Abstract:
An apparatus and method directed to a stowaway pintle hitch that is simple to manufacture and use having novel height adjustment means, retainer, retainer lock, and stowaway pivoting motion. The apparatus may have a swiveling mount that is free to swivel while towing a trailer. A cushioning spacer is disclosed for reducing impact forces and noise in pintle hitch towing systems. In certain embodiments an apparatus in accordance with the invention may have a trunnion for insertion into a receiver tube or cavity of a vehicle. A base may be secured to the trunnion or to the vehicle. The base may also have a mount secured thereto. The mount may have a platform that is sized and positioned to receive a hitch. The mount may also have a retainer that may be moved into position and locked in order to prevent removal of a pintle ring from around the hitch. The retainer may be mounted on a pivot allowing it to rotate into and out of position. It may also be mounted on a guide such that it may translate relative to the mount. Through rotation and translation, the retainer may be moved to positions suitable for temporarily holding the retainer and for locking the retainer into position. The retainer may be of very simple construction such as a substantially flat plate in which needed apertures and outlines are formed. The mount may be adjustable relative to the base. The apparatus may have another guide to enable the mount to translate relative to the base. This may allow the mount to be height-adjustable and provide versatility of operation. A swiveling mount may allow the mount to swivel relative to the base to accommodate the towing of trailers over rugged terrain. A cushioning spacer made of suitable material may extend around a hitch and absorb impacts and dampen noise.

Description:
RELATED APPLICATIONS  
       [0001]    This patent application claims the benefit of U.S. Provisional Patent Application Serial No. 60/295,123, filed Jun. 1, 2001 and entitled “STOWABLE-LOCK, CONVERTIBLE-PINTLE HITCH AND SILENCER.” This application is also a continuation-in-part of co-pending patent application Ser. No. 09/559,603, filed Apr. 27, 2000, and entitled “STOWAWAY RECEIVER HITCH.” In addition this application is also a continuation-in-part of co-pending patent application Ser. No. 09/699,279, filed Oct. 26, 2000, and entitled “PIVOTING, UNDERSLUNG, STOWAWAY, HITCH MOUNT.” This application is also a continuation in part of co-pending patent application Ser. No. 10/078,322, filed Feb. 12, 2002, and entitled “MONOLITHIC DOUBLE-BALL HITCH.” 
     
    
     
       BACKGROUND  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates to towing apparatus and, more particularly, to novel systems and methods for securing trailers to towing vehicles with hitches.  
           [0004]    2. The Background Art  
           [0005]    Trailers have been towed since the earliest days of the wheel. A cart or wagon towed behind an animal is a trailer. In modem times, trailers are secured to towing vehicles by a multiplicity of methods, including frame-mounted hitches and bumper-mounted hitches. Tractor-trailer rigs often use pintle-type fifth-wheel towing systems. Similarly, recreational vehicles sometimes use fifth-wheel towing systems or often a receiver-type mounted ball hitch.  
           [0006]    A receiver hitch relies on a receiver cavity or tube securely mounted to the frame or undercarriage of a towing vehicle. The receiver may be reinforced and is provided with an aperture for receiving a trunnion. A trunnion may be secured into the receiver by a lock, such as a pin. On the trunnion may be mounted a hitch. The hitch may be a pintle hitch or ball hitch, typically, but need not be limited thereto.  
           [0007]    Pintle style hitches are typically complicated mechanisms and make use of parts having complex geometries. Pintle hitches also generally have complex locking mechanisms that have limited functionality, locking only in one position.  
           [0008]    Typical pintle hitches are bulky and must remain in a deployed position. Accordingly it would be an advancement in the art to provide a pintle hitch system that is stowable while remaining connected to a vehicle. It would also be an advancement in the art to provide a pintle hitch providing this functionality while at the same time having a simple design making it easy to manufacture. Providing a simpler design would also make such a pintle hitch easier and safer to use and less prone to failure.  
           [0009]    Typical hitch systems are designed for towing trailers over substantially smooth roads. There is typically little accommodation for twisting of the trailer relative to the towing vehicle. Thus, it would be an advancement in the art to provide a towing system that was able to accommodate such twisting motion. Such as system would facilitate the towing of trailers and the like over rugged terrain.  
         BRIEF SUMMARY OF THE INVENTION  
         [0010]    An apparatus is disclosed in sufficient detail to enable one of ordinary skill in the art to make and use the invention. In certain embodiments an apparatus in accordance with the invention may have a trunnion for insertion into a receiver tube or cavity of a vehicle. A base may be secured to the trunnion or to the vehicle. The base may also have a mount secured thereto. The mount may have a platform that is sized and positioned to receive a hitch.  
           [0011]    Various details of bases, mounts, and the like are discussed in U.S. patent application Ser. No. 09/559,603 filed Apr. 27, 2000 and entitled STOWAWAY RECEIVER HITCH; U.S. patent application Ser. No. 09/699,279 filed Oct. 26, 2000 and entitled PIVOTING, UNDERSLUNG, STOWAWAY, HITCH MOUNT; and U.S. patent application Ser. No. 10/078,322 filed Feb. 12, 2002 and entitled MONOLITHIC DOUBLE-BALL HITCH incorporated herein by reference.  
