Abstract:
A bow end is provided for a retractable cover assembly for a container, the container having an open top and a side rail extending along each side of the container, and the cover assembly having a tarpaulin sized to cover the open top in an extended position, the cover assembly including a plurality of arcuate bows attached to the cover assembly and configured to support the tarpaulin and to span the width of the container. The bow end is engaged to the each end of each arcuate bow and comprises a one-piece body defining a bow receiving portion with a bore configured to receive an end of the arcuate bow therein, the bow receiving portion including a surface arranged for sliding contact with a top rail when the bow end is engaged to an arcuate bow of the cover assembly. The one-piece body further includes an outboard portion integral with the bow receiving portion and extending substantially vertically downward from the bow receiving portion when the bow end is engaged to an arcuate bow of the cover assembly, the outboard portion extending vertically below the top rail of the container and defining an opening for receiving a drive cable of the cover assembly.

Description:
REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a non-provisional filing of and claims priority to co-pending provisional application No. 61/832,916, filed on Jun. 9, 2013, the entire disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    The present disclosure relates to slidable cover systems for covering a container, truck body or container, and more particularly to a bow end for such systems. 
         [0003]    Slidable cover systems are used to cover the open top of a container body and then slide to one end of the body to permit access to the load within the container body. Thus, a container body C may be in the form of a trailer for carrying a load L, as shown in  FIG. 1 , a dump truck body or a non-mobile container. The container body includes a cover or tarpaulin T supported by bows B, in which the bows are curved to provide clearance for the load L, particularly a heaped load. The bows B include a bow end structure E at the opposite ends of the bows that are configured to slide along opposite side rails SR of the container C. The bow end structure, or bow ends, E are configured to engage a drive system D, which includes a drive cable DC, as best shown in  FIG. 2 . 
         [0004]    One example of a prior bow and bow end is shown in  FIG. 3 . The bow assembly  10  includes a curved bow  11  having straight ends  13  that are configured to ride along the top rail TR of the container C. The ends  13  terminate in a cable gripping element  14  that is configured to be slidably engaged around a drive cable DC. The cable gripping element is typically in the form of clamp halves, with one half integral with the bow end  13  and the other half removable fastened to the bow end half, such as by a bolt. Some bow assemblies include a low friction element  15  disposed around the bow end  13  to facilitate sliding along the top rail. 
         [0005]    The prior bow systems, such as the systems shown in  FIGS. 1-3 , suffer from poor water drainage of the tarp T due to the flat or linear section  13 . Moreover, in such prior systems the tarp tends to wear out as it becomes trapped underneath the bow and bow end as it slides. The prior bow systems are also difficult to integrate with a tarp hold-down system that prevents the tarp from billowing upward as the container is transported on the road. Finally, since the bow end  13  is integral with the bow  11  itself, replacing the bow end requires replacing the entire bow, or replacing the bow requires replacing the bow end. Furthermore, the process of replacing either bow or bow end is very cumbersome with these prior bow systems. 
       SUMMARY 
       [0006]    In accordance with one aspect, a bow end is provided for a retractable cover assembly for a container, the container having an open top and a side rail extending along each side of the container, and the cover assembly having a tarpaulin sized to cover the open top in an extended position, the cover assembly including a plurality of arcuate bows attached to the cover assembly and configured to support the tarpaulin and to span the width of the container. The bow end is engaged to the each end of each arcuate bow and comprises a one-piece body defining a bow receiving portion with a bore configured to receive an end of the arcuate bow therein, the bow receiving portion including a surface arranged for sliding contact with a top rail when the bow end is engaged to an arcuate bow of the cover assembly. The one-piece body further includes an outboard portion integral with the bow receiving portion and extending substantially vertically downward from the bow receiving portion when the bow end is engaged to an arcuate bow of the cover assembly, the outboard portion extending vertically below the top rail of the container. The outboard portion defines a drive cable opening for receiving a drive cable of the cover assembly. 
         [0007]    The one-piece body includes a stabilizing opening that is configured to receive a tensioning strap or a portion of the drive cable. In one embodiment the stabilizing opening is defined in the bow receiving portion and is configured to receive a tensioning strap that extends across the top rail of the container. In another embodiment the stabilizing opening is defined in the outboard portion vertically below the drive cable opening and configured to loosely receive the lower portion of the drive cable. 
