Abstract:
A hitch assembly for connecting a towed vehicle to a towing vehicle include a housing mounted on the towing tongue of the towed vehicle having a tow bar mounted in an internal cavity having a restricted throat. Tow bar can be extended and pivoted to position a hitching eyelet on a variably proximately located towed vehicle. The tow arm coacts with the walls of the cavity to provide a torque on the tongue upon forward or rearward movement of the towing vehicle. Upon rearward movement of the towed vehicle, the tow bar attains an aligned nested position in the cavity and a lock assembly is actuated for locking the tow arm to the housing.

Description:
RELATED APPLICATION 
   This application is a continuation-in-part of U.S. application Ser. No. 10/628,064, filed Jul. 25, 2003 now abandoned, which claims the benefit of U.S. Provisional Application No. 60/398,757, filed Jul. 26, 2002, both in the of Thomas M. Williams, Jr. and entitled “Telescoping and Swiveling Hitch Assembly”. 

   FIELD OF THE INVENTION 
   The present invention relates to coupling systems for releasably interconnecting a towing vehicle with a towed vehicle and, in particular, a telescoping and swiveling hitch assembly for enabling coupling between proximately located vehicles. 
   BACKGROUND OF THE INVENTION 
   Powered and trailed vehicles are conventionally interconnected for travel by coupling hitches involving fixed locations on the vehicles. Using ball and socket type universal connections or pin type connections the required relative movement during travel is provided. The fixed locations, however, are difficult to effect particularly with large vehicle that prevent ready manual alignment for final coupling. When accurate alignment is not obtained, the towed vehicle is manually moved to proper position, requiring strength, dexterity and multiple personnel, often with an attendant risk of injury. As the tongue weight of the towed vehicle increases the skills and risks are substantially increased. The problem is particularly troublesome for large steerable wheel trailers, such as employed by the military. 
   Telescoping and pivoting hitches have been proposed to allow coupling between misaligned vehicles. Most are designed for lighter weight trailers and unsuited for heavy load applications. Others provide only a length dependent articulation reducing the accommodated zone of vehicle misalignment. 
   For instance, U.S. Pat. No. 4,515,387 to Shuck utilizes a tongue that must be fully extended before tow bar can be pivoted, thereby restricting the permissible zone of vehicle misalignment. The hitch is formed of lightweight materials not suitable for heavy trailer applications. Further, the alignment torque during retraction is borne by a sliding pin connection further reducing the ability to handle heavier trailer units. U.S. Pat. No. 5,277,447 to Blaser also provides a telescoping hitch that is pivotal only in the fully extended position. 
   U.S. Pat. No. 5,011,176 to Eppinette discloses a telescoping arm having a pivoting outer end allowing coupling to a misaligned vehicle. The towing vehicle must be moved forwardly to align the arm sections, at which time a slidable collar is placed around the pivot connection to prevent pivoting. Thereafter, the towing vehicle reversed to shift the arm to a retracted locked towing position. The need for forward movement, which is not always possible or convenient, and the multiple manual steps for achieving final coupling are disadvantageous. 
   U.S. Pat. No. 5,322,315 to Carsten discloses a fixed pivot arm having a telescoping outer end mounted on the towing vehicle. After coupling, the towing vehicle must be moved forwardly for aligning and locking the pivoting arm and thereafter rearwardly for locking the telescoping arm. U.S. Pat. No. 6,357,779 to Mok et al. also provides a fixed pivot arm having a telescoping outer end that requires forward movement for vehicle alignment and rearward movement for retraction and locking. 
