Abstract:
A deployable trailer coving system includes spaced apart guide tracks mounted on opposite sides of a flat bed trailer. Each of the guide tracks support trolley assemblies support bows for movement along the length of the trailer. The bows support a trailer covering or tarp cover to define a cargo area. A tensioning mechanism is connected to at least one of the bows and applies a load to stretch the covering to a predetermined tension. The tensioning mechanism includes a torque-indicating tensioning actuator that produces one of an audible and a tactile sensation is produced when the predetermined level of tension in the covering is reached.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates in general to deployable trailer covering systems, such as can be used to create an enclosed cargo area on a flatbed trailer or the like. In particular, this invention relates to a deployable trailer covering system that may utilize a fabric tarp covering having an improved deployment mechanism that indicates when the desired deployed tension is achieved. 
         [0002]    Flatbed trailers are often used to haul loads that are bulky or heavy. These loads often have loading and unloading characteristics that rely on access to the open sides of the trailer for loading and unloading. Flatbed trailers provide open access for handling freight but lack a structure for conveniently covering the loads from the elements or for privacy. Tarps are often used to protect freight carried on a flatbed. Sometimes the tarps are applied directly over the loads to guard against the elements. Other flatbed covers rely on bows and other support structures to create a space over the trailer and support one or more tarp sheets. While these structures cover the flatbed trailer and create an enclosed freight hauling space, the structures are difficult or cumbersome to remove in order to gain side access of the trailer for freight handling. In addition, improper deployment of tarp structure may result in overloading or under-loading the covering, such as a fabric tarp covering, which may result in damage to the system. Overloading the tarp structure may result in bending the support bow system or tearing the fabric covering. Under-loading the tarp structure causes the fabric to wrinkle or otherwise fail to be taut. This condition allows the fabric to flap in response to air pressure and wind. As the fabric moves relative to the support structure, excessive wear occurs causing damage to the covering and potentially the cargo inside. Thus, it would be desirable to provide an mechanism to indicate when the tarp system has been properly deployed. 
       SUMMARY OF THE INVENTION 
       [0003]    This invention relates to a deployable trailer covering system having a torque responsive deployment mechanism. These deployable trailer covering systems may include a rigid covering or a fabric covering. In a particular embodiment, this invention relates to a fabric based trailer tarp covering system that is deployed by a torque generating device that indicates when the proper load has been applied to deploy the system. 
         [0004]    The torque generating device may be in the form of an offset crank handle having a torque indicating capability that produces one of an audible and tactile sensation that alerts a user when the desired or proper tension has been imparted to the fabric trailer cover. This tension level is associated with the torque to actuate the tarp covering system and may be set as a predetermined torque level or may be an adjustable torque level that is set in response to the type of fabric covering used. 
         [0005]    Various aspects of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a perspective view of a flatbed trailer with a deployable trailer covering system in accordance with this invention. 
           [0007]      FIG. 2A  is an enlarged perspective view of a portion of the flatbed trailer and deployable trailer covering system of  FIG. 1 . 
           [0008]      FIG. 2B  is an enlarged view of a tarp tensioning mechanism, including an embodiment of a torque indicating tensioning actuator, that is part of the deployable trailer covering system of  FIG. 1 . 
           [0009]      FIG. 3  is an exploded view of the embodiment of the torque-indicating tensioning actuator of  FIG. 2B . 
           [0010]      FIG. 4A  is an enlarged, perspective view of a torque-responsive, indicating mechanism in a neutral position. 
           [0011]      FIG. 4B  is an enlarged, perspective view of the torque-responsive, indicating mechanism in a position indicating that the desired torque level has been achieved. 
           [0012]      FIG. 5A  is an elevational view of another embodiment of a torque indicating tarp tensioning actuator in accordance with the invention. 
           [0013]      FIG. 5B  is a cross sectional side view of the torque indicating tarp deployment actuator taken along line  5 B- 5 B. 
           [0014]      FIG. 5C  is a cross sectional end view of the torque indicating tensioning actuator taken along line  5 C- 5 C. 