     
    
     
       DESCRIPTION OF THE FIGURES 
         [0008]      FIG. 1  is a perspective view of a container with a sliding cover system of the prior art. 
           [0009]      FIG. 2  is a detailed perspective view of a bow end of a prior art sliding cover system. 
           [0010]      FIG. 3  is a side view of a bow assembly of a prior art sliding cover system. 
           [0011]      FIG. 4  is a side view of a bow assembly incorporating a bow end according to one aspect of the present disclosure. 
           [0012]      FIG. 5  is a side view of the bow end of the bow assembly shown in  FIG. 4 . 
           [0013]      FIG. 6  is an enlarged perspective view of a bow assembly with the bow end use of  FIG. 4  depicted in its operative position on the top rail of a container and engaged to the drive cable of the container. 
           [0014]      FIG. 7  is an enlarged view of the bow end of  FIG. 5  in its operative position with a tarpaulin or flexible cover fastened thereto. 
           [0015]      FIG. 8  is an enlarged view of a bow end and bow assembly as shown in  FIG. 4  depicted with the bow end pivoted or rotated slightly from its operative position. 
           [0016]      FIG. 9  is a cut-away view of the bow end of  FIG. 8 . 
           [0017]      FIG. 10  is a perspective view of a bow end according to a further aspect of the present disclosure. 
           [0018]      FIG. 11  is an exploded perspective view of the bow end shown in  FIG. 106 . 
           [0019]      FIG. 12  is an exploded side view of the bow end shown in  FIG. 10 . 
           [0020]      FIG. 13  is an enlarged end view of a portion of the bow end shown in  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the invention is thereby intended. It is further understood that the present invention includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the invention as would normally occur to one skilled in the art to which this invention pertains. 
         [0022]    In order to address the deficiencies of the prior bow and bow end systems, a bow assembly  50  is provided with a curved bow  51  terminating at each end in a novel bow end element  52 , as shown in  FIGS. 4-6 . The bow  51  may be configured as a typical bow, meaning that it exhibits a curvature to accommodate the load within the container. However, unlike the bows of the prior bow systems, the bow  51  terminates in a blunt end  51   a , rather than in the flat or linear end of prior systems (as shown in  FIG. 2 ). As best seen in  FIG. 5 , the bow end  52  includes a one-piece molded body  54 , preferably formed of a high strength plastic material capable of withstanding the load and corrosive environment typically experienced by the container and cover system. The molded body  54  defines a bow receiving portion  55  that includes a bore  58  for receiving the end  51   a  of the bow  51 . The bore  58  extends slightly beyond bolt holes  56   a ,  56   b  defined in the bow receiving portion  55 . It is contemplated that the bore  58  is complementary with the shape of the bow end  51   a . The bolt holes  56  receive a standard fastener F ( FIG. 6 ), such as a bolt, that pass through an opening in the bow end  51   a  aligned with one of the bolt holes  56   a ,  56   b . The bolt holes  56   a ,  56   b  thus provide a quick and easy way to fasten the bow end  52  to a bow, which of course greatly facilitates replacement of the bow and either or both of the bow ends. In one aspect, two bolt holes  56   a ,  56   b  are provided to accommodate an adjustable bow width by selecting which bolt hole is aligned with the corresponding bolt hole in the bow end  51   a . In other words, for a shorter bow width, the bow end  51   a  can be pushed into the bore  58  for engagement with the innermost bore  56   b . On the other hand, for a longer bow width the bow end can be aligned with the outermost bore  56   a . It is further contemplated that for certain cover assemblies it may be desirable to fasten one end of the bow at the opening  56   a  for one bow end and to fasten the opposite end of the bow to the opening  56   b  of the opposite bow end. 
         [0023]    The bow receiving portion  55  includes a surface  59  adapted for sliding contact with the upper surface of the top rail TR of the container body, as shown in  FIG. 6 . The surface  59  is configured for low-friction contact with the top rail, which may be metal or may itself include a low-friction coating. The surface  59  may be generally flat or may convexly curved to provide a line contact with the top rail. In certain embodiments the surface  59  is preferably flat with a width sufficient to provide stability to the bow end  52 , such as to prevent fore-aft wobbling of the bow assembly  50  as the cover system is extended or retracted. The surface  59  may be made of the same material as the one-piece body  54 , may incorporate a friction-reducing composition, such as embedded graphite particles, or may include a low-friction plate fastened to the body. 
