Patent Publication Number: US-2022212906-A1

Title: Self-retractable winch

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from U.S. provisional patent application 63/133,259 filed Jan. 1, 2021, the specification of which is hereby incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to the field of cargo securing winches for the transport industry. Specifically, the present invention relates to self-retracting winches, binders and other webbing and cable binders using similar systems mainly used but not limited to secure cargo on transport vehicles beds. 
     BACKGROUND OF THE INVENTION 
     Securing cargo on trucks beds and trailers are a standard that remained unchanged for decades using winches, winding and binding webbing or cable, therein referred as tie down media, on sides of the truck or trailer bed or other vehicles to secure the cargo. Once the cargo is removed the operator has to rewind the webbing or cable. Nowadays, the rewinding process has been done by hand or using a crank. The process is time consuming and repetitive movements may be a source of injuries to the operators. Recently, diverse adaptors allow the use of a battery powered drill to accelerate the rewinding process came on the market. These adaptors may attract other kind of problems caused by sudden blockage on the winch at high speed causing the drill to kick or from a whipping action of the tie down media, caused by a too fast winding, leading to other injuries. Furthermore, a battery-operated device that need to be moved at each winch, will need more maintenance and has a higher risk of failure. Some self-retracting winches were designed and marketed. The operators deemed them impractical because of the constant retracting tension that did not allowed them to move the tie down media freely on and over the cargo. It often needed two operators to manage the cargo-tying process. Therefore, there is a need for a self rewinding winch, that may be blocked in a partial un-winded position, reliable, that is not depending on adding another tool that can be lost or forgotten and providing a more controllable rewinding process. 
     SUMMARY OF THE INVENTION 
     The present invention includes many aspects and features. The aforesaid and other objectives of the present invention are realized by generally providing a self-retracting cargo winch apparatus and method of use thereof. 
     The cargo tie down winch includes a rewinding module to improve the rewinding operation time and safety. This apparatus can be locked or deactivated at given lengths in order to have a tension free tie down media. 
     At least one aspect of the present invention provides self-retracting tie down winch apparatus with a locking mechanism that prevents the rewinding process to engage at any given extension on the tie down media. 
     At least one aspect of the invention provides standard cargo tie down winch equipped with a self-retracting apparatus with a locking mechanism offering a plurality of states exemplified as follows. Firstly, for instance, an unwinding state where no locking occurs, and the recoil spring is gaining tension. Secondly, a locking state where the unwinding is stopped, the rewinding state is blocked but an unwinding state may be obtained if needed. Thirdly, a free state where the tie down media can either go in unwinding or rewinding/retracting state. And last, a rewinding state where the tie down media is retracted on the apparatus and spooled on the winch shaft by the release of the recoil spring tension. 
     At least one aspect of the invention provides a management of the different states only by pulling and releasing the tie down media. 
     At least one aspect of the invention where a separate mechanism is in place to bind the tie down media in order to secure the cargo on the bed of the transport vehicle. 
     At least one aspect of the invention where the binding mechanism is disposed at the opposite side of the rewinding mechanism. 
     At least one aspect of the invention provides friction limiting components to reduce overall frictions and increase efficiency of the rewinding process. 
     At least one aspect of the invention provides a sealed enclosure for the rewinding components. 
     At least one aspect of the invention provides a sealed enclosure for the rewinding spring and locking mechanism. 
     At least one aspect of the invention provides a standard hookup to the transport vehicle&#39;s frame. 
     At least one aspect of the present invention provides means of securing many apparatuses together in a ganging manner for transport when not in use. 