           [0015]      FIG. 6  is yet another embodiment of a torque indicating tensioning actuator in accordance with the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0016]    Referring now to the drawings, there is illustrated in  FIGS. 1, 2A and 2B  a flatbed trailer, shown generally at  10 , that is covered by a deployable trailer covering system, shown generally at  20 . The deployable trailer covering system  20  includes a plurality of bows including a front bow  22 , a plurality of intermediate bows  24 , and a rear bow  26 . A tarp covering  28  can be attached between the respective bows  22 ,  24 , and  26  or, alternatively, a single tarp can be stretched along a length of the flatbed trailer  10 . The ends of the bows  22 ,  24 , and  26  are supported on a rolling track system, shown generally at  30 , that is provided on opposite sides of the flatbed trailer  10 . Thus, the deployable trailer covering system  20  can be extended along a deck of the flatbed trailer  10  to create an enclosed cargo area or can be retracted when not in use. Although the deployable trailer covering system  20  is illustrated for use with a flatbed trailer  10 , it should be appreciated that the tarp system  20  can be used in any desired environment and for any desired purpose. For example, in addition to the trucking industry, the deployable trailer covering system  20  may also be used in the rail and shipping industries or any other industry. 
         [0017]    The rolling track system  30  includes a pair of guide tracks  32  that respectively extend along opposite sides of the flatbed trailer  10 . The guide tracks  32  form channels that accept trolley assemblies  34 . The guide tracks and trolleys are similar to those disclosed in U.S. Patent Publication No. 2013-0249237 A1, the disclosure of which is incorporated herein by reference in its entirety. The trolley assemblies  34  are configured to roll or otherwise translate relative to the guide tracks  32 . The trolley assemblies  34 , located on opposite sides of the trailer  10 , are interconnected by a bow element  36  to form the various bows  22 ,  24 , and  26 . At least one of the trolley assemblies  34  is attached to a tensioning mechanism, shown generally at  40 . In the illustrated embodiment, the tensioning mechanism  40  includes a tensioning head  42  having a torque transmitting drive unit  44  and a reaction end  46 . An actuator  48 , such as an ACME screw, pulley and cable system, hydraulic pump, or any other suitable mechanism configured to move the attached trolley assembly  34  relative to the guide tracks  32 , is connected between the tensioning head  42  and the reaction end  46 . Movement of the trolley assemblies  34  by the tensioning mechanism  40  causes the plurality of intermediate bows  24  to move along the guide tracks  32  and tension the tarp covering  28  when the front bow  22  is fixed relative to the guide tracks  32 . 
         [0018]    In the illustrated embodiment, the tensioning mechanism is illustrated as an A-frame tensioning mechanism, having first and second support legs  50  and  52  that connect the tensioning head  42  and the reaction end  46 , respectively, to the rear bow  26  by a junction point  54 . As the torque transmitting drive unit  44  is rotated, the ACME screw thread actuator  48  drives the tensioning head  42  and the reaction end  46  relative to the trailer  10 . The junction point  54  is detachably connected to the rear bow  26 . As rotation of the ACME screw actuator  48  causes the support legs  50 ,  52  and junction point  54  to move the rear bow  26  along the guide track  32 , the tarp covering  28  becomes taut. During the tarp tensioning procedure, the tensioning head  44  is rotated by a torque-indicating tensioning actuator, shown generally at  56 . 
         [0019]    Referring now to  FIG. 3 , the torque-indicating tensioning actuator  56  is illustrated as an offset crank configuration, though any suitable torque transmitting configuration may be used. The torque-indicating tensioning actuator  56  includes a handhold end, shown generally at  58 , and a driving end, shown generally at  60 . The driving end  60  is configured to mate with the tensioning head  44  such that the tensioning mechanism  40  can be actuated. The handhold end  58  includes a grip  62  and a drive connection  64 . The drive connection  64  may be permanently fixed to or detachably fixed to a torque-responsive, indicating assembly, shown generally at  66 . The torque-responsive, indicating assembly  66  includes an outer member  68 , illustrated as a hollow, tubular section, that receives torque inputs and rotary motion from the handhold end  58  and transmits them to the driving end  60  and then to the tensioning head  44 . The outer member  68  and the drive connection  64  are attached at a first end  68   a  such that torque is transmitted from the handhold end  58  to the driving end  60  through the outer member  68 . The outer member  68  accepts the drive connection  64  as either a permanently fixed attachment (i.e., a connection that is not intended to be separated once assembled) or a detachably fixed attachment. In general, the attachment of the drive connection  64  to the outer member  68  is torque transmitting and stable in bending so as not to permit substantial bending movement between the handhold end  58  and the torque-responsive, indicating assembly  66  during use. 
