Abstract:
The present invention includes an improved cargo restraint apparatus ( 10 ). The cargo restraint apparatus ( 10 ) comprises a pallet ( 20 ), a reel ( 30 ) having a locking mechanism, and a lock release ( 43, 143, 243 ) having a pressure plate ( 44, 144, 244 ) and a release shaft ( 45, 145, 245 ) having a rotation restricting widthwise cross-section. A force is applied to the pressure plate ( 44, 144, 244 ) to unlock the reel ( 30 ). The pressure plate ( 44, 144, 244 ) allows a user to release the restraints quickly and easily by kicking the pressure plate while keeping the user&#39;s hands free.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   None 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   None 
   BACKGROUND OF THE INVENTION 
   (1) Field of the Invention 
   The present invention relates generally to cargo restraint devices and more particularly to cargo restraint devices using a pawl and ratchet tensioning systems with a belt or strap to secure the cargo to a pallet. 
   (2) Description of the Related Art 
   A wide array of cargos are transported each day upon pallets which require restraint devices to securely hold them upon the transport vehicle during transit. Cargo restraint devices typically utilize pawl and ratchet locking mechanisms to keep a strap tight over the cargo. The cargo loaded pallets are stacked on top of one another upon the vehicle, so that the weight of the cargo causes the restraint straps of the lower pallets to loosen and the pawl and ratchet to lock the strap in a more retracted position than originally set by the operator. When the weight of the cargo pallets stacked above are removed at the destination, the straps become exceedingly tight, which wedges the pawl against the teeth of the ratchet under such a pressure so as to make it difficult to disengage the pawl and release the strap. This forces operators to use their hands to release heavy cargos in an unsafe manner. While related cargo restraint devices utilize straps locked by pawl and ratchet systems, there are no hands-free devices which can be easily kicked to force a pawl to disengage from a ratchet to allow a safe and quick release of restraint straps from cargo on a pallet. 
   U.S. Pat. No. 2,775,463 to Chenette discloses an appliance hand truck having an endless belt track for easy transport up a stairway. The appliance hand truck has a tensioning means for a restraining strap to hold the appliance securely on the truck. The strap tensioning means uses a pawl to prevent the reverse rotation of the ratchet wheel when a strap is under tension. To release the tensions upon the strap, the pawl 44 is disengaged from the ratchet wheel by pulling an end of the pawl to disengage it from the ratchet wheel. 
   U.S. Pat. No. 3,175,806 to Prete, Jr discloses a ratchet type buckle for tensioning an elongated flexible member such as a strap, rope or cable. The ratchet type buckle has a driving pawl for engaging ratchet teeth. The inner end of the driving pawl is formed with two pawl fingers that straddle the spool for the purpose of engaging the ratchet teeth to drive the spool in the direction to wind in the strap. When the spool is to be released for reverse rotation to release the strap, the handle 64 manually retracts the driving pawl and the pawl is held in the retracted position to prevent further engagement with the ratchet teeth. 
   U.S. Pat. No. 3,804,368 to Bailey discloses a ratchet tensioner comprising a reciprocal lever mounting a first pawl engaging a ratchet wheel connected to two parallel bars forming a reel. When the lever moves in the opposite direction, the first pawl rides over the ratchet wheel and a second pawl engages the ratchet wheel to prevent unwinding of webbing from the reel. The pawls are lifted out of engagement with the ratchet wheel to allow the reel to freely rotate by manually pulling the release member 37. 
   U.S. Pat. No. 5,101,537 to Cummings discloses a ratchet tie down structure that is designed to hold heavy objects in place on a transport vehicle. The mechanism includes a base element attached to the transport vehicle that has pair of cooperating elements having interfitting ratchet teeth and a latch that permits a shaft to be turned in one direction to tighten a flexible holding element attached to the object. The ratchet teeth can be disengaged by fitting the plain end of a bar into one of the sockets of the latch and pushing the latch inwardly against the bias of the spring to disengage the ratchet teeth of the two elements. 