           [0012]    The mount may also have a retainer that may be moved into position and locked in order to prevent removal of a pintle ring from around the hitch. The retainer may be mounted on a pivot allowing it to rotate into and out of position. It may also be mounted on a guide such that it may translate relative to the mount. Through rotation and translation, the retainer may be moved to positions suitable for temporarily holding the retainer and for locking the retainer into position. The pivot and guide may be positioned such that the retainer can not be both rotated and translated at the same time. For example, the retainer may be rotated about the pivot and translated into a position where rotation is substantially impossible. This may allow the retainer to be placed out of the way so that a pintle ring can be brought down over the hitch. Likewise the retainer may be brought into a position where it is only possible to rotate the hitch about the pivot. The retainer may be of very simple construction such as a substantially flat plate in which needed apertures and outlines are formed.  
           [0013]    A stop on the platform may engage a surface on a hitch and prevent it from rotating. This may facilitate installation of a hitch. For example, the stop engaging the hitch may enable a user to use a single wrench to tighten down a nut holding the hitch to the platform. The stop could be as simple as a shoulder or flat formed in the platform.  
           [0014]    The mount may be adjustable relative to the base. The apparatus may have another guide to enable the mount to translate relative to the base. This may allow the mount to be height-adjustable and provide versatility of operation. The mount and base may also be secured to one another by a pivot allowing the mount to rotate into a variety of positions. This may enable the mount to be secured in an unobtrusive stowed position.  
           [0015]    Locks may be used to fix the position of the retainer relative to the mount and the position of the mount relative to the base. In some embodiments the locks may be locking pins extending through apertures formed in both of the members to be fixed relative to one another.  
           [0016]    The base may have a height index that receive the locks so that the mount may be secured at a variety of positions relative to the base. In some embodiments the height index may be a series of apertures formed in the base and sized to receive the locking pins.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    The foregoing and other objects and features of the present invention will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only typical embodiments of the invention and are, therefore, not to be considered limiting of its scope, the invention will be described with additional specificity and detail through use of the accompanying drawings in which:  
         [0018]    [0018]FIG. 1 is a perspective view of one embodiment of a pintle-hitch mounting mechanism, in a deployed and closed position, in accordance with the invention;  
         [0019]    [0019]FIG. 2 is a perspective view of one embodiment of a pintle-hitch mounting mechanism, in a deployed and open position, in accordance with the invention;  
         [0020]    [0020]FIG. 3A is a side elevation view of one embodiment of a pintle-hitch mounting mechanism freely rotating about its pivot, in accordance with the invention;  
         [0021]    [0021]FIG. 3B is a side elevation view of a pintle hitch in a deployed and closed position, in accordance with the invention;  
         [0022]    [0022]FIG. 3C is a side elevation view of a pintle hitch-mounting mechanism in a deployed and closed position, in accordance with the invention;  
         [0023]    [0023]FIG. 4 is a perspective view of one embodiment of a retainer suitable for use in accordance with the invention;  
         [0024]    [0024]FIG. 5 is a perspective view of another embodiment of a retainer suitable for use in accordance with the invention;  
         [0025]    [0025]FIG. 6 is an exploded view of a pivot retaining assembly suitable for use in accordance with the invention;  
         [0026]    [0026]FIG. 7 is a perspective view of a pin suitable for use in accordance with the invention;  
         [0027]    [0027]FIG. 8 is a perspective view of another embodiment of a pintle hitch, with the retainer in an open position, in accordance with the invention;  
         [0028]    [0028]FIG. 9 is a perspective view of another embodiment of a pintle hitch, with the retainer in a closed position, in accordance with the invention;  
         [0029]    [0029]FIG. 10 is a perspective view of the apparatus of FIG. 9 having a lockable turntable carrying two hitches, in accordance with the invention;  
         [0030]    [0030]FIG. 11 is a perspective view of a platform suitable for use in the turntable of FIG. 10;  
         [0031]    [0031]FIG. 12 is a perspective view of a turntable assembly suitable for use in the apparatus of FIGS. 10 and 11;  
         [0032]    [0032]FIG. 13 is a perspective view of a multiple hitch assembly suitable for use in the apparatus of FIGS.  10 - 12 ;  
         [0033]    [0033]FIG. 14 is a perspective view of an alternative embodiment of a pivoting mount in accordance with the invention;  
         [0034]    [0034]FIG. 15 is a perspective view of another alternative embodiment of a pivoting mount in accordance with the invention;  
         [0035]    [0035]FIG. 16 is a perspective view of part of an alternative aperture configuration for a turntable assembly;  
         [0036]    [0036]FIG. 17 is a perspective view of an alternative embodiment of the apparatus of FIG. 10;  
         [0037]    [0037]FIG. 18 is a perspective view of an apparatus having a base selectively swivelling with respect to the trunnion, in accordance with the invention;  
         [0038]    [0038]FIG. 19 is an exploded view of the apparatus of FIG. 18;  
         [0039]    [0039]FIG. 20 is an alternative embodiment of the apparatus of FIG. 18;  
         [0040]    [0040]FIG. 21 is an exploded view of the apparatus of FIG. 20;  
         [0041]    [0041]FIG. 22 is a perspective view of an apparatus employing a silencing spacer (e.g. bumper or buffer) in accordance with the invention;  
         [0042]    [0042]FIG. 23 is a perspective view of a silencing spacer suitable for securing to a hitch in accordance with the invention;  
         [0043]    [0043]FIG. 24 is a perspective view of a pintle having a silencing spacer in accordance with the invention;  
         [0044]    [0044]FIG. 25 is a perspective view of a pintle ring having a silencing spacer secured to a pintle ring in accordance with the invention; and  
         [0045]    [0045]FIG. 26 is a perspective view of a silencing spacer suitable for securing to a pintle ring in accordance with the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0046]    It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in FIGS. 1 through 26, is not intended to limit the scope of the invention. The scope of the invention is as broad as claimed herein. The illustrations are merely representative of certain embodiments of the invention. Those presently preferred embodiments of the invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout.  