   U.S. Pat. No. 6,328,326 to Slatten discloses a hitch tongue that is slidably and pivotally supported on a housing for coupling misaligned vehicles. The tongue and housing have complementary camming surfaces for nested alignment in a locked position. The camming surfaces provide limited aligning torque precluding usage on heavier trailer applications. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention provides a hitch assembly suitable for heavy vehicle applications that may be readily deployed for final coupling by rough relative positioning of the vehicles. The hitch assembly comprises only two unitized subassemblies, a housing and a tow bar, that may be assembled, and disassembled for repair, using simple tools. In one aspect, the hitch assembly comprises: a housing member having an internal cavity with a restricted throat opening; an tow bar member extending into the cavity an having a tail section larger than the throat opening and establishing when engaged therewith a pivotal connection for forward aligning movement, the tow bar member being supported by said housing member for cojoint longitudinal and pivotal movement between a retracted coupled position and an extended alignment position; means for mounting the housing member on one of the vehicles; means for mounting a component of the coupling member on the tow bar member; and latching means permitting movement of the tow bar member between the coupled position and the alignment position in a unlatched condition and fixedly connecting the tow bar member to the housing member in a latched condition; and actuating means for selectively moving said latching means between said unlatched condition and said latched condition. 
   The cavity has a parabolic shape characterized by widely spaced sidewalls gradually sloping inwardly from the throat and merging with a rounded base. The configuration allows substantial articulation for entire range of extension as the tow arms horizontally floats within the cavity. According, a coupling zone is provided of relatively constant width and substantial length thereby accommodating a wide range of vehicle misalignments. While the vehicles may be aligned by initial forward movement of the towing vehicle, advantageously the towing vehicle may be directly reversed to effect alignment and coupling. During initial rearward movement, the tow arm freely moves until contacting the cavity wall. Thereafter, a substantial lever arm is established with the throat providing a substantial aligning torque on the trailer tongue. As the tow arm reaches the retracted position. Nesting surfaces on the tow bar and housing coact for effecting final alignment. Whereas current military and heavy load vehicles require multiple attempts for proper vehicle placement and multiple personnel for final positioning and coupling, the present invention provides a permissible preliminary alignment zone that can be readily achieved by the vehicle operator. Moreover, either the vehicle operator or a single ground personnel, can establish the hitch coupling, with final retraction and locking accomplished with a single rearward vehicle movement. 
   Accordingly, it is an object of the present invention to provide a hitch assembly for interconnecting vehicles that accommodates a wide range of vehicle misalignments. 
   Another object of the invention is to provide a telescoping and swiveling hitch assembly for interconnecting vehicles that reduces the time, effort and personnel required to couple misaligned vehicles. 
   A further object is to provide a adjustable position hitch assembly that provides a constant width and substantial length zone for accommodating attachment to proximately located vehicles. 

   
     DESCRIPTION OF THE DRAWINGS 
     The above and other objects and advantages of the invention will become apparent upon reading the following written description taken in conjunction with the accompanying drawings in which: 
       FIG. 1  is a perspective view of a truck and a trailer coupled with a hitch assembly in accordance with a preferred embodiment of the invention; 
       FIG. 2  is an enlarged perspective view of the hitch assembly in the coupled position with the truck; 
       FIG. 3  is a side view of the truck and trailer coupled with the hitch assembly; 
       FIG. 4  is a bottom perspective view of the hitch assembly in the extended and swiveled position at initial hookup with the truck; 
       FIG. 5  is a top perspective view of the hitch assembly in the extended and swiveled position; 
       FIG. 6  is a partially exploded perspective view of the hitch assembly; 
       FIG. 7  is a perspective view of the hitch assembly; 
       FIG. 8  is a horizontal cross sectional view of the hitch housing; 
       FIG. 9  is a partially sectioned perspective view of the hitch assembly in the locked position; and 
       FIG. 10  is a perspective view of the tow bar of the hitch assembly; 
       FIG. 11  is a left side perspective view of another embodiment of the hitch assembly; 
       FIG. 12  is a right side perspective view of the hitch assembly of  FIG. 11 ; 
       FIG. 13  is partially section front view through the loch assembly of the hitch assembly of  FIG. 11 ; 
       FIG. 14  is a top view of the hitch assembly of  FIG. 11 ; 
       FIG. 15  is a partially section side view of the hitch assembly of  FIG. 11 ; 
       FIG. 16  is a top view of the guide plate of the hitch assembly of  FIG. 11 ; 
       FIG. 17  is a top view of the hitch assembly of  FIG. 11  with the top plate removed; and 
       FIG. 18  is a side view of the hitch assembly of  FIG. 1  coupled to a hitch of a towing vehicle. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIGS. 1 through 5 , the present invention provides a telescoping and swiveling hitch assembly  10  for interconnecting a towing vehicle or truck  12  with a towed vehicle or trailer  14 . The hitch assembly  10  is particularly adapted for heavy-duty vehicles, such as military transport systems. An exemplary towing vehicle is a Medium Tactical Vehicle Replacement (MTVR) truck and a suitable towed vehicle is a Medium Tactical Vehicle Replacement Variant trailer, both manufactured by Oshkosh Truck Corporation of Oshkosh, Wis. As will become apparent, the hitch assembly may alternatively fixedly mounted on either vehicle and be releasably coupled with the other vehicle. The hitch assembly may be combined with conventional coupling configurations, such a ball and socket or pinned couplings, for accommodating relative articulating or universal movement between the vehicles. The hitch  16  on the truck  12  is conventional for MTVR truck/trailer combines and comprises a hook or pintle  18  surrounded by a protective shield  19 . 