   U.S. Pat. Nos. 5,145,299 and 5,186,586 to Stephenson, Jr. disclose a remote release mechanism which permits restraints such as flat straps placed around a load and placed in tension by a winch to be released by an operator positioned on the same side of the transportation structure as the winch. This permits the hook end of a load restraint to be released from the winch side of the transportation structure, eliminating the need to perform separate operations on either side of the restraint mechanism. The apparatus comprises a hook bar connected to a rotatable drum which is held from rotation in one direction by a pawl 112 and ratchet. The pawl is released by the pulling a remote release rod to swing the pawl from the teeth of the ratchet. 
   U.S. Pat. No. 5,490,749 to Arbues discloses a winch for securing the tie down straps used to restrain cargo transported on a flatbed vehicle. The winch includes a rigid frame having a rotatable winch drum on which the strap may be wound. A ratchet wheel on the end of the winch drum includes two sets of teeth which are axially offset and circumferentially staggered relative to each other. A pawl for locking the ratchet wheel has two similarly offset and staggered sets of teeth. The teeth of the pawl and ratchet wheel interlock at locations that are both axially and circumferentially offset to distribute the stresses and enhance the structural strength of the winch. The end of the pawl presents a tip 54 which may be gripped with the fingers to release the pawl from the ratchet teeth. 
   U.S. Pat. No. 5,549,429 to Sergent discloses a tool 30 for manipulating a ratcheted strap-tightening mechanism such as those associated with cargo securing harnesses. The tool comprises a handle having at a first end a socket adapted to engage the lever of the ratcheting mechanism, and a tongue adapted to unlock the ratcheting mechanism at the other end. The tongue is shaped and dimensioned to be inserted between the locking pawl and the drum to pry the pawl away from the teeth of the ratcheting mechanism. 
   U.S. Pat. No. 5,943,742 to Huang discloses a strap tightening/loosening device having two side plates with a connecting plate, a handle mounted to the side plates with a shaft extending through the handle and the side plates, and two ratchets mounted to the shaft. Each of the two side plates have two slots and an elongated slot, two members slide and are received within the two slots so that one of the members is engaged with the ratchets. The first member has two first pawls which engage the ratchets, while a second member also has two second pawls. The pawls are lifted from the ratchet by cam means when the handle is extended. 
   U.S. Pat. No. 6,059,499 to Bird discloses a retractable cargo securement strap assembly. A threaded post and a pair of clamps allow for removably mounting the housing of the strap assembly to a vehicle. A spool assembly situated within the housing makes it possible to retract the strap within the housing. The strap assembly has a locking assembly comprising a pivoting pawl which engages the teeth of a ratchet wheel. The pawl is disengaged from the ratchet wheel teeth by pushing a push button lever lifts an elongated arm which lifts the pawl from the teeth of the ratchet wheel. 
   U.S. Pat. No. 6,141,840 to Berkes discloses a buckle for releasably engaging a tongue of a cargo restraint system. The tongue is released from the buckle by lifting a lever to disengage the tongue. Berkes does not disclose a pawl and ratchet locking system with a lock release for the cargo restraint system. 
   U.S. Patent Application Publication No. 2003/0031524 to Brunet discloses a strap winch device assembly for fitting on a flat bed open truck trailer, to enable a truck driver to remotely activate the system without leaving the truck cab. The winch devices are connected along the side of the trailer to a single fore and aft drive shaft driven by a motor to tighten any straps that loosen during transit. A cable is connected at one end to a slider plate adjacent to biasing springs and at the other end to a clutch release handle member. Pulling upon the handle member pulls the cable, which moves the slider plate against the coil springs. The pulling force of the cable moves the shaft away from the drive shaft so that the teeth of the gears no longer are intermeshed. 
   U.S. Patent Application Publication No. 2003/0084550 to Fang discloses a strip safe-releasing device using a pawl and ratchet. A pawl engages the teeth of the ratchet to maintain the tension on the strip. The strip tension can be released by extending the handle so that the convex portion of the handle lifts the pawl from the teeth of the ratchet. 
   While the related art teach cargo restraint devices, there still exists a need for improved cargo restraints which have simple release mechanisms that do not require use of the hands. 