         [0047]    Those of ordinary skill in the art will, of course, appreciate that various modifications to the details of the Figures may easily be made without departing from the essential characteristics of the invention. Thus, the following description of the Figures is intended only by way of example.  
         [0048]    Referring to FIGS. 1 and 2, an apparatus  10  may include a trunnion  11 . The trunnion  11  may define a longitudinal direction  12   a . Lateral and transverse directions,  12   b  and  12   c  respectively, may be defined so that they are substantially mutually orthogonal to each other and to the longitudinal direction  12   a . Directions  12   a - 12   c  may also be considered to be or define axes  12   a - 12   c . Accordingly, rotational directions  13   a ,  13   b , and  13   c  may be defined as rotation about the axes  12   a ,  12   b , and  12   c , respectively, or axes translated therefrom.  
         [0049]    The trunnion  11  may have any suitable cross-section and length. Additionally, the trunnion  11  may have a lock to maintain it securely fastened to a receiver (not shown), which may be secured to the undercarriage of a vehicle. In one embodiment, the lock may be a locking aperture  14  admitting a locking pin (not shown) therethrough.  
         [0050]    The apparatus  10 , and the components thereof, may have a rearward end  15  and a forward end  16 . This terminology may be used to refer to the apparatus  10  from the reference frame of the towing vehicle. Thus, the rearward end  15  extends away from the towing vehicle and forward end  16  extends toward the towing vehicle. In the certain embodiments of the present invention, the apparatus  10  and the components thereof are made of steel, however, aluminum, other ferrous alloys, or any other material possessing sufficient strength and durability may be used.  
         [0051]    An apparatus  10  may include a base  17 . The base  17  typically attaches to the rearward end  15  of the trunnion  11 . The base  17  is typically substantially permanently attached to the trunnion  11 . In some embodiments, the trunnion  11  may be omitted and the base  17  may secure directly to structures of the towing vehicle. The base  17  may also be embodied as part of the towing vehicle such as a bumper. A base  17  may be embodied as a block  18 . The block  18  may be attached to the trunnion  11  by means of welds, bolts, or other means of attachment An apparatus  10  may include a mount  19 . The mount  19  may secure to the base  17  in a variety of ways. The mount  19  may be secured to the base  17  in a manner allowing for no movement of mount  19  relative to base  17 . The mount may be integrally attached to base  17 . It may be part of the same monolithic piece of material, or it may be attached by means of welds, bolts, or any other suitable securing means.  
         [0052]    The mount  19  may be secured to the base  17  in a manner allowing for movement of the mount  19  relative to a base  17 . In some embodiments of the apparatus  10 , the mount  19  may be pivotably attached to the base  17 . The mount  19  may pivot with respect to the base  17  between a deployed position and a stowed position. In certain embodiments of the apparatus  10 , the mount  19  and base  17  may be configured to allow the mount  19  to translate relative to base  17 . In certain embodiments, the mount  19  may be selectively lockable to the base  17  in a plurality of fixed positions, orientations, or both.  
         [0053]    A mount  19  may include two side beams  22   a ,  22   b  parallel to one another and attached to a platform  24 . Beams  22   a ,  22   b  may attach to platform  24  by any attachment means capable of withstanding the magnitude of forces developed while towing a trailer. In the one embodiment the beams  22   a ,  22   b  are attached to the platform  24  by means of welds. Alternatively, the mount  19  may be formed as a monolithic member comprising surfaces and extensions providing the same functionality as a platform  24  and side beams  22   a ,  22   b.    
         [0054]    In certain embodiments an apparatus  10  may include a hitch  26  such as one that might attach directly to a rearward end  15  of a mount  19 . The hitch  26  may be a ball hitch  26 , a pintle hitch  26  or any other type of hitch  26  suitable for serving as an attachment point for a trailer or other towed vehicle. One embodiment of the present invention may be capable of towing trailers having pintle rings as well as those having ball couplers. Accordingly the hitch  26  would typically be embodied as a ball hitch  26 . In some embodiments the hitch  26  may secure to the platform  24  by means of a threaded bolt  27  and a nut  28 . The platform  24  of the mount  19  may have a stop  29  configured to engage the hitch  26  in a manner to resist rotation of the hitch  26  with respect thereto. A stop  29  may allow a nut  28  to be tightened without requiring user intervention to prevent the rotation of the hitch  26 , thereby reducing the number of tools and hands needed to attach the hitch  26  to the platform  24 . In one embodiment, the stop  29  is a surface  30  formed to correspond to a surface  32  on the hitch  26 . The surfaces  30  and  32  may be flat, or may have any other contour capable of preventing rotation of the hitch  26 .  