         [0020]    The outer member  68  is pivotally connected at a second end  68   b  to a torque reaction beam, shown generally at  70 . The torque reaction beam  70  is pivotally connected at a fulcrum point  72 , illustrated as a spherically shaped pivot point that is received within the outer member  68 . The fulcrum point  72  includes a fulcrum mounting aperture  74  that aligns with an outer member aperture  76 . The aligned apertures  74  and  76  accept a connection element  78 , illustrated as a dowel. The connection element may be any suitable structure such as a roll pin, bolt, rivet, and the like. The torque reaction beam  70  includes a reaction arm  80 . The reaction arm  80  includes a biasing stop  82  that prevents a rocking or toggling motion of the reaction arm  80  within the outer member  68  when torque is applied in one direction, but permits motion when torque is applied in the other direction. The reaction arm  80  further includes a first reaction notch  84  that defines a first end of a torque-responsive, indicating mechanism, shown generally at  100  in  FIGS. 4A and 4B . 
         [0021]    A torque sensitive biasing assembly  86  is positioned within the outer member  68  between the first end  68   a  and the reaction arm  80  at the second end  68   b . The torque sensitive biasing assembly includes a stop  88  that may be fixed within the outer member  68 . In one embodiment, the stop  88  is a threaded member that is adjustable to set a spring tension set point of a biasing spring  90 . Alternatively, the stop  88  may be a press fit attachment or a pinned attachment to the outer member  68 . The biasing spring  90  applies an axial load L against a reaction plug  92 , that has a second reaction notch  94 . The first and second reaction notches  84  and  94  are generally “V”-shaped and include a flat region  94   c  between V-shaped walls  94   a  and  94   b . In one embodiment, the second reaction notch  94  includes a wider V-shaped notch, though the wider notch may be applied to the first reaction notch  84 . A pivot pin  96  mates with the first and second reaction notches  84  and  94 . The pivot pin  96  is generally rectangular in shape and includes ends  98  that are configured to rotate within the outer member  68 . In the illustrated embodiment, the ends  98  are illustrated as pins that extend from the pivot pin  96  to the inner surface of the outer member  68 . Alternatively, the ends may be spherical in shape. 
         [0022]    The torque reaction beam  70  further includes a receiver end  102  that couples the driving end  60  to the outer member  68 . The receiver end  102  may include an aperture  104  that mates with a similarly shaped mounting end  106  of the driving end  60 . In the illustrated embodiment, the mating end  106  and aperture  104  are configured similarly to a conventional ratchet wrench and socket connection, though any suitable shape may be used. Alternatively, the receiver end  102  may be integrally formed with the driving end  60 , if so desired. 
         [0023]    Referring now to  FIGS. 4A and 4B , when a torque is applied to the torque-responsive, indicating assembly  66  as the handhold  58  is cranked, a bending moment M reacts at the fulcrum point  72  such that the reaction arm  80  toggles within the outer member  68 . Movement of the reaction arm  80  is resisted by the axial load L applied to the reaction plug  92  that presses the pivot pin  96  against the first and second reaction notches  84  and  94 . When the magnitude of the bending moment M is sufficient to overcome the axial load against the pivot pin  96 , the pin  96  and the reaction arm  84  snap laterally within the outer member  68 , as shown in  FIG. 4B . This lateral motion, or toggling motion, causes at least one of an auditory and tactile sensation that indicates a preset torque level, which is a function of the axial force L. has been achieved. The axial load L is set by the amount of compression exerted on the biasing spring  90 . The torque level is chosen such that the tarp covering  28  becomes taut to eliminate flapping or other wear-creating movements yet not so tight that the material will tear or excessive wear and load is imparted to the trolley assemblies  34  and the guide tracks  32 . The compression of the biasing spring  90  may be adjustable within a range of values or fixed to a singular value. 