   OBJECTS 
   Therefore, it is an object of the present invention to provide an improved cargo restraint apparatus. 
   It is further an object of the present invention to provide a method of using an improved cargo restraint apparatus. 
   These and other objects will become increasingly apparent by reference to the following description. 
   SUMMARY OF THE INVENTION 
   The present invention provides a cargo restraint apparatus comprising a pallet with a mounting surface, a reel comprising a housing affixed to the mounting surface of the pallet, a spool rotatably mounted upon an axle attached to the housing, a ratchet wheel having a plurality of teeth coaxially linked to the spool, and a pawl pivotally mounted within the housing which removably engages the teeth of the ratchet with a pawl blade, thereby forming a reel locking mechanism, a strap retractably wound around the spool of the reel, so that the strap can be unwound from the spool to wrap over the cargo whereupon release of the tension and retraction of the strap locks the pawl blade into the teeth of the ratchet thereby locking the spool in place and preventing further extension of the strap to securely hold the cargo to the pallet, and a lock release comprising a pressure plate and a release shaft having a rotation restricting widthwise cross-section slidably mounted upon the pallet adjacent to the reel, projecting from the pressure plate and extending towards the pawl, whereby upon application of a force to the pressure plate the force is transmitted to strike and pivot the pawl thereby removing the pawl blade from the teeth of the ratchet to allow the spool to turn and the strap to extend, thereby releasing the tension holding the cargo to the pallet. 
   In further embodiments of the cargo restraint apparatus the lock release further comprises at least one retainer attached to the release shaft which keeps the lock release from separating from the pallet. In further still embodiments of the cargo restraint apparatus the retainer is selected from the group consisting of pins, clips, and fins. In further still embodiments of the cargo restraint apparatus the lock release further comprises a spring which maintains the release shaft in a retracted position away from the pawl until the force is applied to the pressure plate. In further still embodiments of the cargo restraint apparatus the release shaft further comprises one or more stops which keep the release shaft from extending too far inwardly when the force is applied to the pressure plate. In further still embodiments of the cargo restraint apparatus the lock release further comprises one or more stabilizer shafts which stabilize the lock release when the force is applied to the pressure plate off center. In further embodiments of the cargo restraint apparatus the lock release is mounted within a recess in a side of the pallet. In further still embodiments of the cargo restraint apparatus the pressure plate extends from the recess such that it can be kicked by a user to release the cargo when the pallet is in a position to be unloaded. 
   The present invention further provides a method of using a cargo restraint apparatus comprising providing the cargo restraint apparatus comprising a pallet with a mounting surface, a reel comprising a housing affixed to the mounting surface of the pallet, a spool rotatably mounted upon an axle attached to the housing, a ratchet wheel having a plurality of teeth coaxially linked to the spool, and a pawl pivotally mounted within the housing which removably engages the teeth of the ratchet with a pawl blade, thereby forming a reel locking mechanism, a strap retractably wound around the spool of the reel, so that the strap can be unwound from the spool to wrap over the cargo whereupon release of the tension and retraction of the strap locks the pawl blade into the teeth of the ratchet thereby locking the spool in place and preventing further extension of the strap to securely hold the cargo to the pallet, and a lock release comprising a pressure plate and a release shaft having a rotation restricting widthwise cross-section slidably mounted upon the pallet adjacent to the reel, projecting from the pressure plate and extending towards the pawl; positioning the cargo upon the pallet; extending the strap around the cargo; retracting the strap to secure the cargo upon the pallet whereby the pawl blade pivots into the teeth of the ratchet to lock the spool of the reel; and applying a force to the pressure plate of the lock release which transmits the force to strike and pivot the pawl which disengages the pawl blade from the teeth of the ratchet, allowing the reel to freely rotate and the strap upon the reel to extend and release the cargo from the pallet. In further embodiments of the method the force to the pressure plate is applied by a user kicking the pressure plate to release the cargo from the pallet. 
