Abstract:
An apparatus to assist tightening of cargo straps used on flat-bed vehicles comprises a gearbox having a worm gear and matching wheel gear to tighten the strap. The output of the gearbox is coupled to a tie-down strap. The apparatus enables a user to quickly and properly tighten a tie-down strap regardless of the user&#39;s physical size and strength. The apparatus can be provided at each tie-down strap or be moved from strap location to strap location as desired.

Description:
RELATED APPLICATIONS 
     The present invention was first described in and claims the benefit of U.S. Provisional Application No. 61/322,269 filed May 7, 2010, the entire disclosure of which is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present invention relates generally to tie-down assemblies for cargo straps, and in particular, to a portable gear ratchet mechanism used to tighten and secure cargo straps. 
     BACKGROUND OF THE INVENTION 
     Load straps are a common tool in the trucking industry. They are used to secure loads, primarily on flat bed trailers of tractor-trailer rigs. Load straps are useful because they readily adapt to any size load and securely hold those loads over long distances, such as across interstate highways. However, as with most mechanical items, they must be properly used to be effective. 
     When load straps are not installed sufficiently tightly, the cargo can move about and sometimes even fall from the truck. Many drivers use a bar to tighten load straps in their bracket. However, this is a time consuming process because the bar must be repeatedly inserted and removed in the tightening process. This excessive time sometimes causes users to not properly apply the straps in an effort to save time. Even when done properly, many truck drivers with diminished strength or those who are slightly disabled cannot apply enough pressure to correctly tension the straps. 
     Various attempts have been made to provide winch-type assisting mechanisms for installing and tightening load straps. Examples of these attempts can be seen by reference to several U.S. patents, such as U.S. Pat. No. 5,433,565; U.S. Pat. No. 5,791,844; U.S. Pat. No. 6,719,507; U.S. Pat. No. 6,729,604; U.S. Pat. No. 7,108,246; and U.S. Pat. No. 7,469,916. However, none of these designs are similar to the present invention. 
     While these apparatuses fulfill their respective, particular objectives, each of these references suffer from one (1) or more of the aforementioned disadvantages. Many such apparatuses are difficult to install. Many such apparatuses do not work easily with external load straps. Many such apparatuses do not adequately secure the load strap once installed and can come loose during use. Many such apparatuses are difficult to tighten. Many such apparatuses can become stuck or tangled easily during use. Accordingly, there exists a need for a mechanism to assist in the installation, tightening, and securement of load straps without the disadvantages as described above. The development of the present invention substantially departs from the conventional solutions and in doing so fulfills this need. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing references, the inventor recognized the aforementioned inherent problems and observed that there is a need for a mechanism to assist in the installation, tightening, and securement of load straps in a manner which is simple, safe, and easily operated without need for excessive physical exertion and which is further simple to uninstall after use in order to unload cargo. Thus, the object of the present invention is to solve the aforementioned disadvantages and provide for this need. 
     To achieve the above objectives, it is an object of the present invention to provide increased mechanical advantage for the installation and tightening of cargo tie-downs or straps. The apparatus is particularly adapted for use with a tractor trailer or similar vehicle, with a desired plurality of the apparatuses being installed and utilized simultaneously. The apparatus includes a case, a take-up roll that receives a strap, a worm gear to adjust the take-up roll, and a ratchet locking mechanism to secure the tightened strap during transport. 
     Another object of the present invention is to removably fasten to a vehicle with a plurality of fastening members. In the preferred embodiment, the fastening members are a plurality of threaded apertures that enable a user to screw the apparatus against a side of a truck bed. 