         [0055]    A base  17  and a mount  19  may be coupled by means of guides  34 . The guides  34  may provide for translation and rotation of the mount  19  relative to the base  17 . The guides  34  may be integrally or monolithically attached to the base  17  and engage pivots  36  attached to mount  19 . Alternatively the guides  34  may be integrally attached to the mount  19  or be monolithically formed with the mount  19  to engage pivots  36  attached to the base  17 .  
         [0056]    In the embodiment shown, the guides  34  are slots  38  in the block  18 . The slots  38  typically extend in a transverse direction  12   c . A slot  38  may have a width  44  in longitudinal direction  12   a  and a depth  46  in lateral direction  12   b . The pivots  36  may be embodied as studs  40  inserted in the apertures  42  of the side beams  22   a ,  22   b . The studs  32  are typically of sufficient length to extend through apertures  42  and into slots  38  a distance slightly less than the depth  46  of the slot  38 . The studs  40  are typically of suitable dimensions to allow them to rotate and translate substantially freely within the slots  38 .  
         [0057]    An apparatus  10  may also include a lock  48   a  or  48   b  or two locks  48   a ,  48   b . A lock  48   a ,  48   b  may prevent motion of the mount  19  in at least one direction  12   a - 12   c , 13   a - 13   c  relative to the base  17 , when engaged. Two locks  48   a ,  48   b  may be used when towing heavy loads in order to increase the bearing surface transferring loads between the mount  19  and the base  17 .  
         [0058]    A lock  48   a ,  48   b  may be embodied as a pin  50   a ,  50   b  extending through an aperture  52  in the side beam  22   a , through an aperture  54  in the block  18 , and through an aperture  52  in the side beam  22   b . Apertures  54  typically extend through the block  18  in a lateral direction  12   b . Apertures  54  may have substantially similar dimensions and be arranged in a column extending in a transverse direction  12   c . A pin  50   a ,  50   b  through the apertures  52 ,  54  effectively prevents the translation of the mount  19  relative to the base  17 .  
         [0059]    In the embodiment shown a pin  50   a ,  50   b  may also function along with a stud  40  to effectively prevent rotation of the mount  19  relative to the base  17 . The extension of the stud  40  into the slot  38  and the presence of a pin  50   a ,  50   b  passing through the apertures  52 , 54  prevents the rotation of the side beams  22   a ,  22   b  with respect to the block  18  in the direction  13   b  (e.g. about a lateral axis  12   b ).  
         [0060]    Referring to FIGS.  3 A- 3 C, while continuing to refer to FIGS. 1 and 2, a mount  19  may be locked in a variety of positions. With all locks  50   a ,  50   b  disengaged, as shown in FIG. 3A, the mount  19  is free to rotate a lateral axis in direction  13   b  and translate transversely in direction  12   c . A lock  48   a ,  48   b  or multiple locks  48   a ,  48   b  may be used to fix the position and orientation of the mount  19  with respect to the base  17 . A pair of apertures  52  located opposite one another in the side beams  22   a ,  22   b  may be aligned with an aperture  54 , A pin  50   a  may insert therethrough in order to lock the mount  19  in the position shown in FIG. 3B.  
         [0061]    In order to provide greater strength and stability, a second pin  50   b  may insert into a second, opposite, pair of apertures  52  aligned with a second aperture  54 . The possible combinations of opposite pairs of apertures  52  with apertures  54  may correspond to possible heights of the mount  19  relative to the base  17 . For example, in FIG. 3B mount  29  is higher, relative to the base  17 , than the mount  19  shown in FIGS. 1 and 2.  
         [0062]    By rotating the mount  19  about the pivot  36 , the mount may be moved to a stowed position illustrated in FIG. 3C. A pin  50   a ,  50   b  may insert through an aperture  52  in the side beam  22   a , an aperture  54 , and an aperture  52  in the side beam  22   b  in order to lock the mount  19  in the stowed position. One utility of the stowed position is that the mount does not extend away from the vehicle, eliminating the likelihood of obstruction thereby, tripping users or the like. A user is also spared the risk of forgetting that the apparatus  10  is attached to a vehicle and miscalculating the effective length of the vehicle while parking, risking a minor collision.  
         [0063]    Referring to FIGS. 1, 2,  4 ,  5 , and  6 , an apparatus  10  may include a pintle assembly  58 . A pintle assembly  58  typically closes a loop formed by the mount  19  and the hitch  26 , preventing the removal of a pintle ring therefrom. The pintle assembly  58  may include a retainer  60  secured to the mount  19  by means of pivots  62  about which the retainer may rotate about a lateral axis  12   b  in a rotational direction  13   b . The pintle assembly  58  may also include guides  64  along which the retainer  60  may translate relative to the mount  19 .  
         [0064]    In one embodiment the pivots  62  may be embodied as studs  66  inserted into apertures  68  in side beams  22   a ,  22   b . The studs  66  may be retained in the apertures  68  by means of pins, such as a pin  104  (FIG. 8), inserted into apertures  70 . The guides  64  may be embodied as slots  72  (FIG. 4) or a slot  72  (FIG. 5) having a rearward end  73   a , a forward end  73   b , and a width  74 . A slot  72  may have a depth  76  (FIG. 4) or may extend through the entire retainer  60  in a lateral direction  12   b  (FIG. 5).  
