach the mounting plate of the pintle hitch assembly to a mounting plate that has been previously installed on the vehicle, and/or to remove and unbolt the hitch assembly from the vehicle mounting plate. And, as will be appreciated, it is often difficult to install a mounting plate to the vehicle since the plate must be securely affixed to the vehicle frame. Accordingly, there is a need for a pintle hitch assembly that avoids the use of mounting plates and the problems associated with such plates.  
           [0006]    Moreover, there are significant safety concerns relating to the use of currently available pintle hitch assemblies that utilize mounting plates which bolt to one another. There are hazards associated with the use of bolts or threaded fasteners. Bolts are susceptible to being under torqued during installation which may lead to the bolt(s) becoming loose, and eventually separating from the assembly. Also, bolts may fracture or otherwise fail. And, it is well known that the threads and/or the corresponding threaded fastener, i.e., the nut, may become corroded and rust, thereby further increasing the difficulty of removing and re-attaching a pintle hitch to the tow vehicle. As a result, there is a need for a pintle hitch assembly that is not susceptible to these types of safety concerns.  
           [0007]    Currently known pintle hitch assemblies are relatively heavy in view of the significant amount of metal used to form the bar portion of the assembly. The resulting weight increases the difficulty in mounting the pintle hitch assembly to the vehicle, and further increases costs associated with the manufacture of such assembly, primarily due to the increase in the amount of materials that are necessary. Accordingly, there is a need for an improved pintle hitch assembly, one which is lighter in weight and which is less expensive to manufacture.  
         SUMMARY OF THE INVENTION  
         [0008]    The present invention achieves all of the foregoing objectives and provides, in a first aspect, a pintle hitch comprising a bar and a lower jaw that is integral with an end of the jaw. The pintle hitch further comprises an upper jaw hingedly attached to the bar end at which is disposed the lower jaw. The upper jaw is movable between a closed position and an open position. The other end of the bar, opposite the end at which is disposed the lower jaw, is adapted to engage a receiver assembly. The use of conventional mounting plates and associated threaded fasteners is entirely avoided.  
           [0009]    In another aspect, the present invention provides a pintle hitch comprising a longitudinal bar member and a pintle hook and latch assembly disposed at an end of the bar. The bar defines two oppositely directed, narrowed regions along the side of the bar. The resulting pintle hitch is relatively light in weight and more economical to manufacture than conventional pintle hitches. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is an elevational view of a first preferred embodiment of the pintle hitch assembly according to the present invention.  
         [0011]    [0011]FIG. 2 is a top view of the first preferred embodiment pintle hitch assembly according to the present invention, the assembly having an upper latch component removed.  
         [0012]    [0012]FIG. 3 is an elevational view of a partially disassembled first preferred embodiment pintle hitch assembly, the assembly having a latch component removed.  
         [0013]    [0013]FIG. 4 is a cross-sectional view of the first preferred embodiment pintle hitch assembly shown in FIG. 3, the cross-section taken across line IV-IV in FIG. 3.  
         [0014]    [0014]FIG. 5 is an elevational view of a second preferred embodiment pintle hitch assembly according to the present invention.  
         [0015]    [0015]FIG. 6 is an elevational view of a third preferred embodiment pintle hitch assembly according to the present invention.  
         [0016]    [0016]FIG. 7 is an elevational view of a fourth preferred embodiment pintle hitch assembly according to the present invention in which the latch component has been removed.  
         [0017]    [0017]FIG. 8 is a top view of the fourth preferred embodiment pintle hitch assembly illustrated in FIG. 7.  
         [0018]    [0018]FIG. 9 is an elevational view of a fifth preferred embodiment pintle hitch assembly according to the present invention.  
         [0019]    [0019]FIG. 10 is an elevational view of a sixth preferred embodiment pintle hitch assembly according to the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]    The present invention provides a one-piece pintle hitch assembly. Conventional pintle hitches utilize a flange or mounting plate, usually integral with the hitch, that is bolted or otherwise secured to another mounting plate on a vehicle or towbar assembly. The present invention provides a one-piece hitch assembly that avoids the necessity of providing mounting plates and the requisite mechanical fasteners such as threaded bolts and nuts. The pintle hitch assembly of the present invention includes a pintle hook that is formed or otherwise integrally attached at the end of a drawbar or other member. The drawbar may be engaged with a vehicle or conventional hitch assembly. Preferably, the drawbar and pintle hook assembly of the present invention may be received in a conventional square or round receiver tube. Typical receivers include Class II receivers available from Draw-Tite™. Accordingly, the term “receiver” or “receiver assembly” as used herein refers to these and similar assemblies that receive, and are engageable with, a drawbar.  