     Yet still another object of the present invention is to construct the apparatus of weather-resistant metal or another weather-resistant material to enable semi-permanent use on a particular exposed truck bed over a prolonged period. 
     Yet still another object of the present invention is to securely receive and retain an end of a load strap through an axial slot in the take-up roll. The take-up roll can then be rotated in order to wind and tighten the strap. 
     Yet still another object of the present invention is to include a guide roll adjacent the take-up roll which directs the strap into the axial slot and helps to prevent tangling or unwanted motioning of the strap during transport. 
     Yet still another object of the present invention is to provide mechanical assistance for winding the take-up roll using a worm gear and wheel gear mechanism. The wheel gear is affixed to the take-up roll and housed within the case. The worm gear is a spiral-threaded cylindrical gear with a plurality of teeth engaging the wheel gear. The high gearing ratio between the worm gear and wheel gear provides a higher mechanical advantage than the common method of applying a lever device onto a separate ratchet mechanism. 
     Yet still another object of the present invention is to facilitate turning of the worm gear with a manual hand crank. The hand crank includes an input drive that removably engages an extension drive end portion of the worm gear. A user can engage the input drive with the extension drive, grip a handle of the hand crank, and rotate the handle to wind the worm gear, wheel gear, and take-up strap in a comfortable and assisted manner. 
     Yet still another object of the present invention is to automatically lock the take-up roll and thereby secure the strap when in a tightened state with an integral ratchet wheel and pawl. The ratchet wheel is affixed to the take-up roll and the pawl prevents unwinding of the ratchet wheel and take-up roll. The user can manually lift the pawl upward to disengage the pawl from the ratchet wheel as desired, such that the take-up roll and strap can be loosened for removal after use. 
     Yet still another object of the present invention is to provide a method of utilizing the device that provides a unique means of installing one (1) or more of the apparatus on a vehicle, installing an open end of a strap into an axial slot of a take-up roll, engaging the extension drive with the input drive of the crank, rotating the crank to cause the worm gear rotate and concurrently drive the wheel gear and the take-up roll to tighten the strap, removing the crank at the end of the tightening procedure, repeating for each strap and apparatus, and lifting a ratchet pawl to enable a ratchet wheel to disengage the strap from the take-up roll as desired. 
     Further objects and advantages of the present invention will become apparent from a consideration of the drawings and ensuing description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages and features of the present disclosure will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which: 
         FIG. 1  is an environmental view of a plurality of portable gear ratchet actuators  10  installed onto a vehicle  62 , according to a preferred embodiment of the present invention; 
         FIG. 2  is a front perspective view of the portable gear ratchet actuator  10 , according to a preferred embodiment of the present invention; 
         FIG. 3  is a side perspective view of the portable gear ratchet actuator  10  depicting a partially removed surface, according to a preferred embodiment of the present invention; 
         FIG. 4  is an opposing side perspective view of the portable gear ratchet actuator  10 , according to a preferred embodiment of the present invention; 
         FIG. 5   a  is a bottom perspective view of the portable gear ratchet actuator  10 , according to a preferred embodiment of the present invention; 
         FIG. 5   b  is another bottom perspective view of the portable gear ratchet actuator  10  depicting a magnet  70 , according to a preferred embodiment of the present invention; and, 
         FIG. 5   c  is yet another bottom perspective view of the portable gear ratchet actuator  10  depicting a spring clamp  75 , according to a preferred embodiment of the present invention. 
     