         [0065]    The studs  66  may extend through the side beams  22   a ,  22   b  and into the slots  72  or single slot  72 . In embodiments of the pintle assembly  58  having the retainer  60  of FIG. 4, studs  66  typically extend into the slots  72  a distance no greater than the depth  76 . In embodiments of the pintle assembly  58  having the retainer  60  of FIG. 5, the studs  66  may extend partially through the slot  72  or may be embodied as a single stud  66  extending through one aperture  68  in a side beam  22   a , through the slot  72 , and through a second aperture  68  in a side beam  22   b . A stud  66  is typically of suitable dimensions to allow it to rotate and translate substantially freely within a slot  72 .  
         [0066]    A pintle assembly  58  may also include a lock  78 , which may enable a user to fix the position of the retainer  60  with respect to the mount  19 . The lock  78  may be embodied as a pin  80 . The retainer  60  may be oriented in the position shown in FIG. 1 with the rearward end  73   a  of the slot  72  or slots  72  aligned with the aperture  82  and the forward end  73   b  aligned with the aperture  68 . A pin  80  may then be inserted through the aperture  82  in side the beam  22   a , through the retainer  60 , and through the aperture  82  in the side beam  22   b  in order to lock the retainer  60  in a closed position suitable for retaining a pintle ring as shown in FIG. 1.  
         [0067]    For the retainer  60  shown in FIG. 4 the pin  80  passes through the aperture  84  when the retainer  60  is locked in a closed position. For the retainer  60  shown in FIG. 5 the pin  80  extends through the rearward end  73   a  of the slot  72  in the closed position.  
         [0068]    The rearward end  73   a  of the slot  72  or slots  72  may be aligned with an aperture  68 , such that for the retainer  60  of FIG. 4, the studs  66  extend into slots  72 , or, for the retainer of FIG. 5, the stud  66  or studs  66  extend into the rearward end  73   a  of the slot  72 . The forward end  73   b  of the slot  72  or slots  72  may be aligned with the aperture  86  and a pin  80  inserted therethrough in order to lock the retainer  60  in the open position shown in FIG. 2.  
         [0069]    For the retainer  60  shown in FIG. 4, the pin  80  passes through the aperture  88  when the retainer  60  is locked in an open position. For the retainer  60  shown in FIG. 5, the pin  80  extends through the forward end  73   b  of the slot  72 .  
         [0070]    With the stud  66  or studs  66  aligned with the rearward end  73   a  and the retainer oriented in an open position as in FIG. 2, gravity may maintain it in this position and the base  17  may prevent the rotation of the retainer  60  until the retainer  60  is translated upward  12   c.    
         [0071]    Accordingly, when a user is securing a trailer to the hitch  26 , he or she does not need to insert a locking pin  80  into aperture  86  in order to maintain the retainer  60  out of the way. Interference by the base  17  may likewise prevent translation of the retainer  60  until it has been rotated substantially to the open position of FIG. 2.  
         [0072]    A stud  40 ,  66  may be embodied as shown in FIG. 6, having a shaft  92  of length  94 . A stud  40  or stud  66  used with the retainer  60  of FIG. 4 typically has a length  94  such that the shaft  92  extends through the side beams  22   a ,  22   b  and into the slots  38 ,  72 , but not into the apertures  54 ,  84 ,  88 . A shaft  92  may have a width  94  or diameter  94  sized somewhat smaller than the width  44 ,  74  of a slot  38 ,  72  sufficient to allow a shaft  92  to slide and rotate within a slot  38 ,  72 . A stud  40 ,  66  may secure substantially permanently to the mount  19 . One benefit of such a configuration being that the apparatus  10  is easily adjustable, yet the movable parts are theft resistant.  
         [0073]    A stud  40 ,  66  may have a groove  102  such that when the stud  40 ,  66  is inserted into an aperture  42 ,  68 , a press pin  104  may be inserted into the aperture  70  and engage the groove  102 , preventing the removal of the stud  40 ,  66 . A press pin  104  may have a shaft  106  having a diameter  108  slightly larger than the diameter  110  of the aperture  70  or have splines or the like to effect securement. The press pin  104  may have a groove  112  along its length facilitating constriction of the shaft allowing the press pin  104  to be pressed into the aperture  70 .  
         [0074]    A pin  48   a ,  48   b ,  80  may be embodied as the pin shown in FIG. 7. The shaft  116  of the pin  48   a ,  48   b ,  80  is typically of sufficient length  118  to extend through both cross beams  22   a ,  22   b . The shaft  116  typically has a diameter  120  such that the shaft  116  may be manually inserted through apertures  52 ,  54 ,  82 ,  86 . The head  122  typically has a diameter  124  that cannot be inserted through the apertures  52 ,  54 ,  82 ,  86 . A pin  48   a ,  48   b ,  80  may have an aperture  126  sized to receive a fastener  128 , such as a cotter pin  128  or any other suitable fastener. A pin  48   a ,  48   b ,  80  may have a handle  130  inserted into an aperture  132 , providing for a user to easily grasp the pin  48   a ,  48   b ,  80  for removal from the apparatus  10 .  
         [0075]    A pintle assembly  58  may be embodied as shown in FIGS. 8 and 9. The slot  72  may be embodied as an aperture  72  extending through the retainer  60 . The retainer  60  may be restricted from translating relative to the pivot  62  in the configuration of FIGS. 8 and 9. The retainer  60  may also be shaped as a hook. The apertures  88  and  84  may be positioned at other locations on the retainer  60 , as shown, rather than in a slot  72 .  