         [0021]    In another aspect, the present invention provides a unique cross-sectional configuration utilized along one or more regions of the bar component of the preferred embodiment pintle hitch assembly. The unique configuration reduces the amount of material otherwise necessary, and thus, the weight of the assembly.  
         [0022]    In yet another aspect, the present invention assembly provides a bar member in which the end of the bar, at which is located the pintle hitch, is offset from the longitudinal axis of the remaining portion of the bar. The present invention provides other preferred versions and configurations described herein.  
         [0023]    Generally, the present invention relates to a one-piece pintle hitch that installs in conventional square or round receiver tubes. This one-piece hitch incorporates an upper hinged jaw or latch as generally referred to herein, a jaw locking device and a lower hook or jaw, and/or a combination ball lower jaw. The one-piece hitch preferably utilizes a bar having a square, rectangular, or circular cross section that is sized to fit common receivers. The device can be produced by welding, casting, or forging of iron, steel, etc. All of these aspects are described in greater detail below.  
         [0024]    Referring to FIGS.  1 - 4 , a first preferred embodiment pintle hitch assembly  1  according to the present invention is illustrated. It is to be understood that the referenced drawings are not to scale. In most applications, the bar portion of the pintle assembly will be significantly longer than shown. The pintle assembly  1  comprises a longitudinal bar  2 , a lower hook or jaw  50 , and a neck  30  extending between the hook  50  and the bar  2 . The bar defines an aperture  4  proximate or near a bar end  20  as shown. The aperture  4  serves to receive a pin (not shown) that extends through the aperture  4  when the assembly  1  is engaged to the vehicle, i.e. a tow bar receiver typically installed along the rear underside of the vehicle. The bar  2  further defines a medial narrowed region  6  extending between the aperture  4  and the neck  30 . Preferably, the bar  2  defines two narrowed regions  6 , each on opposite sides of the bar  2 . Each narrowed region  6  is defined by a recessed surface  10  and a transition surface  8  extending around the recessed surface  10 . The bar  2  further defines a distal narrow regioned  12  generally located between the aperture  4  and the bar end  20 . Preferably the bar  2  defines two narrowed regions  12 , each on opposite sides of the bar  2 . Each distal narrow regioned  12  defines a transition surface  14  that extends around a recessed surface  16 . The narrowed regions  6  and  12  are described in greater detail in conjunction with FIG. 2. The bar  2  has a bar outer surface  22  as shown.  
         [0025]    The neck  30  generally provides a transition region that connects the bar  2  and the hook  50 . The neck  30  comprises an upper and a lower strengthening member  34  and  36 , respectively, and an intermediate connecting portion  32  extending between the members  34  and  36 .  
         [0026]    The hook  50  generally comprises an arcuate member for engaging a conventional pintle eye component as known in the art. The arcuate member is generally C-shaped or in the shape of a semi-circle as shown in FIG. 1. The hook  50  includes an inner engagement surface  52  and a latch contact surface  54 .  
         [0027]    Referring to FIG. 1, the pintle assembly  1  further comprises an upper hinged jaw or latch  40  pivotally attached to a portion of the hook  50  or the neck  30 . The latch  40  is preferably pivotally attached by use of a pivot member  60  which serves as an axis for pivoting of the latch  40 . An aperture (not shown) is preferably defined in the latch  40  that serves to receive the pivot member  60 . An aperture  62  is also preferably provided in a region of the hook  50  or neck  30  for receiving the pivot member  60 . That member  60  preferably extends through or at least into both the aperture  62  in the hook  50  or the neck  30 , and the aperture defined in the latch  40 . The latch  40  further defines an aperture  46  along its mid-section. The aperture  46  is used in conjunction with a pin (not shown) that is used to provide a jaw locking arrangement. This is described in greater detail below. The latch  40  also includes an inner engagement surface  42  opposite the inner engagement surface  52  of the hook  50 . Also defined along the outer end of the latch  40  is a hook contact surface  44  which opposes and contacts the latch contact surface  54  of the hook  50 . As will be understood, the latch  40  preferably pivots about the pivot member  60  from a closed position, in which the contact surfaces  44  and  54  contact, or at least substantially so, each other, to an open position in which the latch  40  is pivoted upward thereby providing an opening between the surfaces  44  and  54 , the opening being sufficient to receive a pintle eye component for subsequent engagement with the hook  50 . As will be understood, once the latch  40  is in its closed position, it may be locked in that position by use of the jaw locking arrangement comprising a pin that is inserted in the aperture  46 . Other locking arrangements may be utilized.  
