Abstract:
Bodies for hook lift shuttles and other roll-off loaders are fitted with trailer towing hitches, such as fifth wheels and hitch balls, so that when one of these bodies is loaded onto a shuttle or loader, the shuttle or loader can be used temporarily as a tractor for a trailer.

Description:
BACKGROUND OF INVENTION 
     This invention relates to towing of vehicles, in particular towing of trailers, and more specifically to towing of semitrailers. It also relates to truck bodies, more specifically to removable and interchangeable truck bodies, and still more specifically to “hook lift”, cable hoist, and chain hoist “roll-off” loaders, and other specific types of trucks constructed to handle such bodies. 
     Relevant background in the field of trailer towing is as follows: A tractor for pulling semitrailers is commonly equipped rearwardly with a support bearing called a “fifth wheel”, which engages a pin called a “kingpin” on the forward end of the trailer. When so engaged, the tractor-trailer combination comprises an articulating vehicle in which the trailer can rotate about a vertical axis relative to the tractor. 
     Trailers can be towed in similar fashion using other mating bearing combinations such as ball hitches. Ease of hitching and unhitching trailers is an important factor for logistical reasons in the design of tractors, trailers, and hitching mechanisms. 
     Background in the other related field is as follows: In the handling of bulk materials such as solid waste, it is common to use so-called “roll-off” containers to collect and transport the materials. These containers, called “bodies”, come in various shapes and capacities and are adapted to be loaded onto and transported by shuttle trucks specially configured to load and unload them. Some roll-off bodies are more specialized, such as a flat bed for carrying earth-moving machinery. There are various types of shuttle trucks for handling roll-off containers. A hoist roll-off shuttle of the cable or chain variety comprises a chassis with a hydraulic lift bed, a winch, and a cable or chain. The bed comprises rollers to enable roll-off bodies to be winched onto and off of the bed. The hook lift truck also comprises a chassis with a hydraulic lift bed, but instead of a winch, it uses a hydraulically-articulated arm and hook to grasp a hook lift body and pull it onto or lower it from the bed. 
     The present invention relates these two fields in a novel way as summarized below. 
     SUMMARY OF INVENTION 
     The present invention is a removable, e.g., hook lift, body for a shuttle truck, which has been specially constructed to comprise a trailer-towing bearing such as a fifth wheel or a hitch ball. Such construction further comprises means for securely fastening the body to the shuttle so as to maintain the body in rigidly fixed relation to the chassis of the shuttle at all times. The virtue of such a body is that it enables roll-off shuttles to be used temporarily as tractors for semitrailers. This has the potential to reduce or eliminate the need for owning and maintaining dedicated tractors for semitrailers. Conversely, it can expand the capabilities of a fleet of roll-off shuttle vehicles to include trailer towing. 
     It is therefore a primary object of this invention to provide new means for towing trailers. It is a further object of this invention to provide a method of manufacturing or modifying roll-off shuttle beds for the secure installation and placement of such means. It is yet another object of this invention to provide a method of installing such means on such shuttle beds. Other objects of this invention are to expand the uses for roll-off shuttle trucks and to reduce the overall capital and maintenance costs for truck fleets. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a perspective view of a hook lift roll-off shuttle known in the art, without a body in place. 
     FIG. 2 is a perspective view of a portion of the shuttle of FIG. 1 with a prior art dump body in place. 
     FIG. 3 is a perspective view of the first embodiment of the present invention configured to comprise a fifth wheel. 
     FIG. 4 is a side view of the first embodiment. 
     FIG. 5 is a front view of the first embodiment. 
     FIG. 6 is a perspective view of the locking pin mechanism of the present invention in the retracted (unlocked) position. 
     FIG. 7 is a perspective view of the locking pin mechanism of the present invention in the advanced (locked) position. 
     FIG. 8 is a perspective view of a portion of the chassis of the shuttle of FIG. 1 modified to accommodate the first embodiment of the present invention. 
     FIG. 9 is a perspective view of the shuttle of FIG. 1 with hydraulic sections raised and hook attached for installation of the first embodiment of the present invention. 
     FIG. 10 is a perspective view of the shuttle of FIG. 1 with the first embodiment of the present invention secured in place. 