         [0024]    The body  54  of the bow end  52  further includes an outboard portion  60  that is generally perpendicular to the surface  59 . The body  54  of the bow end  52  is configured so that the bow receiving portion can engages the bow while the outboard portion  60  is disposed immediately outboard of the top rail TR of the container, as shown in  FIG. 6 . The perpendicular alignment of the outboard portion  60  centers the bow assembly, and thus the cover system, between the side rails of the container—i.e., the outboard portions serve as an “anti-shift” device to keep the cover system from shifting laterally relative to the container. The outboard portion  60  defines an inwardly facing surface  63  that is adapted for sliding contact with the side surface of the top rail TR. The inward surface  63  may thus be configured similar to the surface  59  on the rod receiving portion in that it is configured for low-friction sliding contact with the top rail. The surface  63  may be flat or curved for the same reasons discussed above. 
         [0025]    As seen in  FIG. 5 , the top of the bow-receiving portion  54  is angled relative to the surface  59  and transitions smoothly to the perpendicular outboard portion  60 . In particular, the bow receiving portion  54  is at a non-perpendicular obtuse angle relative to the outboard portion. Thus, the bow end  52  does not include any horizontal portion that might collect water, as with prior bow assemblies. In order to reduce material while maintaining adequate strength, the one-piece body of the bow end  52  may constitute a rib and web construction. Thus, as shown in  FIG. 5 , the body may include vertical and horizontal ribs  70  with thin webs  72  between the ribs. The rib and web construction can be readily incorporated into a molded bow end. 
         [0026]    In one aspect, the bow end  52  includes a feature for fastening the bow end to the tarpaulin T. In particular, the outboard portion  60  defines a bore  75  configured to receive a fastener, such as a screw S that passes through the tarp T, as shown in  FIG. 7 . Each bow end is fastened to the tarp in a similar manner. In one embodiment, the bore  75  is above the drive cable or the drive cable upper portion DC U  but close to the vertical plane of the drive cable. Alternatively, a bore  76 , shown in phantom in  FIG. 6 , may be used to fasten the tarp to the bow end directly in the vertical plane of the drive cable. This configuration can reduce tipping or rotation of the bow end (as illustrated in  FIG. 8 ). As a further alternative, a bore  77 , shown in phantom in  FIG. 6  may be defined in the bow end offset below the drive cable DC U  by the same distance that the bore  75  is offset above the cable. The tarp T would thus be fastened with two screws S, one in the bore  75  and the other in the bore  77  to thereby provide balanced counter forces between the tarp T and bow end, and thus reduce tipping or rotation of the bow end. 
         [0027]    The outboard portion  60  defines a bore  62  for receiving a drive cable. In one embodiment, the bow end  52  of the endmost bow in the cover assembly is provided with a device for fixing the bow end to the drive cable DC so that movement of the cable will cause movement of the bow end and consequently the rear bow. The device may be in the form of a friction collet or in a collar and locking nut configuration, as is known in the art. In the embodiment illustrated in  FIG. 5 , it can be seen that the drive cable must be threaded through the bore  62 . Movement of the rear bow causes movement of the intermediate bows either as the tarp is extended to pull the successive bows, or as the rear bow is retracted to push the successive bows by contact. 
         [0028]    In the embodiment of  FIG. 5 , the drive cable DC must be threaded through the bores  62  of all the bow assemblies used in the cover system, as depicted in  FIG. 6 . In an alternative embodiment shown in  FIGS. 10-13  a bow end assembly  100  includes a cable retention mechanism  102  that allows the drive cable DC to be introduced into a bow end that has already been installed on a bow. The bow end assembly includes a one-piece body  104  similar to the body  54  in that it includes a bow receiving portion  106  and an outboard portion  108  that define the corresponding surfaces for sliding contact with the top rail of the container body. However, in one modification, rather than the bore  62 , the outboard portion  108  defines a side-opening channel  110  that permits introduction of the drive cable from the side of the bow end assembly  100 . The channel  110  defines an interior portion  112  (best seen in  FIG. 12 ) that is configured to conform to the drive cable—i.e., the interior portion is circular to match the circular cable. The interior portion  112  opens to a retention opening  114  that is configured for complementary engagement with a retention element  120 . The retention element  120  defines an inboard retention surface  121  that is configured to encircle the drive cable between the surface  121  and the interior portion  112  of the channel  110 . For the endmost bow assembly, the retention surface  121  may be configured to pinch or clamp the cable between the retention surface  121  and the interior portion  112 . For the other bow assemblies, the retention surface  121  may be configured to allow the cable to slide through the opening. The retention surface  121  and interior portion  112  may thus include a low-friction surface, similar to the low friction surface described above in relation to the surface  59  that slides along the top rail TR. 
         [0029]    As best seen in  FIG. 13 , the retention element  120  can have a cruciate shape, with side wings  122  and dovetail portions  123 . The retention opening  114  thus has a complementary cruciate shape to receive the retention element. The retention element is held within the channel  110  by a locking component  125 , which in one embodiment can include a washer  126  and screw  127  configured to be threaded into a bore  128  in the bow end body  104  above or below the side-opening channel  110 . The bore  127  may correspond to the bore  75  of the bow end  52  shown in  FIG. 6 , and the same fastener  127  may be used to fasten the tarp T to the bow end  100 , in the manner shown in  FIG. 7 . 
         [0030]    Returning to  FIG. 5 , the bow end body  54  may define an alignment bore  66  that can be used to align the bow ends for all of the bows in the cover system. In one use, the bow ends  52  are loosely engaged to corresponding bows and the bow ends are compressed in the cover retracted position. A rigid rod can be passed through the alignment bores  66  of the bow ends after which the bows can be fastened to the respective bow end. The bore  66  may also be used to accommodate accessories for use with the cover system. 
         [0031]    In a further aspect, the one-piece body  54  includes stabilization or hold-down features. The outboard portion  60  defines a stabilizing cable opening  67  at the base of the portion, as shown in  FIGS. 5-6 . The opening  67  receives a tensioning cable that is strung under tension from between the front and rear of the container body below the drive cable. This tension cable restricts upward movement of the bow end that might otherwise occur due to wind forces as the container is carried on the road. In one embodiment, the tension cable may be part of the drive cable that is wound around pulleys P at the opposite end of the container, as illustrated in  FIG. 1 . The drive cable thus includes an upper cable portion DC U  and a lower cable portion DC L , in which the upper cable portion extends through the bore  62  in the bow end. The lower cable portion DC L  passes through the stabilizing opening  67 . As illustrated in  FIG. 6 , the opening  67  is generally square or rectangular, providing significant clearance around the lower drive cable portion DC L . 
         [0032]    The stabilizing opening  67  is configured to limit the amount of pivoting or rotation of the bow end  52  that can occur as the cover system is extended or retracted. It is known that in certain conditions a particular bow assembly can pivot, tilt or rotate relative to the vertical, as depicted in  FIGS. 8-9 . When a bow assembly tilts it can bind against the top rail TR and jam the cover system, preventing it from deploying or retracting. It has been found that a bow assembly is less likely to bind if the amount of tipping or tilting is limited to less than about 30 degrees. Consequently, the present disclosure contemplates that the opening  67  may be configured so that the lower drive cable portion DC L  contacts the opposite edges  67   a ,  67   b  of the opening  67  at a point in which the bow end is tilted at less than about 30 degrees, as depicted in  FIG. 9 . Thus, as depicted in  FIG. 9 , even if the bow end  52  is tilted and the upper drive cable portion DC U  is tilted with the bow end, the interaction of the lower cable portion DC L  and the opening  67  prevents the bow end from tilting further, which can create the risk that the bow assemblies will bind during extension and retraction. 
         [0033]    In other installations, a tension strap is provided that traverses the top rail of the container. For these installations, the rod receiving portion  55  of the body  54  defines a stabilizing opening  68  for receiving a tension element. The stabilizing opening  68  is elongated generally parallel to the top rail TR and sized to receive a tension strap therethrough, such as tensioning strap ST, as depicted in  FIG. 6 . The ends of the strap ST may be anchored to the ends of the top rail TR or to a ratchet mechanism at one end to tighten the strap ST after it has been threaded through the opening  68  in all the bow ends  52 . The strap not only prevents lifting of the bow end, it also helps prevent the cover or tarp from folding underneath the bow or against the top rail. 
         [0034]    While the invention has been illustrated and described in detail in the drawings and foregoing description, the same should be considered as illustrative and not restrictive in character. It is understood that only the preferred embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the invention are desired to be protected.