     At least one aspect of the invention provides a tie down media retaining system in order to prevent the tie down media to exit the winch. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch for securing a cargo on a vehicle, including: a frame for mounting to the vehicle; a shaft rotatably mounted to the frame adapted to receive a tie down media to be used to secure the cargo, the tie down media being adapted to be wound around the shaft, and urging rotation along with the shaft when the tie down media is wound or unwound; a biasing means fixedly mounted to the shaft, the biasing means being anchored to the frame; wherein upon unwinding the tie down media, rotation of the shaft loads the biasing means, and wherein load accumulated in the biasing means helps rewind the tie down media around the shaft. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, further including a control mechanism able operate in at least two states, including one preventing the tie down media to wind, and one allowing the tie down media to rewind freely under the load accumulated in the biasing means. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the control mechanism includes a toothed gear and a biased pawl cooperating with the toothed gear. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein toothed gear including a first tooth-free part separating two teethed parts. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein toothed gear including a second first tooth-free part separating the two teethed parts. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein biased pawl has an abutting extremity adapted to penetrate between neighbor teeth of the toothed gear, a second extremity connected to a pawl-biasing means, and a rotation axis located between the abutting extremity and the second extremity. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein biased pawl includes a rounded back face. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the biased pawl has an abutting extremity and wherein the rounded back face has a radius of curvature allowing the biased pawl when abutting a top of a first tooth of the toothed gear to have the abutting extremity hovering over a neighboring second tooth upon rotation of the toothed gear. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the biased pawl has a straight face opposed to the rounded back face. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the teeth have a top and a side, and wherein the control mechanism is operable according to at least three states based on if one of the rounded back face and the straight face is contacting one of the top and the side of one of the teeth. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the biasing means is a recoil spring. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the frame has a U-shaped structure having two arms with the tie down media being wound between the arms. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, further including a force-multiplying mechanism connected to the shaft. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the force-multiplying mechanism includes a first sprocket, a second sprocket and a chain linking the first sprocket and the second sprocket. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the first sprocket is rotatably mounted to the frame and the second sprocket is fixedly mounted to the shaft. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, further including a drum fixedly mounted to the shaft, wherein the tie down media is wound around the drum. 
     In some aspects, the techniques described herein relate to a self-retracting tie down winch, wherein the drum includes a hollow cylindrical wall defining a room therein with the biasing means mounted in the room 
     In some aspects, the techniques described herein relate to a vehicle including a cargo bed and a self-retracting tie down winch for securing a cargo on the cargo bet, including: a frame for mounting to the vehicle; a shaft rotatably mounted to the frame adapted to receive a tie down media to be used to secure the cargo, the tie down media being adapted to be wound around the shaft, and urging rotation along with the shaft when the tie down media is wound or unwound; a biasing means fixedly mounted to the shaft, the biasing means being anchored to the frame; wherein upon unwinding the tie down media, rotation of the shaft loads the biasing means, and wherein load accumulated in the biasing means helps rewind the tie down media around the shaft. 
     In some aspects, the techniques described herein relate to a vehicle, further including a control mechanism including a toothed gear including a first tooth-free portion separating two teethed portions and a biased pawl cooperating with the toothed gear. 
     In some aspects, the techniques described herein relate to a vehicle, wherein the biasing means is a recoil spring. 
     The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. Other and further aspects and advantages of the present invention will be obvious upon an understanding of the illustrative embodiments about to be described or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features and advantages of the invention will become more readily apparent from the following description, reference being made to the accompanying drawings in which: 
         FIG. 1  is showing a perspective rear view of a typical flat bed trailer with a self-retracting tie down winch according to a first embodiment installed; 
         FIG. 2  is showing a perspective view of an operator using the self-retracting tie down winch and binding tie down media to secure the cargo; 
         FIG. 3  is showing a front elevational view of an embodiment of the self-retracting tie down winch; 
         FIG. 4  is showing a front perspective view of the self-retracting tie down winch with the rewinding mechanism enclosure removed; 
         FIG. 5  is showing an exploded view of the self-retracting tie down winch; 
         FIG. 6  is showing a right elevational view of the locking mechanism in an unwinding state; 
         FIG. 7  is showing a right elevational view of the locking mechanism in a locked state; 
         FIG. 8  is showing a right elevational view of the locking mechanism in a free state; 
         FIG. 9  is showing a right elevational view of the locking mechanism in a rewinding state; 