   The trailer  14  includes a chassis  20  supported on front and real axle wheel assemblies  22 ,  23 . The front wheel assembly  22  is steerable. A trailer tongue  24  includes forwardly and inwardly converging side arms  26 . The side arms  26  are connected to the front wheel assembly  22  at horizontal pivot connections  28 . A cross bar  30  laterally interconnects the arms  26 . The front ends of the side arms  26  are laterally spaced whereby the side arms and the cross bar  30  form a forwardly opening generally triangular slot. In commercial units a tow bar assembly is removably connected at the forward end of the side arms at the slot entrance. In the present preferred embodiment the tow bar assembly is removed for direct reception, without further modification of the trailer, of the hitch assembly  10  and using a modification of the existing hitch eyelet. 
   Referring to  FIGS. 6 and 7 , the hitch assembly  10  comprises two subassemblies: a housing assembly  40  and a telescoping and swiveling tow bar or probe assembly  42 . The housing assembly includes a lock assembly  44 . As described in greater detail below, upon release of the lock assembly  44 , the probe assembly  42  has free horizontal movement and in combination with the pivoting of the trailer tongue  24  about the pivotal connections  28  permits the ready and safe coupling with a proximately located truck hitch. 
   The housing assembly  40  is hexagonal and configured to be received in the tongue slot of conventional MTVR trailers. The housing assembly  40  is welded or mechanically connected to the side arms  26  and cross beam  30 . 
   The housing assembly  40  comprises a hexagonal center guide block  46 , a removable triangular stop collar  48  assembled with fasteners  49 , a hexagonal top cover plate  50  and a hexagonal bottom cover plate  52 . Preferably, the plates  50 ,  52  are peripherally welded to the guide block  46  to provide a unitized assembly. A top reinforcing plate  53  is welded to the top cover plate  50  at the forward end thereof. A bottom reinforcing plate  55  is welded to the bottom cover plate  52  at the forward end thereof. 
   As shown in  FIG. 8 , the guide block  46  comprises a unitary body  54  having a generally U-shaped forwardly opening cavity  56 . The body  54  is exteriorly defined by forwardly inwardly converging front sidewalls  58 , rearwardly inwardly converging rear side walls  60 , a transverse rear wall  62  and a centrally vertically slotted front wall  64 . As discussed above, the front sidewalls  58  nest with the inner surfaces of the side arms  26  of the tongue, and the rear wall  62  engages the cross beam  30  whereat the housing assembly is welded or mechanically affixed. 