         [0076]    The aperture  88  may be aligned with the aperture  82  and a pin  80  inserted therethrough in order to lock the retainer in an open position as shown in FIG. 8. The open position shown may enable a user attaching a trailer having a ball type trailer attachment to the apparatus  10  to have an extra degree of safety. The retainer  60  will not interfere with the normal operation of the trailer attachment, however, it may prevent the complete detachment of the trailer attachment in the event of failure or improper attachment to the hitch  26 . The open position may also permit a user to use a larger sized hitch  26 . For a larger sized hitch  26  the open position of FIG. 8 could be considered a closed position with large clearance. The aperture  84  may be aligned with the apertures  86  in the side beams  22   a ,  22   b  and a pin inserted therethrough in order to lock the retainer  60  in a closed position shown in FIG. 9.  
         [0077]    Referring to FIGS.  10 - 13 , the apparatus  10  may comprise a turntable assembly  200  having one or more hitches mounted on a turntable  204  having one or more surfaces  202   a ,  202   b  . The surfaces  202   a ,  202   b  may have an aperture  204  therethrough sized to receive a stud  27  or bolt  27  used for mounting a hitch  26 . The turntable  200  may be mounted in the platform  24  in a manner allowing the turntable to rotate relative to the platform  24 . The turntable  200  may connect to or be fabricated to have a shaft  206  inserted into an aperture  208  of the platform  24 . The shaft  206  and aperture  208  are typically sized such that the shaft  206  may rotate within the aperture  208 .  
         [0078]    The shaft  206  may receive a retainer  210  securing the shaft  206  against removal from the aperture  208 . Some embodiments of the an apparatus  10  in accordance with the invention may have multiple hitches  26   a,b  which may rest on surfaces  202   a ,  202   b . The turntable  200  may, accordingly, rotate in a direction  13   a  in order to orient a particular hitch  26   a ,  26   b  properly for towing. For example, in FIG. 10, the hitch  26   a  is oriented suitably for attaching to a conventional trailer tongue attachment mechanism. The turntable  200  could be rotated  180  degrees in order to orient hitch  26   b  suitably for attaching to a conventional trailer tongue attachment mechanism.  
         [0079]    The apparatus  10  may include a lock  212 , which enables a user to prevent rotation of the turntable  200 . The lock  212  may comprise a pin  214 , which may insert into an aperture  216  in the side beam  22   a , aperture  218  in the platform  24 , aperture  220  in the shaft  206 , and an aperture  216  in the side beam  22   b  in order to lock the turntable  200  in deployed positions (i.e. either hitch  26   a  or  26   b  oriented suitably for attachment to a conventional trailer attachment). The pin  214  may insert through an aperture  222  in the side beam  22   a , aperture  224  in the platform  24 , aperture  226  in shaft  206 , and an aperture  222  in the side beam  22   b  in order to lock the turntable  200  in a stowed position. The hitches  26  may be a quarter revolution in direction  13   a  from the position shown in FIG. 10. The stowed position allows the mount  19  to be oriented as shown in FIG. 3C without a hitch  26   a ,  26   b  interfering with the trunnion  11 .  
         [0080]    Referring to FIG. 13, a hitch  26   a ,  26   b  may include flats  32  configured to receive a wrench for controlling rotation of the hitch  26   a ,  26   b  during securement to a supporting surface. Also, a flat  250  on the hitch  26   a ,  26   b  may provide space for a label identifying the load rating and other significant information about the hitch  26   a ,  26   b . A hitch  26   a ,  26   b  may also include a ball  252  supported by a neck  254  having a flange  256  or base  256 .  
         [0081]    A stud  27  may typically be integrally formed with the ball  252 , neck  254 , and flange  256  or base  256 . The stud  27  may secure the hitch  26  to a suitable platform  24  or surface  202   a ,  202   b  for towing. In certain embodiments, the stud  27  and neck  254  may be of approximately the same size in order to provide equal strength and to reduce stress concentrations that otherwise occur with substantial changes in cross section.  
         [0082]    A hitch  26   b  may have a pedestal  258  having a height  260  significantly larger than that of the base  256  of hitch  26   a . The base  256  acts primarily to register the hitch  26  and stud  27  with respect to a supporting mount  19 , while also supporting a loading couple occasioned by radial loads on the hitch  26   a ,  26   b  The hitch  26   b  is supported by a shoulder  262  adapted to fit against a mounting surface of a suitable mount (e.g. platform  24 , or surfaces  202   a ,  202   b ) for holding the first hitch  26   a  and hitch  26   b  bolted together by the stud  27 . The shoulder  262  supports axial and bending loading on the hitch  26   b.    
         [0083]    Wrench flats  32  on the pedestal  258  are sized and shaped to receive a wrench for preventing rotation of the hitch  26  in a circumferential direction during installation or removal from a platform  24 , or surface  202 . Also, a flat  250  for a label may be imprinted with a load rating or other significant information associated with the ball hitch  152 .  