         FIG. 10  is showing a perspective rear view of a typical flat bed trailer with the self-retracting winch apparatus installed in accordance with another embodiment; 
         FIG. 11  is showing a perspective view of an operator using the self-retracting tie down winch depicted on  FIG. 10  and binding tie down media to secure the cargo; 
         FIG. 12  is a sectional perspective view of the operator using the self-retracting tie down winch depicted on  FIG. 11 ; 
         FIG. 13  is a front elevation view of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 14  is a right-side elevation perspective view of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 15  is a left-side elevation perspective view of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 16  is a front view of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 17  is a right side view of the self-retracting tie down winch of  FIG. 11  with a portion of the frame removed; 
         FIG. 18  is a left side exploded perspective view of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 19  is a right side exploded perspective view of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 20  is showing a right elevational view of the locking mechanism in an unwinding state of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 21  is showing a right elevational view of the locking mechanism in a locked state of the self-retracting tie down winch of  FIG. 11 ; 
         FIG. 22  is showing a right elevational view of the locking mechanism in a free state of the self-retracting tie down winch of  FIG. 11 ; and 
         FIG. 23  is showing a right elevational view of the locking mechanism in a rewinding state of the self-retracting tie down winch of  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION 
     As a preliminary matter, it will be understood by one having ordinary skill in the relevant art (‘Ordinary Artisan’) that the invention has broad utility and application. Furthermore, any embodiment discussed and identified as being “preferred” is Considered to be part of a best mode contemplated for carrying out the invention. Other embodiments also may be discussed for additional illustrative purposes in providing a full and enabling disclosure of the invention. Furthermore, an embodiment of the invention may incorporate only one or a plurality of the aspects of the invention discloses herein; only one or a plurality of the features disclosed herein; or combination thereof. As such, many embodiments are implicitly disclosing herein and fall within the scope of what is regarded as the invention. 
     Accordingly, while the invention is described herein in detail in relation to one or more embodiments, it is to be understood that this disclosure is illustrative and exemplary of the invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The detailed disclosure herein of one or more embodiments is not intended, nor is to be construed, to limit the scope of patent protection afforded the invention in any claim of a patent issuing here from, which scope is to be defined by the claims and the equivalents thereof. II is not intended that the scope of patent protection afforded the invention be defined by reading into any claim a limitation found herein that does not explicitly appear in the claim itself. 
     Thus, for example, any sequence(s) and/or temporal order of steps of various processes or methods that are described herein are illustrative and not restrictive. Accordingly, it should be understood that, although steps of various processes or methods may be shown and described as being in a sequence or temporal order, the steps of any such processes or methods are not limited to being carried out in any particular sequence or order, absent an indication otherwise. Indeed, the steps in such processes or methods generally may be carried out in various different sequences and orders while still falling within the scope of the invention. Accordingly, it is intended that the scope of patent protection afforded the invention is to be defined by the issued claim(s) rather than the description set forth herein. 
     Additionally, it is important to note that each term used herein to that which the Ordinary Artisan would understand such term to mean bases on the contextual use of such term herein. To the extent that the meaning of a term used herein-as understood by the Ordinary Artisan based on the contextual use of such term-differs in any way from any particular dictionary definition of such term, it is intended that the meaning of the term as understood by the Ordinary Artisan should prevail. 
     With regard solely to construction of any claim with respect to the United States, no claim element is to be interpreted under 35 U.S.C. 112(f) unless the explicit phrase “means for” or “step for” is actually used in such claim element, whereupon this statutory Provision is intended to and should apply in the interpretation of such claim element. with regard to any method claim including a condition precedent step, such method requires the condition precedent to be met and the step to be performed at least once during performance of the claimed method. 
     Furthermore, it is important to note that, as used herein, “a” and “an” each generally denotes “at least one,” but does not exclude a plurality unless the contextual use dictates otherwise. Thus, reference to “a picnic basket having an apple” describes “a picnic basket having at least one apple” as well as “a picnic basket having apples.” In contrast, reference to “a picnic basket having a single apple” describes “a picnic basket having only one apple.” 
     When used herein to join a list of items, “or” denotes “at least one of the items,” but does not exclude a plurality of items of the list. Thus, reference to “a picnic basket having cheese or crackers” describes “a picnic basket having cheese without crackers.” “a picnic basket having crackers without cheese”, and “a picnic basket having both cheese and crackers.” When used herein to join a list of items, “and” denotes “all of the items of the list.” Thus, reference to “a picnic basket having cheese and crackers” describes “a picnic basket having cheese, wherein the picnic basket further has crackers,” as well as describes “a picnic basket having crackers, wherein the picnic basket further has cheese.”. 