         [0028]    [0028]FIG. 2 is a top view of the first preferred embodiment pintle hitch assembly, illustrating in greater detail the preferred configuration of the narrowed regions  6  and  12 . FIG. 2 illustrates the hitch assembly  1  having the upper latch  40  removed. It can be seen that each of two sides of the bar  2  defines a narrowed region  6  and another narrowed region  12 . The regions  6  and  12  are separated by the aperture  4 . The narrowed regions  6  on opposite sides of the bar  2  are preferably co-extensive with each other as shown in FIG. 2. Similarly, the narrowed regions  12  on opposite sides of the bar  2  are also coextensive with each other.  
         [0029]    Referring to FIGS. 2 and 4, as noted, each narrowed region  6  includes a recessed surface  10  and a transition surface  8  that bounds the perimeter of the recessed surface  10  and which generally extends between the recessed surface  10  and the outer surface  22  of the bar  2 . As will be understood, FIG. 4 is a cross-sectioned view of the bar  2  taken along line IV-IV in FIG. 3. Each of the recessed surfaces  10  are preferably parallel to each other and also parallel to the longitudinal axis of the bar  2 . The transition surface  8  preferably extends at an angle other than 90° to the recessed surface  10  and the outer surface  22  of the bar  2 . Most preferably, the angle between the recessed surface  10  and the transition surface  8  is from about 100° to about 135°. It is also preferred that the region of intersection between the recessed surface  10  and the transition surface  8  be rounded and smoothed to minimized the tendency for dirt and other debris to collect therein.  
         [0030]    Referring further to FIGS. 2 and 4, as noted, each narrowed region  12  includes a recessed surface  16  and a transition surface  14  that bounds the perimeter of the recessed surface  16  and which generally extends between the recessed surface  16  and the outer surface  22  of the bar  2 . Each of the recessed surfaces  16  is preferably parallel to each other and also parallel to the longitudinal axis of the bar  2 . The transition surface  14  preferably extends at an angle other than 90° with respect to the recessed surface  16  and the outer surface  22  of the bar  2 . Most preferably, the angle between the recessed surface  16  and the transition surface  14  is from about 100° to about 135°. As previously explained, it is also preferred that the region of intersection between the recessed surface  16  and the transition surface  14  be rounded and smoothed.  
         [0031]    [0031]FIG. 3 illustrates the preferred embodiment pintle hitch assembly  1 , partially disassembled, having the latch  40  and pivot member  60  removed. Aperture  62  is defined in an upper portion of the region extending between the hook  50  and the neck  30 . The aperture  62  is sized to receive the pivot member  60  for securing the latch  40  to the remainder of the assembly  1  and for enabling the latch  40  to be pivoted about the member  60 .  
         [0032]    Referring to FIG. 5, a second preferred embodiment pintle hitch assembly  100  according to the present invention is illustrated. The pintle assembly  100  comprises a longitudinal bar  102 , a hook  150 , and a neck  130  extending between the hook  150  and the bar  102 . The bar defines an aperture  104  proximate or near a bar end  120  as shown. The bar  102  has a bar surface  122  as shown.  
         [0033]    The neck  130  generally provides a transition for connecting the portion between the bar  102  and the hook  150 . The neck  130  comprises upper and lower strengthening members  134  and  136 , respectively, and an intermediate connecting portion  132 .  
         [0034]    The hook  150 , generally comprises an arcuate member for engaging a conventional pintle eye component as known in the art The hook  150  includes an inner engagement surface  152  and a latch contact surface  154 .  
         [0035]    The pintle assembly  100  further comprises a latch  140  pivotally attached to a portion of the hook  150  or the neck  130  as shown. The latch  140  is preferably pivotally attached by use of a pivot member  160  which serves as the axis for pivoting of the latch  140 . The latch  140  further defines an aperture  146  along its mid-section. As previously explained, the aperture  146  is used in conjunction with a pin (not shown) to lock or secure the latch in a closed position. The latch  140  also includes an inner engagement surface  142  opposite the inner engagement surface  152  of the hook  150 . Also defined along the outer end of the latch  140  is a hook contact surface  144  which opposes and contacts the latch contact surface  154  of the hook  150 .  