   The cavity  56  is defined by a continuous inner wall  68  in the longitudinal center of the body  54  and comprises a U-shaped, forwardly opening parabolic base and a pair of laterally spaced, apex opposed triangular sections  70 , one of which is the removable stop collar  48 . With the stop collar  48  assembled with the fasteners  49  establishing a constricted frontal throat opening  72  and frontally terminating with outwardly diverging planar guide surfaces  74 , forming a forwardly opening wedge shaped, tapered socket. Vertical through holes are drilled through the housing assembly and the stop collar  48  for the shanks of the fasteners  49  thereby providing for ready assembly and replacement of the collar  48 . A vertical bore  76  is formed through the longitudinal center of the housing assembly  40  and the lock assembly  44  forwardly of the opening  72  for reception of the lock bolt of the lock assembly  44 . 
   The lock assembly  44  includes a lock block  80 , a lock bolt  82  having an actuating handle  84  and spring biased downwardly by a compression spring  86 . The lock block  80  is a rectangular bar attached by welds to the top reinforcing plate  53  and centered over the vertical bore  76 . The lock block includes a bore extension concentric and complementary to the bore  76  and formed concurrently therewith. The lock bolt  82  is cylindrical and slidably supported in the bore  76 . An inverted J-slot  90  is formed in the sidewall of the lock block  80 . The inner end of the handle  84  extends through the slot  90  and connected in a counterbore in the side of the lock bolt  82 . When the handle  84  resides at the base of the slot  90 , the lock bolt  82  extends through the bore  76  to the bottom plates  52 ,  56  of the housing assembly  40  to establish a locked condition with the tow probe  42 . When the handle  84  is raised to the top of the slot  90  and rotated into the side notch  91  thereof, the lock bolt  82  is in an unlocked position with the lower end thereof above the guide block  46 . A cover plate  92  is connected to the top of the lock block by fasteners  94  thereby capturing and preloading the spring  88  against the top of the lock bolt  82 . 
   Referring additionally to  FIGS. 6 ,  9  and  10 , the tow probe  42  comprises an elongated tow bar  100  connected to a hitch eyelet  102  by threaded nut  104 . The tow bar  100  includes straight rectangular center section  106  narrower in width than the throat opening  72 , an enlarged circular tail section  108  and an enlarged head section  110 . When the tow bar  100  is in the fully retracted position, the tail section  108  engages the end wall of the housing cavity. When the tow bar  100  is in the fully extended position, the tail section  108  engages the walls of the collar sections  70  to establish a load bearing pivotal connection with the housing. 
   The head section  110  includes a base  112  having rearwardly inwardly inclined sidewalls  114  forming a tapered wedge adapted to conformally nest with the frontal walls  74  of the housing to center the tow probe  40  at and proximate to the retracted position. A through hole  116  is formed in the base  112  and is coaxial with the bore  76  in the housing to permit movement of the lock bolt between positions. 
   A vertical slot  120  is formed in the center of the head section. A longitudinal bore  122  is formed in the front end of the head section and intersects the slot  120 . The hitch eyelet  102  includes a cylindrical hook  130  having a vertical opening  132 , a base  134  rearwardly terminating with a threaded stud  136 . In assembly, the stud  136  is inserted through the hole  122  and the nut  104  threaded thereon to clamp the eyelet  102  to the probe head  110 . The assembled condition is maintained by a cotter pin  140  assembled in a conventional manner through radial slots and cross holes in the nut  104  and stud  136 , respectively. 
   It will be appreciated that the tow probe horizontally floats without fixed pivots within the confines of cavity to provide a wide zone of articulation throughout movement between the retracted and extended positions. This provides for a large strike zone for the eyelet to enable coupling with a proximately positioned pintle thereby obviating the need for tedious positioning of the towing vehicle and manual position of the trailer tongue. 