     Referring the drawings, one or more preferred embodiments of the invention are next described. The following description of one or more preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its Implementations, or uses. Hence, a novel ribbed aerodynamic skirt in accordance with principles and embodiments of the present invention will be described herein after. 
     While illustrative and presently preferred embodiment(s) of the invention have been described in detail hereinabove, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior Art. 
       FIG. 1  and  FIG. 2  illustrate a typical transport vehicle  20 , equipped with the self-retracting tie down winch  40  (hereinafter SRTDW  40 ). The transport vehicle may be any kind of moving vehicle with a space for cargo with the need of a tie down system to secure a cargo. The hereby embodiment is represented on a flatbed trailer. 
     The SRTDW  40  are secured the left side frame  24  by welding, bolting or any other way known to those skilled in the art. It is important to note that the SRTDW  40  may be placed in either or both sides of the transport vehicle without departing from the scope of the invention. The SRTDW  40  may also be secured on rails (not shown) in order to be moved longitudinally along the left side frame  24  to allow a better placement of the tie down media  42  in order to effectively secure the cargo. 
     To understand prior art,  FIG. 3  is used for reference. In prior art, when the operator  30  needs to secure a cargo, the operator  30  has to move the binding pawl  48  away from the binding gear  50 , to pull the tie down media  42  sufficiently to reach the opposite side of the vehicle or attachment point. After, the operator  30  has to take up the slack from the tie down media  42  and then use a binding means represented here as a winch bar  34  to finally secure the cargo on the vehicle bed  28 . Once the cargo removed, the tie down media has to be either removed completely from the winch or rolled by hand. Both methods are time consuming even when removing media since it has to be stored in an orderly manner. 
     In the present invention, the operator  30  has to put the binding pawl  48  away from the binding gear  50 , pull the needed length of tie down media and find a locking state of the SRTDW  40 . The different states of the SRTDW  40  are explained in further details. Then, attach the end of the tie down media  42  to the determined point. Slightly pull on the tie down media  42  to engage in the rewinding state, this takes up the slack automatically on the tie down media and then, the operator  30  may proceed to secure the cargo on the vehicle bed  28  as done in prior art. Once the cargo untied and removed, with the binding pawl  48  away from the binding gear  50 , the operator  30  simply needs to guide the tie down media  42  in the winch since it&#39;s already in a rewinding state. 
       FIG. 3  illustrates one embodiment of the invention. Other embodiments such as, but not limited to, a right-side winding winch, different tie down medias or binding methods, are contemplated within the scope of the invention. The SRTDW  40  is assembled around a winch frame  44  having a U-shape comprising two arms extending downward from a central section. The winch frame  44  is secured through the central section to the bed of the transport vehicle  20  using known methods to those skilled in the art. On its left side, the winch driver  54 , used conjointly with a winch bar  34  ( FIG. 2 ), operates rotationally the winch shaft  58  when securing a cargo. The tie down media  42  is axially spooled around the winch shaft  58  having axis  52 , generating a pulling force between the transport vehicle  20 , the cargo  38  and the SRTDW  40 . The high tension generated is then maintained with the binding gear  50  that is affixed to the winch shaft  58  by the binding pawl  48  engaging in one of the tooth  56  of the binding gear  50 . 
     On the left side of the winch frame  44 , the rewinding mechanism  74  (not shown) is protected by a rewinding mechanism enclosure  90  preferably hermetically sealing the mechanism to protect it from particles, water and other contaminants encountered during transport. A completely enclosed mechanism ensures long term reliability. In this embodiment, at the end of the rewinding mechanism enclosure  90 , a gang connector  94  is welded. This gang connector  94  allows multiple SRTDW  40  to be connected and secured with a lock pin  98  when they are not in use. This feature is used when plural SRTDW  40  are affixed to a rail and there&#39;s a need to regroup the winches at the same place for further use. 