     FIG. 11 is a perspective view of a second embodiment of the present invention. 
     FIG. 12 is a perspective view of a cable hoist roll-off shuttle known in the art, without a body in place. 
     FIG. 13 is a perspective view of a third embodiment of the present invention. 
     FIG. 14 is a perspective view of the third embodiment shown in FIG. 13 about to be installed on the cable hoist roll-off shuttle of FIG.  12 . 
    
    
     DETAILED DESCRIPTION 
     Referring now in greater detail to the drawings, in which like numerals refer to like elements in all of the figures, FIG. 1 is a perspective view of a hook lift shuttle known in the art. The shuttle shown is typical of the hook lift type but there are other shuttles with dissimilar shapes also used to handle interchangeable bodies. The present invention is a body not to be construed to operate only with the shuttle depicted in FIG.  1 . This will become apparent in further discussion. 
     The shuttle of FIG. 1 is shown without any body in place on the bed. It comprises a multi-axle truck with a specialized hydraulically-actuated bed  101  affixed to its chassis. The bed  101  further comprises in relevant part four interconnected sections: a base section  102  fixed to the truck chassis  114 ; a primary or dump section  103  rotatably attached to the base section  102  along axis A; a secondary section  104  also rotatably attached to the base section  102  along axis B; and a tilt section  105  rotatably attached to the secondary section  104  along axis C. 
     The dump section  103 , secondary section  104 , and tilt section  105  may be locked into rigid relationship by remote-controlled dump latches  107 . An operator can then move all three bed sections into dumping position (about axis A) by actuating hydraulic lift cylinder  108 . If dump latches  107  are unlocked, lift cylinder  108  can rotate secondary section  104  and tilt section  105  independently of dump section  103  about axis B. The tilt cylinder  109 , by expanding hydraulically along its own axis, can rotate tilt section  105  about axis C as desired. The operation and function of the various parts are further illustrated in FIG.  9 . 
     Other relevant parts of the prior art shuttle are body latches  110 , which hold the rear of a shuttle body in fixed relation to the rest of the truck while the truck is in motion, rear rollers  111  , which guide a body into position on the bed when it is being loaded, and saddles  112 , which provide further resistance to side-to-side shifting of the load in transit. Also note hook assembly  113 , which is used to grasp, move, and hold lift bodies designed to be handled by such shuttles. 
     FIG. 2 is a perspective view of a portion of the shuttle of FIG. 1 with a prior art dump body  201  in place. Note curved pin  202 , rigidly attached to the upper front of the body  201 , passing through hook assembly  113 . 
     FIG. 3 is a perspective view of the first embodiment of the present invention, a fifth wheel support. It comprises a rigid rectangular frame  301  having one open end  302  at its front. Four legs  303  are attached to the frame near its corners and depend from it. The open end  302  of the frame  301  has attached to either side of it the lower ends of two pin supports  304  which extend upward from the plane of the frame  301  and diagonally towards each other. The upper ends of the pin supports are joined together by a curved pin  202 . Spanning the middle of frame  301  is platform  306 , which supports a fifth wheel trailer hitch  307 . Also spanning the underside of the platform  306  is an optional cross member  308  for further body attachment security. 
     When this fifth wheel support is installed on a shuttle truck, as described further in subsequent figures, pin  202  is encircled by a hook assembly  113  (not shown) and the bottom edges  309  of frame  301  rest upon saddles  112  (not shown) and upon other horizontal members of the truck (not shown). Each leg  303  provides a further means of securement to the truck chassis  114  (not shown) by a tubular locking pin mechanism  310  consisting of a pin  311 , a pin tab  312 , and a tongue  313  at each of the four legs. This means of attachment is more clearly illustrated in FIGS. 6 and 7. 
     FIG. 4 is a side view of the first embodiment. Note that curved pin  202  lies in a plane that is not vertical; i.e., the apex of the pin is forward (to the left of) the pin supports  304  so that it can be held on a truck bed without interfering with the tilt section  105  (not shown) of the truck bed. 