    
    
     DESCRIPTIVE KEY 
     
         
         
           
               10  portable gear ratchet actuator 
               11   a  case 
               11   b  aperture 
               12  worm gear 
               13  wheel gear 
               14  worm extension 
               15  extension drive 
               16   a  take-up roll 
               16   b  axial slot 
               17  ratchet wheel 
               18   a  ratchet pawl 
               18   b  ratchet pawl axle 
               19  guide roll 
               20  crank 
               21  input drive 
               22  handle 
               30  fastening member 
               31  fastening aperture 
               61  strap 
               62  vehicle 
               63  freight cover 
               70  magnet 
               75  spring clamp 
           
         
       
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In accordance with the invention, the best mode is presented in terms of a preferred embodiment, herein depicted within  FIGS. 1 through 5   c . However, the disclosure is not limited to a single described embodiment and a person skilled in the art will appreciate that many other embodiments are possible without deviating from the basic concept of the disclosure and that any such work around will also fall under its scope. It is envisioned that other styles and configurations can be easily incorporated into the teachings of the present disclosure, and only one particular configuration may be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. 
     The present invention describes a portable gear ratchet actuator (herein described as the “apparatus”), which provides a means for increasing a mechanical advantage in the installation of cargo ties-down or straps  61 . 
     Referring now to  FIG. 1 , an environmental view of a plurality of the apparatuses  10  installed onto a vehicle  62 , according to the preferred embodiment of the present invention, is disclosed. The vehicle  62  utilized is preferably a tractor trailer or the like which further utilizes a freight cover  63  to protect the load being transported. The freight cover  63  is secured via a plurality of straps  61  and the apparatus  10  assists in fixing said straps  61  firmly against the load. 
     Referring now to  FIG. 2 , a front perspective view of the apparatus  10 , according to the preferred embodiment of the present invention, is disclosed. The apparatus  10  comprises an integral locking ratchet mechanism which is enclosed within a six-sided rectangular case  11   a . The case  11   a  is approximately six (6) inches square and preferably fabricated from materials such as a weather resistant metal, a durable plastic, or the like. The case  11   a  encloses a worm gear  12  in mechanical communication with a wheel gear  13  (see  FIG. 3 ) which rotate a take-up roll  16   a  to tighten or loosen the strap  61 . The case  11   a  comprises an aperture  11   b  which partially spans across front and upper sides of said case  11   a  to provide access to the take-up roll  16   a  and a guide roll  19  for placement of a strap  61 . The take-up roll  16   a  comprise an axial slot  64  designed to firmly capture an end of the strap  61 , while the guide roll  19  keeps the strap  61  aligned with the take-up roll  16   a . The axial slot  64  comprises a length greater than the length of common straps  61  to enables placement within. A clockwise rotation of a crank  20  causes the wheel gear  13  (see  FIG. 3 ), and thereby the take-up roll  16   a , to rotate in a counterclockwise direction. With the strap  61  guided to pass under the guide roll  19  and over the take-up roll  16   a , the counterclockwise rotation develops an increasingly tightening load onto the captured strap  61 . The guide roll  19  is rotatably attached to opposing inside surfaces of the aperture  11   b  portion of the case  11   a  and positioned slightly behind and above the take-up roll  16   a  and utilized to guide the strap  61 . The take-up roll  16   a  and guide roll  19  are preferably fabricated from materials similar to the case  11   a . The apparatus  10  also comprises a digit-operated hand crank  20  (also see  FIG. 3 ) which enables the user to activate the worm gear  12  to further tighten the strap  61 . 
     Referring now to  FIG. 3 , a side perspective view of the apparatus  10 , according to the preferred embodiment of the present invention, is disclosed. A front surface of the case  11   a  (also see  FIG. 2 ) also comprises a worm extension  14  further comprising an extension drive  15  which enables insertion of the abovementioned crank  20  for tightening of the strap  61 . The worm extension  14  is a distal portion of the worm gear  12  and is rotated by means of the crank  20  which comprises an input drive  21  and a handle  22 . The input drive  21  and the handle  22  are both integral members of the crank  20  wherein the input drive  21  comprises a profile which is able to engage the extension drive  15  and the handle  22  provides a feature for the user to grasp during use. The crank  20  is fabricated from materials such as, but not limited to: metal, plastic, or the like. 
     Engaging the input drive  21  of the crank  20  into the extension drive  15  and moving said crank  20  in a circular direction causes the worm gear  12  to rotate, whereby the helical action of said worm gear  12  imparts a rotary motion onto the wheel gear  13  and concurrently to the integral take-up roll  16   a . As illustrated herein the worm gear  12  comprises a cylindrical-shape further comprising a plurality of spiraled threads upon the exterior surface which mesh with a plurality of teeth upon the perimeter edge of the disc-shaped wheel gear  13  to drive said wheel gear  13  and take-up roll  16   a . The take-up roll  16   a  is located and fixed to an intermediate portion of the wheel gear  13  which suspends said wheel gear  13  and engages said wheel gear  13  with the worm gear  12 . Since the worm gear  12  comprises a high gearing ratio between the wheel gear  13 , engaging the apparatus  10  provides a user with a significantly higher mechanical advantage than the normal application of a lever device onto the separate ratchet mechanism. 