     Moving now to  FIG. 4  and  FIG. 5  showing the rewinding mechanism enclosure  90  have been removed in order to show the rewinding mechanism  74  of the embodiment and exploded view of the embodied tie down winch. One of the holder plates  64  of the mechanism is secured to the winch frame  44  using fasteners and spacers  62 . The second holder plate  64  is secured to the first one with fasteners  66  and spacers  68 . In the room defined in-between the spacers  68 , the recoil spring  60  (La, biasing means), in this embodiment, represented as a spiral spring, is operatively connected to the winch shaft  58  and its friction is reduced by the means of a pair of thrust bearings  70 . One thrust bearing  70  is affixed to the interior part of each holder plate  64 . Furthermore, the recoil spring  60  is also anchored, i.e., connected the one of the spacers  68  to retain the rotational force accumulated when the tie down media  42  is extracted, thus loading the recoil spring  60 . At the end of the mechanism, the spring  104 , pawl  110  and gear  100  which is axially connected to the winch shaft  58 , constituting the locking mechanism, aka control mechanism, of the rewinding mechanism  74 . 
     Visible on  FIG. 5 , the winch shaft  58  is supported by sealed bearings  130  inside bearing brace  80  and retained in place with a collar  108  (when needed) to reduce rotational friction. Also to reduce friction, a pair of guide plates  84  are used between the winch frame  44  and tie down media  42 . Another friction reducing component can be observed. Between the holder plates  64  and the recoil spring  60 , the spring thrust bearings  70  are affixed to the holder plate&#39;s interior sides. The sealing of the rewinding mechanism  74  is then completed by a gasket  92  or by any other means of sealing. 
       FIGS. 6, 7, 8 and 9  depict the plurality of states (4) of the locking mechanism. 
     Unwinding state. The first state depicted in  FIG. 6  is an unwinding state where the tie down media  42  (not shown) can be freely extracted by an operator to secure a cargo. In this embodiment and according to depiction, the unwinding state is in a clockwise rotation  114 ′. The extraction of the tie down media  42  induces a clockwise rotation  114 ′ to the winch shaft  58 . The gear  100 , axially connected to the winch shaft  58 , rotates about the winch shaft  58 . The abutting extremity  122  of the pawl  110  is lifted by the gear tooth in direction  118 ′ in a rotational movement around the pivot  120 . The spring  104 , connected to the opposed extremity  124  of the pawl  110 , keeps a bias on the pawl  110  towards the gear  100 . The extraction of the tie down media  42  in the unwinding state winds up the recoil spring  60  (not shown) so that the recoil spring  60  gains tension. 
     Locking state. In  FIG. 7 , upon release of the tie down media  42 , the recoil spring  60  releases tension and induces a counter-clockwise rotation  114 ″. If the abutting extremity  122  of the pawl  110  is within a toothed part of the gear  100 , as seen in  FIG. 7 , the rewinding mechanism  74  engages in a locking state wherein the tie down media  42  is prevented to retract in the winch. With a counter-clockwise rotation  114 ″, the spring  104  pulls the opposed extremity  124  of the pawl  110 , inducing the abutting extremity  122  of the pawl  110  to enter between teeth  102  and to move towards the deepest point of the gear. Therein, the rounded back face  128  of the pawl  110  abuts against the gear tooth  102  where it locks the winch shaft  58  against further counter-clockwise rotation  114 ″ while the slope of the straight portion  126  maintains a possible clockwise rotation  114 ′ of the winch shaft  58 . The locking state allows an operator to move the tie down media  42  to the desired position without being bothered by the retracting tension. The locking state also allows an operator to extract more tie down media  42  if needed. 
     When the end of the tie down media  42  is secured to, e.g., the other side of the vehicle bed, thus the cargo is ready to be secured, the locked state is not needed anymore. Before binding the media to secure the cargo, the apparatus needs to pass in the rewinding state. 
     Free state. In order to pass to the rewinding state, the locking mechanism needs to be in a free state depicted in  FIG. 8 , wherein the pawl  110 , the abutting extremity  122  in the toot-free part, allows either a clockwise rotation  114 ′ or a counter-clockwise rotation  114 ″. In this tooth-free part  142  of the gear tooth  102 , the spring  104  can pull the pawl  110  into a neutral position wherein the straight portion  126  is about parallel to a line joining the center of the winch shaft  58  and the center of the pivot  120  of the pawl  110 . If a clockwise rotation  114 ′ is induced, the straight portion  126  of the pawl  110  is rubbed against the first encountered teeth  102  of the gear  100  and following ones, hence entering an unwinding state (when rotating, e.g.,  FIG. 6 ) and a locking state (once stopped, e.g.  FIG. 7 ) in which the straight portion  126  of the pawl  110  is inserted between tooth  102  of the toothed portion  144  of the gear  100 . 