   As representatively shown in  FIGS. 4 and 5 , the vehicle  12  may be positioned at an angle with respect to the trailer and longitudinally separated, from a normal coupling position. To achieve coupling notwithstanding such misalignment, the handle  84  is raised in the slot  90  and rotated to the side notch  91  to provide a detented unlocked condition withdrawing the lock bolt from the tow arm. The tow probe  42  is then manually telescopically withdrawn and the eyelet  130  coupled with the pintle hook  18 . After withdrawal, the handle  84  may be releases thereby biasing the lock bolt  82  against the top surface of the center section  106   
   Final coupling may be accomplished in plural ways. In a direct method, the vehicle  12  may be directly backed toward the trailer. Before movement the latch handle  84  may be rotated into the slot and biased against the top surface of the tow probe. Rearward vehicle movement will drive the tow probe toward a retracted position whereat the cavity wall and opposed collar  70  are engaged thereby generating an aligning torque moving the tongue of the trailer toward longitudinal alignment with the tow bar. As the tow bar approaches the retracted position and the cavity wall become transverse to movement, the guide walls  114  of the head section  112  coact with the front walls  74  to provide a continuing aligning torque to accurately longitudinally align the tow probe in the cavity. When alignment is complete, the spring  88  biases the lock bolt through the opening  116  in the tow bar to effect without manual assistance the locked condition thereby permitting full transporting of the trailored vehicle  14 . 
   In the indirect method, the towing vehicle  12  is moved forwardly thereby fully extending the tow probe and establishing the load bearing pivotal connection at the collar with the tail section  108 . Further forward movement will establish an aligning torque on the tongue to longitudinally align the tow probe. When aligned the towing vehicle is backed until the tow probe is in the nested fully retracted position and the lock bolt actuated to the locked position. 
   The hitch assembly  10  may be integrated in various ways with the desired vehicle, for example by mechanical or welded attachment at the rear, or by integration into the towing tongue, or other suitable means. 
   Depending of the relative configuration of the housing components, a desired amount of extension and pivoting of the tow bar assembly can be provided. In actual use, a 30 inch extension with a 30 inch lateral swivel span has been successfully integrated into MTVR truck/trailer units. 
   Referring to  FIGS. 11 and 12 , there is illustrated another embodiment of the invention for use with lighter weight vehicles, such as trucks and automobiles. The hitch assembly  200  comprises two subassemblies: a housing assembly  202  and a telescoping and swiveling tow bar or probe assembly  204 . 
   The housing assembly  202  includes a lock assembly  206  having a rearwardly extending coupling arm  208  formed or rectangular tube. As shown in  FIG. 18 , the coupling arm  208  is telescopically removably coupled with a hitch box  210  and the towing vehicle by pin  214  inserted through transverse hole  219  in the coupling arm. The hitch box  210  is preferably a rectangular socket-type coupled commonly referred to a “Reese” hitch. The probe assembly  204  is provided with a ball member  216  for coupling with the hitch on the towed vehicle. As such, no further modification to the vehicle is necessary. It will, however, be apparent that the hitch may be mounted by other conventional methods to the selected vehicle. 
   As in the prior embodiment, the lock assembly  206  in the unlatched condition provides the probe assembly  204  with free horizontal and pivotal movement, which in combination with the pivoting of the trailer tongue on the towed vehicle permits the ready and safe coupling therebetween. 
   Referring to  FIGS. 13 through 15 , the housing assembly  200  comprises a rectangular center guide block  220 , a rectangular top cover plate  222  and a rectangular bottom cover plate  224 . Preferably, the plates  222 ,  224  are peripherally welded to the guide block  220  to provide a unitized assembly. A top reinforcing plate  226  is welded to the top cover plate  222  at the forward end thereof. A bottom reinforcing plate  228  is welded to the bottom cover plate  224  at the forward end thereof. 