         [0036]    It is to be understood that all of the preferred embodiment pintle hitch assemblies described herein may be formed in a variety of ways, including welding. If welding is employed, a pintle hook and latch sub-assembly may be welded to a bar along a ridge  170  as shown in FIG. 5. It is also to be understood that the present invention one-piece pintle hitch assemblies may, in some applications, not utilize one or more narrowed regions, such as the previously described narrowed regions  6  and  12 . The second preferred embodiment  100  is illustrated as being devoid of any narrowed regions along its bar  102 .  
         [0037]    Referring to FIG. 6, a third preferred embodiment pintle hitch assembly  200  according to the present invention is illustrated. The pintle hitch assembly  200  comprises a longitudinal bar  202 , a hook  250  and a neck  230  extending between the hook  250  and the bar  202 . The bar defines an aperture  204  proximate or near a bar end  220  as shown. The bar  202  has a bar surface  222  and a bar end  220  as shown.  
         [0038]    The neck  230  generally provides a transition for connecting the portion between the bar  202  and the hook  250 . The neck  230  comprises upper and lower strengthening members  234  and  236 , respectively, and an intermediate connecting portion  232 .  
         [0039]    This preferred embodiment  200  utilizes a combination ball lower jaw. Specifically, the hook  250  generally comprises a base  282  disposed at a distal end of the hook  250 . Projecting upward from the base  282  is a ball  280 . The ball  280  is preferably sized to be engageably received in a conventional socket housing. The hook  250  further includes an inner engagement surface  252 .  
         [0040]    The pintle hook assembly  200  further comprises a latch  240  pivotally attached to the portion of hook  250  or neck  230 . The latch  240  is preferably pivotally attached by use of a pivot member  260  which serves as the axis for pivoting of the latch  240 . The latch  240  further defines an aperture  246  along its mid-section. The latch  240  also includes an inner engagement surface  242  opposite the inner engagement surface  252  of the hook  250 . Also defined along the outer end of the latch  240  is an inner contact surface  244  which opposes and contacts, or at least substantially so, the ball  280  of the hook  250 .  
         [0041]    Referring to FIGS. 7 and 8, a fourth preferred embodiment pintle hitch assembly  300  according to the present invention is illustrated. The pintle hitch assembly  300  comprises a longitudinal bar  302 , a hook  350 , and a neck  330  extending between the hook  350  and the bar  302 . The bar defines an aperture  304  proximate or near a bar end  320  as shown. The bar  302  further defines a first and second medial narrowed region  306  and  306   a  extending between the aperture  304  and the neck  330 . Preferably, the narrowed regions  306  and  306   a  are defined on two oppositely directed faces of the bar  302 . Each narrowed region  306  and  306   a  is defined by a recessed surface  310  or  310   a  and a transition surface  308  or  308   a  extending around the recessed surface  310  or  310   a . The bar  302  further defines a distal narrowed regioned  312  generally located between the aperture  304  and the bar end  320 . The distal narrowed regioned  312  defines a transition surface  314  that extends around a recessed surface  316 . The bar  302  has a bar surface  322  as shown.  
         [0042]    The neck  330  generally provides a transition region for connecting the portion between the bar  302  and the hook  350 . The neck  330  comprises an upper and a lower strengthening member  334  and  336 , respectively, and an intermediate connecting portion  332 .  
         [0043]    The hook  350  generally comprises an arcuate member for engaging a conventional pintle eye component as known in the art. The hook  350  includes an inner engagement surface  352  and a latch contact surface  354 .  
         [0044]    The pintle assembly  300  further comprises a latch (not shown) pivotally attached to the region of hook  350  or neck  330 . Although the latch is not shown in FIGS. 7 and 8, it will be understood that the latch resembles and generally corresponds to any of the previously described latches  40 ,  140 , and  240 . The latch is preferably pivotally attached by use of a pivot member (not shown) which serves as the axis for pivoting of the latch. An aperture  362  is defined in an upper portion of the region between the hook  350  and the neck  330 . The aperture  362  is sized to receive the pivot member.  
         [0045]    The distal narrowed region  312  generally corresponds to the previously described distal narrowed region  12  in the preferred embodiment pintle hitch assembly  1 . Each of the medial narrowed regions  306  and  306   a  generally correspond to the previously described medial narrowed region  6  in the preferred embodiment pintle hitch assembly  1 .  