     Rewinding state. If a counter-clockwise rotation  114 ″ is induced from the free state depicted on  FIG. 8 , the mechanism is engaged in a rewinding state as depicted in  FIG. 9 . The pawl  110  rotates in direction  118 ″ around the pivot  120 . The spring  104  biases the rounded back face  128  of the pawl  110  towards the gear  100 . The round back face  128  of the pawl  110  slides over the tooth  102 . This allows the tension accumulated in the recoil spring  60  to be released, spooling the tie down media  42  onto the winch shaft  58 . 
     It should be noted that the radius of curvature of the rounded back face  128  of the pawl  110  is adapted to allow the rounded back face  128  to slide over the teeth  102  in either rotation direction  114 ′ and  114 ″, allowing a direction change. 
     The tie down media  42  comprises a mean for the tie down media  42  to remain secured to the winch in case the tie down media  42  is completely unwound from the winch shaft  58 . In this embodiment a hook &amp; loop strap also known as a Velcro™ is sewn at the end of the webbing. The hook &amp; loop strap is inserted through a slot of the winch shaft  58 , moved around the winch shaft  58  and then pressed to the corresponding portion on the webbing. The flat portion of the webbing is then sewn on itself, leaving a loop at the extremity. The webbing is inserted through the slot of the winch shaft  58 . A lock pin (not shown) is inserted in the webbing loop to secure the tie down media to the winch shaft  58 . 
     In this embodiment the tie down media  42  is fastened to the winch shaft using permanent or removable fasteners. 
     Referring now to  FIGS. 10 to 23 , another embodiment of a SRTDW  41  differ from the SRTDW  40  of  FIGS. 3 to 9  in the SRTDW  41  comprising a drum  106  mounted to the winch shaft  58  to wind up the tie down media  42  around a larger cylindrical surface. The larger cylindrical surface, typically of a diameter of about 6½ inches, allows more rigid tie down media  42 , e.g., steel cables, which would not wound easily around a small cylindrical surface. The larder cylindrical surface further provides a smaller ratio of number of rotations per linear unit, thus less rotations to rewind the tie down media  42  once untied from the vehicle bed. The drum  106  further provides a room therein to place the recoil spring  60  therein. Accordingly, a greater portion of the mechanism of the SRTDW  41  is located between the arms of the winch frame  44 , with the winch frame  44  and the drum  106  protecting the recoil spring  60  from weather and particles. 
     The SRTDW  41  further features a force-multiplying mechanism  132 . The force-multiplying mechanism  132  comprises a first sprocket  134  driven by the winch driver  54 . The first sprocket  134  is connected to a second sprocket  136  with a chain  138 . The second sprocket  136  has a greater number of teeth than the first sprocket  134 , decreasing the force required to drive the winch driver  54  compared to direct driving based on the teeth ratio of the sprockets  134 ,  136 . The second sprocket  136  is rigidly connected to the winch shaft  58 , thereby transmitting power to the winch shaft  58  like if the winch driver  54  was connected to the winch shaft  58 . Accordingly, the operator has less efforts to exert to both bind the tie down media  42  and to change the state of the SRTDW  41  from, e.g., the locking state to the free state. 
     Another feature of the SRTDW  41  is the design of the gear  100  comprising two opposed toothed parts comprising each, e.g., three (3) teeth  102 , separated with two tooth-free parts, easing the task of entering the SRTDW  41  in the free state (e.g.,  FIG. 8 ) without affecting the robustness of the SRTDW  41  to stay and resist to forces induced by the tie down media  42  and the recoil spring  60  in the locking state (e.g.,  FIG. 7 ). 
     While preferred embodiments have been described above and illustrated in the accompanying drawings, it will be evident to those skilled in the art that modifications may be made without departing from this disclosure. Such modifications are considered as possible variants comprised in the scope of the disclosure.