     FIG. 5 is a front view of the first embodiment. Note that in this prototypical example, the pin support  304  consists of two pieces of rigid material welded together for ease of assembly. Also it can be seen in this view that the platform  306  is even with the top of frame  301 , and the cross member  308  is even with the bottom. These locations are a fit with the shuttle depicted in FIG. 1, but many other configurations are possible within the scope of this invention. 
     FIG. 6 is a perspective view of the locking pin mechanism  310  of the present invention in the retracted (unlocked) position. The mechanism  310  is installed at the lower end of each leg  303  of the fifth wheel support. In this illustration, the leg consists of two plates  601  and  602  depending from frame  301 , although the leg could be made from other elongate materials such as, for one example, a single solid piece of rigid material, or for another example, a piece of rigid material having a hollow rectangular cross section. In this illustration, a circular hole  603  is cut horizontally through both plates so that tubular pin  311  can slide smoothly though it. The pin is of a length that when one end of the pin is flush with one side of the leg, the pin projects outward from the other side of the leg by several inches. An elongate tongue  313  is fixedly attached to the bottom of the leg so that it extends outwardly from the frame  301  and at least as far beyond one side of the leg as the pin  311  does. A pin tab  312  is fixedly attached to one end of the pin so that the tab  312  is on the same side of the leg  303  as the tongue  313 . The tongue  313  further comprises a proximal notch  604  and a distal notch  605 , both cut downward from the top edge of the tongue  313 . By use of these notches, the tubular pin  311  can be locked into either of two horizontal positions. If pin tab  312  is lowered into distal notch  605  (as shown), it is held there by gravity and pin  311  will be held in its farthest displacement away from the truck body until the tab is lifted. If the tab  312  is lowered into the proximal notch  604 , the pin  311  will project inwardly from the frame. 
     This is shown in FIG. 7, which is a perspective view of the locking pin mechanism  310  of the present invention in the advanced (locked) position. Note that the tubular pin  311  projects inwardly some distance from the leg  303 . If the truck chassis (not shown) has a collinear round cavity of the same diameter of leg hole  603  (not visible), pin  311  can fit into this cavity and resist motion of the frame  301  in any direction relative to the truck chassis other than coaxial to the tubular pin. 
     FIG. 8 is a perspective view of a the left side of the truck bed  101  of the shuttle of FIG. 1 modified to accommodate the first embodiment of the present invention depicted in FIGS. 3,  4 , and  5 . The modifications shown, which are duplicated in mirror image on the right side of the bed, comprise a forward ear  801 , a forward pin socket  802 , a rearward ear  803 , and a rearward pin socket  804 . The ears are fixedly attached to the truck chassis  114  at an angle towards the truck centerline. As will become clear in the next figure, the invention is installed on top of the truck bed  101  shown here. The two left legs of the invention (not shown) fit alongside (just to the left of) the visible side of the chassis  114 . In like manner, the two right legs of the invention (not shown) fit alongside the right side (not shown) of the chassis. The final positioning of the first embodiment of the invention is shown more clearly in FIG.  10 . 
     FIG. 9 is a perspective view of the shuttle of FIG. 1 with the secondary bed section  104  and tilt section  105  raised and the hook assembly  113  attached to the first embodiment of the present invention. The invention is prepared for installation by making sure the locking pins  311  are in their retracted (fully out) positions, and that the curved pin  202  is grasped by the hook assembly  113 . The invention is installed by using hydraulic cylinders  108  and  109  to lift the forward end  901  of the invention over the rear of the truck chassis so that forward legs  303  are above and forward of rollers  111 . As the invention is pulled hydraulically farther forward, the rearward ears  803  serve to align the lower edges  309  of frame  301  onto the rollers  111 . As the invention is pulled still farther forward, the forward end  901  of the invention must be held above the truck bed until the forward end  901  is near to contacting the rearward vertical face  902  of the tilt section  105  of the shuttle. The forward end  901  of the invention is then lowered into final position. Forward ears  801  serve to. prevent forward legs  303  from hanging up on top of the chassis  114 . At this point, tubular pins  311  will line up with pin sockets  802  and  804 . The pins  311  can then be advanced into the sockets and locked. 