         [0046]    Referring to FIG. 9, a fifth preferred embodiment pintle hitch assembly  400  according to the present invention is illustrated. This embodiment finds particular use in applications in which the tow vehicle is at a lower elevation than the trailer or pintle eye. The pintle hitch assembly  400  comprises a longitudinal bar  402 , a hook  450 , a neck  430 , and an upward extension portion  470  extending between the hook  450  and neck  430 , and the bar  402 . The bar defines an aperture  404  proximate or near a bar end  420  as shown. The bar  402  further defines a medial narrowed region  406  extending between the aperture  404  and the extension portion  470 . The narrowed region  406  is defined by a recessed surface  410  and a transition surface  408  extending around the recessed surface  410 . The bar  402  further defines a distal narrowed region  412  generally located between the aperture  404  and the bar end  420 . The distal narrowed region  412  defines a transition surface  414  that extends around a recessed surface  416 . The bar  402  has a bar outer surface  422  as shown.  
         [0047]    The neck  430  generally provides a transition for connecting the portion between the bar  402  and the hook  450 . The neck  430  comprises upper and lower strengthening members  434  and  436 , respectively, and an intermediate connecting portion  432  extending therebetween.  
         [0048]    The hook  450  generally comprises an arcuate member for engaging a conventional pintle eye component as known in the art. The hook  450  includes an inner engagement surface  452  and a latch contact surface  454 .  
         [0049]    The pintle assembly  400  further comprises a latch (not shown) pivotally attached to a portion of hook  450  or neck  430 . Although the latch is not shown in FIG. 9, it will be understood that the latch resembles and generally corresponds to any of the previously described latches  40 , 140 , and  240 . The latch is preferably pivotally attached by use of a pivot member (not shown) that extends through an aperture  462  which serves as the axis of pivoting of the latch.  
         [0050]    Referring to FIG. 10, a sixth preferred embodiment pintle hitch assembly  500  according to the present invention is illustrated. This embodiment finds particular use in applications in which the tow vehicle is at a higher elevation than the trailer or pintle eye. The pintle hitch assembly  500  comprises a longitudinal bar  502 , a hook  550 , a neck  530 , and a downward extension portion  570  extending between the hook  550  and the bar  502 . The bar defines an aperture  504  proximate or near a bar end  520  as shown. The bar  502  further defines a medial narrowed region  506  extending between the aperture  504  and the portion  570 . The narrowed region  506  is defined by a recessed surface  510  and a transition surface  508  extending around the recessed surface  510 . The bar  502  further defines a distal narrowed regioned  512  generally located between the aperture  504  and the bar end  520 . The distal narrowed region  512  defines a transition surface  514  that extends around a recessed surface  516 . The bar  502  has a bar outer surface  522  as shown.  
         [0051]    The neck  530  generally provides a transition for connecting the portion between the downward extension portion  570  and the hook  550 . The neck  530  comprises an upper and a lower strengthening member  534  and  536 , respectively, and an intermediate connecting portion  532 .  
         [0052]    The hook  550 , generally comprises an arcuate member for engaging a conventional pintle eye component as known in the art. The hook  550  includes an inner engagement surface  552  and a latch contact surface  554 .  
         [0053]    The pintle assembly  500  further comprises a latch (not shown) pivotally attached to the portion of hook  550  or neck  530 . The latch is preferably pivotally attached by use of a pivot member (not shown) that extends through an aperture  562  which serves as the axis of pivoting of the latch. Although the latch is not shown in FIG. 10, it will be understood that the latch resembles and generally corresponds to any of the previously described latches  40 ,  140 , and  240 .  
         [0054]    It is also to be understood that one or more features of each of the previously described preferred embodiments 1, 100, 200, 300, 400, and 500, may be combined with one or more other features of the noted preferred embodiments.  
         [0055]    The various preferred embodiment pintle hitch assemblies replace conventional two-piece pintle hook or combination hook, and pintle mount adapters. These preferred embodiments offer savings in weight, installation, time and cost.  
         [0056]    Specifically, the unique configuration of the narrowed regions described herein, when provided in the bar portion of the present invention hitch assembly, significantly reduces the weight of the final assembly without sacrificing strength, safety, or reliability. The preferred embodiment hitch assemblies described herein are about 35% lighter in weight as compared to competing two-piece hitch assemblies that do not utilize narrowed portions, and that employ mounting plates. As previously noted, the narrowed regions result in significant savings in material and time and labor otherwise necessary to carry out the requisite machining and forming. Another important feature of the present invention one-piece hitch assembly is that it is more compact and easier to stow than a corresponding hitch assembly utilizing mounting plates and threaded fasteners.  
         [0057]    The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon a reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof.