Abstract:
A dual side tarp ( 10 ) is disclosed which allows the operator to shift the fixed tube of the tarp from one side of the trailer ( 12 ) to the other very quickly and efficiently to allow one side or the other of the trailer to be numbered to facilitate side dumping, for example. Use of pivoting tarp roll stop allows the shifting to be accomplished.

Description:
This is a division of U.S. patent application Ser. No. 09/952,488 filed Sep. 14, 2001, now U.S. Pat. No. 6,641,199. 

   TECHNICAL FIELD 
   This attention relates to trailers for carrying cargo and particularly to open top containers requiring a covering. 
   BACKGROUND OF THE INVENTION 
   Open top trailers are commonly used to carry cargo as diverse as wheat and topsoil. In recent years, many jurisdictions have required the use of a cover or a tarp over the open top of the trailer to prevent cargo from being blown from the trailer onto the highway, possibly endangering other motorists. Furthermore, operators have a financial interest in preventing loss of cargo as well. 
   A tarp cover has been developed which is commonly used in the industry. The cover includes a tarp with tubes secured at either side. One tube is permanently secured along one side of the trailer near the top. When the top is open for loading and unloading, the tarp is rolled up on the other tube with the movable tube adjacent the fixed tube. When the top is to be covered, the movable tube is rolled over the top of the trailer to the opposite side of the trailer and tightened against a ridge or ledge to secure the tarp over the top of the trailer. 
   While the conventional tarp cover is effective in many applications, it becomes an inconvenience when using a side dump trailer which can dump in either direction. A need exists to overcome this difficulty. 
   SUMMARY OF THE INVENTION 
   In accordance with one aspect of the present invention, an apparatus is provided for a trailer. The trailer has a first side and a second side. The apparatus includes a tarp having a first edge and a second edge with a first tube secured to the tarp at the first edge and a second tube secured to the tarp at the second edge. A first set of tarp roll stops is pivotally mounted to the trailer at the first side thereof, the first set of tarp roll stops pivotal between a raised position and a retracted position. A second set of tarp roll stops is pivotally mounted to the trailer at the second side thereof, the second set of tarp roll stops pivotal between a raised position and a retracted position. A first set of tarp keeper strips is mounted to the trailer at the first side and a second set of tarp keeper strips is mounted to the trailer at the second side. 
   When the tarp is to be opened toward the first side of the trailer, the first set of tarp roll stops is pivoted to the raised position, which secures the first tube to the trailer and permits the second tube to roll between the first side and second side of the trailer to cover and uncover the trailer. When the top is to be opened toward the second side of the trailer, the second set of tarp roll stops is pivoted to the raised position which secures the second tube to the trailer and permits the first tube to roll between the first side and second side of the trailer to cover and uncover the trailer. 
   In accordance with another aspect of the present invention, a tarp is provided for a trailer. The tarp has a first edge and a second edge. The tarp has an air chamber extending longitudinally parallel the first and second edges which can be inflated to stiffen the tarp. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete understanding of the invention and its advantages will be apparent from the following Detailed Description, taken in conjunction with the accompanying drawings, in which: 
       FIG. 1  is a side view of a trailer incorporating a first embodiment of the present invention illustrating a tarp being rolled open by a operator; 
       FIG. 2  is a side view of the trailer with the tarp in the closed position; 
       FIG. 3  is an end view of the trailer with the tarp stored for dumping to the roadside; 
       FIG. 4  is an end view of the trailer with the tarp stored for dumping to the curbside; 
       FIG. 5  is an end view of the trailer with the tarp in the closed position; 
       FIG. 6  is a detailed view of the trailer showing the tarp keeper strip; 
       FIG. 7  is a detail view of the front end of the trailer showing the tarp and air chamber; and 
       FIG. 8  is a plan view of a tarp forming a second embodiment of the present invention utilizing air chambers. 
   

   DETAILED DESCRIPTION 
   With reference now to the figures, there is disclosed a dual side tarp  10  forming a first embodiment of the present invention. The dual side tarp is utilized on a trailer  12  having an open top  14 . Trailer  12  is a side dump trailer which can be pivoted about axes  16  or  17  in either direction to dump the contents of the trailer to the roadside  18  or to the curbside  20  as desired. Trailer  12  can be used to carry grain, soil, or any other commodity desired. However, the dual side tarp  10  can be used on any trailer which would benefit from the design of the tarp  10 . 
   As will be described in greater detail hereinafter, the dual side tarp  10  permits the fixed portion of the tarp to be readily positioned on either side of the trailer  12 , as desired, while permitting the moveable portion of the tarp to be moved over the top  14  of the trailer to cover or uncover the top. This allows the operator to quickly change the side of the trailer unencumbered by the tarp to facilitate dumping on that side and prevent damage to the tarp. The dual side tarp  10  allows the fixed portion of the tarp to be quickly and easily changed from one side of the trailer to the other, allowing great flexibility in the use of the trailer  12 . 
   The trailer  12  defines a first elongate side  22  and a second elongate side  24 . The trailer also forms a front end  26  and a rear end  28 . Tarp roll stops  30  are pivotally mounted at each end of the trailer on both sides of the trailer. Each tarp roll stop  30  is pivotal for movement between a retracted position  32  and a raised position  34  as shown in  FIGS. 3 and 4 . Preferably, the tarp roll stops  30  can be pivoted by a tarp roll stop handle  36  activated by the operator  38 , but can alternatively be activated by a hydraulic mechanism or electric solenoid mechanism. 
   A tarp  40  is provided which is formed of conventional tarp materials. The tarp  40  defines a first edge  42  and a second edge  44 . The first edge  42  is secured along the length of a first tube  46 . The second edge  44  is secured along the length of a second tube  48 . At the rear end of each tube  46  and  48  is a receptacle to receive a universal joint  50 . 
   At least two tarp keeper strips  52  are mounted on each side of the trailer  12 . The tarp keeper strips  52  have a downwardly extending plate  54 . A front shelf  56  is mounted near the front end  26  of the trailer  12  and a rear shelf  58  is mounted near the rear end  28  of the trailer  12 . 
   The operator will decide in which direction the trailer  12  will be tipped, either in the roadside direction  18  or the curbside direction  20 . If tipping to the roadside, the tarp roll stops  30  on the second side  24  (the curbside) will be pivoted to the raised position  34 , while the tarp roll stops  30  on the first side will be pivoted to the retracted position  32 (as seen in FIG.  3 ). In the raised position, the tarp roll stops  30  will trap second tube  48  between the plates  54  of the tarp keeper strips  52  and the side  24  of the trailer  12  and prevent the second tube  48  from moving. The tarp  40  will extend upwardly from the second tube  48 . Meanwhile, the fist tube  46  is free to roll between the first side  22  and second side  24  of the trailer  12  on front and rear shelves  56  and  58  to cover and uncover the top  14  of the trailer  12 . When the top is open, the majority of the tarp  40  will be wrapped around the first tube  46 . When open, the first tube  46  can be wedged against the stop surfaces  60  of the tarp roll stops  30  on the second side  24  of the trailer  12 . The first tube  46  is wedged against the stop surfaces  60  by rotating a removable crank  62  attached to a joint  50  engaging the first tube  46 . As is conventionally known, the wedging action can be maintained by pivoting the removable crank about the U-joint  50  parallel the rear end  28  of the trailer  12 , as seen in  FIGS. 3-5 , and securing it in this position with a clamp  64 . 
   To cover the trailer  12 , the operator would free the removable crank  62  from clamp  64  and rotate the crank  62 , rolling the first tube  46  and tarp  40  over the top  14  of the trailer  12 . The first tube  46  rotates easily over the front and rear shelves  56  and  58  of the trailer  12 . When the first tube  46  is rolled to the fat side  22  of the trailer  12 , it is permitted to fall off the first side, as illustrated in  FIG. 6 , until the tarp  40  is completely unrolled from the first tube  46 . The operator continues to roll the tube  46  in the same direction, which causes the tarp  40  to start being rolled up on the first tube  46  in the opposite direction. The first tube  46  is caught by the plates  54  of the tarp keeper strips  52  on the first side  22  and wedged between the plates  54  and the first side  22  by the continued rotation of the tube  46 . The operator continues to rotate the tube  46  to achieve a desired tension in the tarp  40  over the top  14  of the trailer  12 . When this tension is achieved, the operator then pivots the removable crank  62  about the U-joint  50  to a position parallel the rear end  28  of the trailer  12  and secures the crank  62  to the clamp  64  so that the tarp  40  tightly covers the top of the trailer  12 . 
   When the load in the trailer  12  is to be dumped, the tarp  40  is rolled off the top  14  of the trailer  12  in a reverse operation to that described above. The operator releases the removable crank  62  from clamp  64  and begins to rotate the first tube  46  in the direction opposite the direction used when covering the top  14 . As the rotation proceeds, the first tube  46  disengages the plates  54  of the tarp keeper strips  52  and again hangs from the first side  22  until no portion of the tarp  40  is wrapped about the first tube  46 . As the rotation continues, the tarp  40  begins to be wrapped about the first tube  46  in the opposite direction. As the tube  46  continues to be rotated, the tube  46  rolls over the front and rear shelves  56  and  58  toward the second side  24  of the trailer  12 . Eventually, continued rotation forces the first tube  48  against the stop surfaces  60  of the tarp roll stops  30  on the second side of the trailer  12 . The tarp  40  is secured in this open position by again pivoting the removable crank  62  parallel the rear end  28  of the trailer  12  and securing the removable crank  62  in the clamp  64 . 
   If the operator  38  then determines that the next load should be dumped to the curbside, the dual side tarp  10  can be quickly and efficiently reconfigured from the position shown in  FIG. 3  to the position shown in FIG.  4 . To reconfigured the tarp  10 , the tarp roll stops  30  on the second side  24  of the trailer  12  are pivoted from the raised position  34  to the retracted position  32  shown in FIG.  4 . This frees the tubes  46  and  48  for movement from the second side  24  to the first side  22 . The first tube  46  is rotated as needed to unwrap any tarp  40  still wrapped thereon and is then placed between the plates  54  of the tarp keeper strips  52  and first side  22 . The tarp roll stops  30  on the first side  22  are then pivoted from the retracted position  32  to the raised position  34 , to secure first tube  46  between the first side  22  and the tarp keeper strips  52 . The second tube  48  can then be rolled over the top  14  of the trailer  12  with top  40  to cover and uncover the top of the trailer. When in the open position, the majority of the tarp  40  will be rolled around the second tube  48  which will be tightly urged against the stop surfaces  60  of the tarp roll stops  30  on the first side  22  by rotating the removable crank  62  as previously. In this position, the trailer  12  can be loaded, or tipped to the curbside direction for unloading. To cover the top  14 . the removable crank  62  is used to rotate the second tube  48  over the top  14  of the trailer  12  until the second tube  48  falls over the second side  24  to hang with no portion of the tarp  40  wrapped about the second tube  48 . As before, continued rotation of the second tube  48  will cause the tarp to begin to be wrapped about the second tube  48  in the opposite direction until the second tube  48  is caught between the plates  54  of the tarp keeper strips  52  on the second side  24  of the trailer  12  to tighten the tarp  40  on the top  14  of the trailer  12 . 
   As can be readily understood, the dual side tarp  10  can be quickly and efficiently reconfigured with the fixed tube  46  or  48  on whichever side is convenient for the direction of dumping. As noted, while the dual side tarp  10  is shown for use on a side dump trailer  12 , the dual side tarp  10  can be utilized on any trailer or other device where it could be useful. 
   With reference to  FIGS. 7 and 8 , a second embodiment of the present invention will be described. As can be seen, the tarp  40  has an air chamber or tube  80  extending along its longitudinal direction  82  and a series of lateral tubes  84  extending perpendicular to longitudinal direction  82 . Longitudinal direction  82  extends parallel the first and second elongate sides  22  and  24 . Each of the tubes  80  and  84  have an inflation valve  86  which allows pressurized air to enter the tubes  80  and  84  to inflate the tubes. When inflated, the tarp is stiffened by the inflated tubes  80  and  84 . This can allow the tarp to be used without bows over the top  14  of the trailer  12  to support tarp  40 , or can be used to supplement the use of bows, as desired. When the tarp  40  is to be rolled on first or second tubes  46  or  48 , the inflation valves  86  can be opened to empty the tubes  80  and  84  of air. If desired, the tarp  40  can have only a single tube  80  extending along its longitudinal direction  82 , without the use of lateral tubes  84 . 
   While several embodiments of the present invention have been illustrated in the accompanying drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangement, modifications and substitutions of parts and elements without departing from the scope and spirit of the invention.