         [0084]    Unlike the flange  256 , or base  256 , of the hitch  26   b , the pedestal  258  need not have a stud  27  formed to receive a nut  28  for securement to a mount  19 . Instead, the pedestal  258  may be formed to have a length  260  for receiving a substantial portion of the stud  27 . Accordingly, a threaded aperture  264  may receive a threaded stud  27 . A lock washer may be interposed between shoulder  262  and the surface  202   b  to prevent loosening of the hitches  26   a ,  26   b  due to vibration.  
         [0085]    The pedestal  258  is formed to have a cross-sectional area effective to support the stresses imposed by engagement of the threads of the threaded aperture  264  and stud  27 . The cross-sectional area of the pedestal  258  is sufficient to distribute stresses between the stud  27  and the neck  254  of hitch  26   b , without radical changes in axial cross-sectional area. For example, the neck  254  cannot simply be bored to have an aperture  264  and still maintain all of its structural integrity. Such an undermining of the neck  254  severely restricts the load rating for which the hitch  26   b  could be rated.  
         [0086]    Instead, the continuity of material and stress distributions extends from the neck  254  of hitch  26   a  through the stud  27  to the pedestal  258  and neck  254  of hitch  26   b . Thus, the hitch  26   a  and hitch  26   b  may be supported at their fully rated load, as if each were a single ball hitch having its own original rating in accordance with its size and conventional standard.  
         [0087]    Referring to FIG. 14, while continuing to refer generally to FIGS.  1 - 12 , the apparatus  10  may include a base  17  that is not rectangular. For example, the pivot  36  securing the mount  19  to the base  17  and trunnion  11 , may itself be cylindrical. The mount  19  may have a lock  48  that uses or relies upon a single aperture  52 .  
         [0088]    The hitch  26  may still be selectively positioned between a stowed position and a deployed position by rotating a mount  19  about the pivot  36 . The pivot  36 , however, may rely on a pin  40  having more functions in certain alternative embodiments. For example, the pin  40  may support the loads in all directions  12   a - 12   c    
         [0089]    The concept of a cotter pin  128  or keeper  128  may still be relied upon. Likewise, a head  300  on the pivot  36  (the pivot pin  40  being a specific embodiment thereof) may support a load in a transverse direction  12   c , rather than providing retainage in a lateral direction  12   b . Nevertheless, as a practical matter, a pin  50   a,b  may support loads in the transverse direction  12   c  depending upon the design of clearances between the head  300  and the cylinder  302  of the base  17 . Likewise the clearance between the pin  50  and the aperture  52  through the cylinder  302 , and the pin  40  may be significant.  
         [0090]    For convenience, any of the pins  50 ,  66 ,  80  may include a handle  308  for manipulation. When tolerances or clearances are tight, some rotation of a pin  50 , 80  may be beneficial in order to more easily remove or insert the pin  50 , 80 . An additional point concerning the head  300 , of the pin  40  is the that the head  300  may be either removable or integral. Since the locking pin  50  actually secures the position of the pivot  36 , no great risk is presented by the head  300  being threaded or otherwise secured to the pin  40 , rather than being secured monolithically. Thus, the pin  40  may be replaceable by one of different length (e.g. height) to provide a desired offset  306  in various embodiments of the apparatus  10  manufactured or sold.  
         [0091]    Referring to FIGS. 15 and 16, while referring generally to FIGS.  10 - 13 , An apparatus  10  may have a base  17  shaped as a cylinder  302 , as described in FIG. 13. In addition the pin  40  may be prevented from moving in the downward vertical direction  12   c  by a snap ring  301 . The apparatus  10  may also include a turntable assembly  200  as described in FIGS.  10 - 13 . In some embodiments the platform  24  may be shaped as a cylinder  24  attached to pin  40  by means of a weld  322  or some other suitable means of attachment. The turntable  204  may comprise two legs  201   a  and  201   b  oriented at an angle  324  relative to one another with one leg  201   b  secured to the shaft  206 . The apertures  220  and  226  (FIG. 16) may be positioned such that their axes  326  and  328  are co-planer and oriented at an angle  330  from each other. The angle  330  is typically about 90 degrees. For a turntable assembly  201  having the configuration of FIG. 16, cylinder  24  may operate with a single aperture  218  extending therethrough rather than two apertures  218 ,  224 .  
         [0092]    Referring to FIG. 17, an apparatus  10  may have a mount  19  having side beams  22   a ,  22   b  having an alternative configuration. For example, beams  22   a ,  22   b  may have an “L” shape with one arm  332   a  secured to the base  17 , and another arm  332   b  secured to the pintle assembly  58  and platform  24 . Such a configuration may provide a more light weight mount requiring less material.  
         [0093]    Referring to FIGS. 18 and 19, a mount  19  may be secured to a trunnion  11  by a pivot  400 , allowing the mount to rotate in a rotational direction  13   a  while towing a vehicle. This may be useful when towing vehicles on rocky terrain. In such circumstances the difference in orientations of the vehicle and trailer can exceed the rotational limits or constraints of an ordinary hitch system. Allowing the mount  19  to freely rotate accommodates the rotation of the trailer about a longitudinal axis  12   a  relative to the vehicle without interference.  