     Referring now to  FIG. 4 , an opposing side perspective view of the apparatus  10 , according to the preferred embodiment of the present invention, is disclosed. Additionally, the apparatus  10  comprises an integral ratchet wheel  17  and a ratchet pawl  18   a  which enables the apparatus  10  to lock the take-up roll  16   a  and secure the strap  61  in a tightened position. The interaction between the worm gear  12  and the wheel gear  13  is non-reversing; therefore, the interaction of the ratchet wheel  17  and the ratchet pawl  18   a  provide an additional measure of protection against an accidental loosening of the tension generated within the strap  61 . The ratchet wheel  17  is fastened to a side of the case  11   a  opposing and parallel to the wheel gear  13  via a common fastener inserted through said case  11   a  and into the take-up roll  16   a , thereby enabling said ratchet wheel  17  to rotate concurrently with said take-up roll  16   a . The ratchet wheel  17  is disc-shaped and comprises a plurality of asymmetric and gently sloped teeth upon the entire exterior surface which are engaged by the ratchet pawl  18   a . The ratchet pawl  18   a  comprises a “J”-shape and is attached above the ratchet wheel  17  via a spring-loaded ratchet pawl axle  18   b  which is further fastened to the side surface of the case  11   a . The ratchet pawl axle  18   b  enables the ratchet pawl  18   a  to pivot and slide over the teeth of the ratchet wheel  17  which engages a space between said teeth as said ratchet wheel  18   b  rotates in a clockwise direction. The ratchet wheel  17  is unable to rotate in a counterclockwise rotation because the ratchet pawl  18   a  catches the teeth of said ratchet wheel  17  which locks said ratchet pawl  18   a  against the tooth of said ratchet wheel  17  and prevents any further motion in that direction. The ratchet pawl  18   a  must be lifted upwardly, thereby disengaging said ratchet pawl  18   a  from the ratchet wheel  17  and enabling the take-up roll  16   a  to rotate and further remove the strap  61  from the apparatus  10 . 
     Referring now to  FIG. 5   a , a bottom perspective view of the apparatus  10 ,  5   b , another bottom perspective view of the apparatus  10  depicting the magnet  70 , and  FIG. 5   c , yet another bottom perspective view of the apparatus  10  depicting the spring clamp  75 , according to the preferred embodiment of the present invention, are disclosed. A rear surface of the apparatus  10  comprises a fastening member  30  which provides a means of removably fastening said apparatus  10  onto the structure of the vehicle  62 . The fastening member  30  is depicted herein as including a pair of fastening apertures  31  which are preferably threaded upon an interior diameter and engaged by a pair of common threaded fasteners such as threaded screws. The fastening member  30  may utilize other fastening means such as, but not limited to: a permanent magnet  70  (see  FIG. 5   b ), a spring clamp  75  (see  FIG. 5   c ) or the like. 
     It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the apparatus  10  it would be installed as indicated in  FIG. 1 . 
     The method of utilizing the apparatus  10  may be achieved by performing the following steps: covering the loaded vehicle by installing the freight cover  63 ; selecting the appropriate load tie-down straps  61 ; fastening a dead-end of each strap  61  onto a member of one (1) side rail of the vehicle  62 ; passing the strap  61  over the top portion of the covered cargo toward the opposite side of vehicle  62 ; installing the open end of each strap  61  into a corresponding axial slot  16   b  upon the take-up roll  16   a ; fastening each existing ratchet mechanism onto the opposite side rail of the vehicle  62  via attaching the fastening member  30  thereto; engaging the extension drive  15  within the worm extension  14  with the input drive  21  upon the crank  20 ; rotating the crank  20  to cause the worm gear  12  to rotate and concurrently drive the wheel gear  13  which simultaneously rotates the take-up tool  16   a  to tighten the strap  61 ; removing the crank  20  at the end of the tightening procedure; proceeding to the next desired location of the apparatus  10 ; repeating the tightening procedure at the location of each apparatus  10 ; lifting the ratchet pawl  18   a  to enable the ratchet wheel  17  to rotate in a free counterclockwise rotation to disengage the strap  61  from the take-up roll  16   a  as desired; and, utilizing the apparatus  10  to load straps  61  upon vehicles  62  more quickly and more safely. 
     The method of removably attaching each apparatus  10  to the vehicle  62  can be accomplished via the preferred fastening embodiment  30 , but may otherwise be attached via the magnetic fastener embodiment  70  or the spring clamp embodiment  75 . 
     The foregoing descriptions of specific embodiments have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Various modifications and variations can be appreciated by one skilled in the art in light of the above teachings. The embodiments have been chosen and described in order to best explain the principles and practical application in accordance with the invention to enable those skilled in the art to best utilize the various embodiments with expected modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the invention.