     FIG. 10 is a perspective view of the shuttle of FIG. 1 with the first embodiment of the present invention secured in place. Note that rectangular frame  301  rests in saddle  301  and rollers  111 . Note further that cross member  308  is secured under body latches  110 . Thus the invention is fixedly secured to the truck chassis by four pins  311 , cross member  308 , and curved pin  202 . Fifth wheel  307  is now ready for engagement to the kingpin of a trailer (not shown). 
     FIG. 11 is a perspective view of a second embodiment of the present invention, configured to comprise a hitch ball. In this embodiment, a hitch ball assembly  1101  is substituted for fifth wheel assembly  307  in FIG.  3 . 
     FIG. 12 is a perspective view of a cable hoist roll-off shuttle known in the art, without a body in place. It comprises in pertinent part a dump section  1201  capable of being raised as shown by parallel hydraulic cylinders  1202 . A winch drum (not visible) pulls a cable  1203  over a sheave  1204 . When clevis  1205  is attached to a hook (not shown) on a body made for use on such a shuttle (not shown), the body can be pulled onto the dump section by sliding over rails  1206  and rollers  1207  and may be secured to the shuttle by clamps  1208  and/or other securing devices such as straps (not shown). 
     FIG. 13 is a perspective view of a third embodiment of the present invention, which has the frame of the second embodiment reconfigured to permit installation on the cable roll-off shuttle of FIG.  12 . For clarity it is shown facing the opposite direction as the embodiment shown in FIG.  11 . Note that unlike the first two embodiments, the frame  301  encloses all four sides including forward end  901 . An upward facing hook  1301  replaces the curved pin  202  of FIGS. 3 and 11. Note that the bottom edges of the forward and rearward ends  1302  of the frame  301  are recessed upward from the sides of the frame. This helps this embodiment straddle the rails  1206  of the dump section  1201  as it is being installed (shown in more detail in FIG.  14 ). Any method of alignment and fastening of bodies consistent with safety and the proper operation of the trailer hitch is acceptable. 
     FIG. 14 is a perspective view of the third embodiment shown in FIG. 13 being installed on the cable hoist roll-off shuttle of FIG.  12 . Note that clevis  1205  of the shuttle has been attached to hook  1301 , and cable  1203  has been winched upward to slide the third embodiment onto the dump section  1201  of the shuttle. Note that the right-hand rail  1206  of the dump section has been placed under the forward end  1302  of the frame, and the same is true of the left-hand rail and forward bar although not visible in this view. This centers the invention on the dump section as it is drawn upward by the winch. At a certain point in its upward travel, the frame  301  comes in contact with rollers  1207  on either side of the dump section, reducing the frictional load on the winch. If the dump section has been configured with body latches  110  (only one is visible), cross member  308  will engage them as the body nears the top of its travel, creating security against all motion of the body relative to the truck except rearward. Rearward motion of the body is prevented by the tension of cable  1203 . 
     A fourth embodiment of the present invention combining the fifth wheel hitch assembly of the first embodiment (element  307  of FIG. 3) and the cable roll-off frame adaptations of the third embodiment (FIG. 13) is evident from these illustrations without an illustration of its own and is included within the scope of this invention. 
     While the tubular locking pin mechanism (element  310  in FIG. 3) is claimed matter in this invention as part of the first and second embodiments (FIGS. 3 and 11) of the invention, the invention is not meant to be limited to structures that conform solely to the two prior art shuttles shown in FIGS. 1 and 12, or these shuttles as modified for greater security in FIGS. 8 and 14. The present invention can be configured to fit securely virtually any truck chassis capable of loading assorted bodies. 
     There are also a number of other hitch systems that can be substituted for the two illustrated here (fifth wheel and ball) on the loadable bodies, and they are included within the claimed scope of this invention. Either mating part of any hitch system can be substituted for the fifth wheel or ball of the present invention and suitably affixed to the frame of the loadable body. All such possible hitch combinations cannot be drawn. Examples include, but are not limited to, the pintle hitch, in which a the fifth wheel plate or hitch ball of the present invention could be replaced by a vertical pin or mating eye bolt; and the clevis hitch, in which case it could be replaced by a clevis or a mating hook.