         [0094]    The pivot  400  may be embodied as a shaft  402  attached to the trunnion  11  or formed as an integral, or even homogeneous, part thereof. The shaft  402  may pass through an aperture  404  in the base  17 . A retainer  406  may prevent removal of the base  17  from the pivot  400 . The retainer  406  may be embodied as a plate  408  having apertures  410 . Fasteners  412  may be inserted through the apertures  410  and into the apertures  414  in the shaft  400 . Apertures  414  may be threaded such that the fasteners  412  may be embodied as bolts, which may be screwed into the apertures  414 . The apparatus  10  may have a bushing  416  to help facilitate rotation and resist abrasion of the bearing surfaces. The shaft  402  may also have a restraint  418 , such as a key  418 , pin  418 , stud  418 , or shoulder  418 , or other limiter  418  to restrain movement of the mount  19  in the longitudinal direction  12   a.    
         [0095]    Referring to FIGS. 20 and 21, an alternative embodiment of the apparatus of FIGS. 18 and 19 may have a lock  420  allowing a user to restrict the rotation of the mount  19  about a longitudinal axis  12   a  relative to the trunnion  11 . The lock  420  may be embodied as a pin  422  inserted through the aperture  424  in the base  17  and engaging a groove  426  formed in the shaft  402 . A retainer  428  such as a snap ring  428 , stud  428 , key  428 , pin  428 , or shoulder  428  may also be formed in the shaft  402  to retain the bushing  416 , preventing it from sliding over the groove  426 .  
         [0096]    Referring to FIG. 22, A pintle ring  26  attached to an extension  438  may be used to secure a trailer tongue to a hitch  26 . Relative movement between the hitch  26  and the pintle ring  436  can cause several problems. For example, a towing vehicle may accelerate a certain amount before the hitch  26  transfers motion to the towing load. When the slack is taken up and the transfer of force is made, it may be made through an impact event. Even for small distances and accelerations, impact loadings between a hitch  26  and a pintle ring  436  may be large enough to break components of an apparatus  10 . Localized stresses can deform and abraid components. Additionally, this movement and impact may be noisy, cause excessive wear, and cause control problems.  
         [0097]    A spacer  440  or silencer  440  may be fitted to the hitch  26  or a pintle ring  436  to fill the space between the hitch  26  and the pintle ring  436 . The spacer  440  may transfer force between a hitch  26  and a pintle ring  436  before the relative velocity between the vehicle and trailer becomes excessive. By filling the space between the hitch  26  and the pintle ring  436 , a spacer  440  ensures that force will be transferred between the hitch  26  and the pintle ring  436  as they begin to accelerate relative to one another. The spacer  440  may provide shock absorption to reduce the impulse or force of impacts. The spacer  440  may be constructed of a material that is wear resistant.  
         [0098]    Referring to FIG. 23, a spacer  440  may have an aperture  444  having a diameter  446  sized to enable the retainer  440  to fit around a hitch  26 . In such an embodiment, the spacer  440  may be formed of a resilient (e.g. elastomeric)material having the ability to stretch, deform, and return allowing it to be slipped on manually and then fit snugly, and evenly grip. In an alternative embodiment, the spacer  440  may be formed directly onto a hitch  26 . For example, the spacer  440  may be injection molded directly onto the hitch  26 . This may be helpful with stiff or less resilient material.  
         [0099]    The spacer  440  may have an outside diameter  448  sized to allow a pintle ring  436  to be placed around the spacer  440 . The spacer may have a lip  450  sufficiently compliant to allow the pintle ring  436  to pass over yet providing a retaining force resisting the removal of the pintle ring  436 . The spacer  440  may have a base  452  extending below a pintle ring  436  providing a cushion between the pintle ring  436  and the platform  24 .  
         [0100]    Referring to FIGS. 22 and 24, a hitch  26  may instead be embodied as a ball hitch  26  or as a conventional pintle hitch  26 . Either type of hitch  26  be used as a pintle and thus may make use of a spacer  440 . In that role a pintle hitch  26 , in accordance with the present invention, may have any suitable geometry. The pintle hitch  26  may be formed to have a crown  456  for making contact with a retainer  60 . The crown  456  may be supported by a neck  458 . The neck  458  may have a diameter selected to provide sufficient strength to accommodate desired towing loads. In addition, the neck  458  may be shaped to engage or retain a spacer  440 . For example, the neck  458  may be narrower than the crown  456  such that force is required to deform a spacer  440  having a diameter  446  substantially the same as that of the neck  458  in order to pass it over the crown  456 . Alternatively, the spacer  440  may be formed around the neck  458 .  
         [0101]    Referring to FIGS. 25 and 26, a spacer  440  may be formed to remain attached to a pintle ring  436  during normal operation. Accordingly a lip  450  and base  452  may extend far enough such that the spacer  440  will remain attached to the pintle ring  436  when it is passed over a hitch  26 . The diameter  446  may also be made sufficiently large such that passing the pintle ring  436  over a hitch  26  does not cause detachment of the spacer  440  from the pintle ring  436 . In one embodiment, the spacer  440  may be formed onto the pintle ring  436 .  
         [0102]    The various embodiments of mounts  19 , bases  17 , pintle assemblies  58 , spacers, and the like provide for a large number of different combinations. The applications incorporated herein by reference present additional possible embodiments of mounts, bases, and the like. Combinations of the above mentioned embodiments, yielding an apparatus  10  in accordance with the invention, are therefore also within the scope of the present invention. Combinations of the various embodiments of the components of the above described invention are therefore hereby disclosed in sufficient detail as examples to allow one skilled in the art to make and use the same without undue experimentation.  
         [0103]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.