   As shown in  FIG. 16 , the guide block  220  comprises a unitary body  230  having a base  232  and forwardly extending laterally spaced arms  234 . The inner surfaces of the base  232  and the arms  234  provide a generally U-shaped forwardly opening slot forming a cavity  236  in assembly. The cavity  236  is defined by a continuous inner wall comprising a U-shaped, forwardly opening parabolic base wall  238  and laterally spaced center walls  240 . The arms  234  frontally terminate with a pair of laterally spaced, apex opposed triangular collars  242 , one of which is the removable stop collar  222 . The stop collar  222  is removably assembled with the fasteners  244  ( FIG. 11 ). The inner tips of the triangular collars  222 ,  242  establish a constricted frontal throat. The collars  222 ,  242  have outwardly diverging planar front guide surfaces  246  and rear guide surfaces. The front guide surfaces  246  form, in assembly, a forwardly opening wedge shaped, tapered socket. Vertical through holes are drilled through the housing assembly  202  and the stop collar  222  for the shanks of the fasteners  244  thereby providing for ready assembly and replacement of the collar  222 . Triangular passages  248  are formed in the base  232  and the arms  234  for reducing the weight of the housing assembly 
   Referring to  FIG. 17 , the probe assembly  204  comprises an elongated tow bar  250  welded at an outer end to a face plate  252  that is connected to a hitch eyelet  254  by fasteners  256  ( FIG. 11 ). The hitch eyelet  254  terminates with a horizontally projecting arm  258  having an aperture  259  for receiving the shank for the ball  216 . The tow bar  250  includes straight rectangular center section  260  narrower in width than the throat in the guide block  220  having an enlarged circular tail section  262  at the rear end and an enlarged generally triangular head section  264  at the front end. When the tow bar  250  is in the fully retracted position, the tail section  262  engages the base wall of the guide block  220 , nesting at the base wall  238 . When the tow bar  250  is in the fully extended position, the tail section  262  engages the rear guide surfaces  247  of the collars  222 ,  242  to establish a load bearing pivotal connection with the housing assembly  202 . 
   The head section  264  includes rearwardly inwardly inclined sidewalls  272  forming a tapered wedge adapted to nest with the front guide walls  246  in the guide block socket to center the tow probe  204  proximate to and at the retracted position. A through hole  274  is formed in the base  270  for permitting movement of the lock assembly  206  between locked and unlocked positions. between positions, as described below. 
   Referring to  FIGS. 13 through 15 , the lock assembly  206  includes a vertical lock block  280  attached to the top plate and connected to the coupling arm  208  at an upper end. The lock block  280  has a vertical bore aligned with aperture  274  to the arm  260  and corresponding apertures in the plate  224 ,  228 . A cylindrical lock bolt  282  is slidably supported in the bore. The lock bolt  282  includes a reduced diameter shaft  284  at an upper end. A transverse actuating handle  286  is attached the upper end of the shaft  284 . A compression spring  290  is carried on the shaft  284  and compressively retained between the lock bolt and a retaining cap  292  at the upper end of the lock block  280 . Accordingly, the lock bolt  282  is compressively biased to the locked position shown in  FIGS. 13 and 15  wherein the lock bolt passes through the aperture  274  in the tow arm  260 . The handle  286  is raised against the biasing of the spring  290  to an unlocked position whereat the probe assembly  204  may be extended. Thereafter, the lock bolt rides against the top surface of the tow bar until aligned with the tow bar aperture for automatic self biasing to the locked position. 
   In operation, the towing vehicle is backed proximate the hitch of the towed vehicle. The actuating handle  286  is raised to the unlocked position and the tow bar  260  manually extended, and aligned with and coupled in a conventional manner with the towed vehicle hitch box  210 . Thereafter if a considerable misalignment between the vehicles exists, the towing vehicle may be moved forwardly to longitudinally align the tow bar at the pivotal connection between the collars  242 ,  222  and the tail section  262 . Then the vehicle is reversed causing the tow bar tail  262  to engage the rearwardly converging surfaces of the base wall for further alignment and the head to nest in the front housing socket thereby achieving an aligned position whereat the lock assembly is actuated to the locked condition. For lesser misalignments, the towing vehicle may be backed toward the towed vehicle whereby the tail  262  reacts initially with the side walls  240  to begin aligning pivotal movement of the tongue and subsequently reacts with the converging surface of the base wall for final alignment. 
   Having thus described a presently preferred embodiment of the present invention, it will now be appreciated that the objects of the invention have been fully achieved, and it will be understood by those skilled in the art that many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the sprit and scope of the present invention. The disclosures and description herein are intended to be illustrative and are not in any sense limiting of the invention, which is defined solely in accordance with the following claims.