         [0024]    Referring now to  FIGS. 5A, 5B, and 5C , there is illustrated another embodiment of a torque-indicating tensioning actuator, shown generally at  156 . The torque-indicating tensioning actuator  156  includes a handhold end  158  and a driving end  160 . An adjustable torque-responsive, indicating assembly is shown generally at  162 . As shown in  FIGS. 5B and 5C , the adjustable torque-responsive, indicating assembly  162  includes a torque level adjusting sleeve  164  that is fixed axially relative to the handhold  158  but free to rotate relative thereto. The torque level adjusting sleeve  164  may be axially retained by a groove  158   a  or flange arrangement, as part of the handhold  158 , that traps a retaining flange  164   a  defining a retaining end that closes around the handhold  158 . The torque level adjusting sleeve  164  includes a threaded inner diameter  166 . A spring bias sleeve  168  is disposed within the torque level adjusting sleeve  164  and includes a threaded outer diameter  170  that engages the threads within the adjusting sleeve  164 , such that rotation R of the adjusting sleeve  164  causes axial movement A of the biasing sleeve. The biasing sleeve  168  further includes a spring seat  172  configured generally as an annular flange that permits a shaft portion  164   a  of the driving end  164  to extend therethrough. 
         [0025]    A biasing spring  174  is disposed within the biasing sleeve  168  and around the shaft portion  160   a  of the driving end  160 . One end of the biasing spring  174  abuts the spring seat  172 . The opposite end of the biasing spring  174  abuts a torque-responsive, indicating assembly, shown generally at  176 . The torque-responsive indicating assembly  176  includes first and second abutting load disks  178  and  180  and at least one indicating ball  182  disposed therebetween. The illustrated embodiment shows two indicating balls  182  spaced 180 degrees apart, though any suitable number may be provided. Typically the indicating balls  182  may be evenly spaced between the load disks  178  and  180 , though such is not required. As shown in  FIGS. 5B and 5C , load disk  178  includes torque pockets  184  that face corresponding torque pockets  186  formed in the load disk  180 . The torque pockets  184  and  186  are illustrated having a generally sinusoidal shape that traps the indicating ball  182 . The torque pockets  184  and  186  further define peaks  188  and  190  adjacent to the ball  182 . 
         [0026]    As the torque level adjusting sleeve  164  is rotated relative to the spring biasing sleeve  168 , the biasing spring is compressed or relaxed against the mating load disks  178  and  180 . The magnitude of axial force against the load disks  178  and  180  determines the torque level required to compress the biasing spring  174  and cause the ball  182  to snap over the peaks  188  and  190 . The snapping action of the ball  182  provides at least one of an auditory and a tactile sensation to alter the user that the proper torque level and tarp tension has been achieved. 
         [0027]    Referring now to  FIG. 6 , there is illustrated an embodiment of a torque-indicating tensioning actuator, shown generally at  200 . The torque indicating tensioning actuator  200  includes an adjustable torque-responsive, indicating assembly, shown generally at  262  which is similar in construction and operation to the adjustable torque-responsive, indicating assembly  162 , described above. The torque indicating tensioning actuator  200  is part of a tensioning head  244 , that is similar to tensioning head  44 , described above. In this embodiment, the ability to produce a torque sensitive reaction that provides an auditory or tactile sensation that the torque level and tarp tension has been achieved is provided in the tensioning mechanism attached to the flatbed trailer. Thus, any suitable handle may be used to apply the necessary torque and rotary motion to tension the tarp assembly. 
         [0028]    The principle and mode of operation of this invention have been explained and illustrated in its preferred embodiment. However, it must be understood that this invention may be practiced otherwise than as specifically explained and illustrated without departing from its spirit or scope.