   The present invention further provides a cargo restraint apparatus of the type with a reel having a pawl, ratchet and strap fastened to a pallet which holds cargo to the pallet during shipping, wherein the improvement comprises a pressure plate attached to a release shaft having a rotation restricting widthwise cross-section slidably mounted upon the pallet, whereupon application of a force to the pressure plate the force is transmitted to strike and pivot the pawl thereby removing the pawl from the teeth of the ratchet to allow the strap to extend, thereby releasing tension holding the cargo to the pallet. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of an embodiment of a cargo restraint apparatus of the present invention showing the lock release mounted on the pallet. 
       FIG. 2  is a cross-sectional view of the reel and lock release of the present invention taken along line  2 — 2  in  FIG. 1 . 
       FIG. 3  is perspective view of an embodiment of the reel, belt and lock release of the present invention. 
       FIG. 4  is top view of an embodiment of the reel, belt and lock release of the present invention. 
       FIG. 5  is a top view of an embodiment of a lock release of the present invention. 
       FIG. 6  is side view of an embodiment of a lock release of the present invention. 
       FIG. 7  is front view of an embodiment of a lock release of the present invention showing the pressure plate. 
       FIG. 8  is side view of a further embodiment of a lock release having shoulders. 
       FIG. 9  is top view of a still further embodiment of a lock release having stabilizer shafts. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   All patents, patent applications, government publications, government regulations, and literature references cited in this specification are hereby incorporated herein by reference in their entirety. In case of conflict, the present description, including definitions, will control. 
   One embodiment of the present invention of a cargo restraint apparatus  10  is illustrated in  FIGS. 1–7  having a pallet  20  upon which the cargo is placed for shipping. The pallet  20  can be of any configuration known in the art. An embodiment is illustrated in  FIG. 1 , which has a top face  23 , an opposing bottom face (not shown), and one or more sides  24 . As illustrated in  FIGS. 1 and 2 , within the one or more sides  24  is a recess  21  defined by a back wall  70 , a first side wall  74 , a second side wall  76 , a bottom wall  72 , and a top wall  78  which is affixed beneath the top face  23  of the pallet  20 . As illustrated in cross-section in  FIG. 2 , a reel  30  is attached behind the back wall  70  of the recess  21  to a mounting surface  22  continuous with the top wall  78  which is affixed beneath the top face  23  of the pallet  20 . The reel  30  is secured to the mounting surface  22  by a bolt  60  or any other securing means known to a person skilled in the art. The reel  30  is enclosed within in a debris cover  62  to protect the reel from grit which might interfere with the workings of the reel  30 . While  FIG. 2  illustrates the reel  30  mounted in a preferred configuration, it is to be understood that any placement of the reel  30  which will allow it be accessed to tie down the cargo against the face of the pallet  20  is encompassed by the present invention. 
   As illustrated in  FIGS. 3 and 4 , the reel  30  comprises a housing  31  which is affixed to the mounting surface  22  of the pallet  20  and a spool  32  rotatably mounted upon an axle  33  attached to the housing  31 . The spool  32  rotation is resisted in one direction by a spool spring  32 A which maintains a tension upon a strap  42  having a distal end  42 A with an attached tongue  42 B for a mating belt buckle (not shown) on the pallet lid, and a proximal end (not shown) attached and wound upon the spool  32 . A reel locking mechanism is comprised of a first ratchet wheel  34  and second ratchet wheel  35  each having a plurality of teeth  36 , which are coaxially linked to the spool  32 , a pawl  37 , a pawl spring  37 A, pawl lifter  37 C and pawl lifter spring  37 D. 
   The pawl  37  having a first pawl blade  39  and a second pawl blade  41  is pivotably mounted within the housing near the outer radius of the first ratchet wheel  34  and the second ratchet wheel  35 . The pawl is mounted forward of the spool  32  towards the back wall  70  of the recess  21  in the side  24  of the pallet  20 . The pawl  37  is forced against the first ratchet wheel  34  and the second ratchet wheel  35  by the pawl spring  37 A attached to the pawl  37  having a runner  37 B at a first end and anchored to the housing  31  at an opposing second end to hold the first pawl blade  39  and second pawl blade  41  down onto the first ratchet wheel  34  and the second ratchet wheel  35 , respectively. The pawl lifter  37 C has a flat tooth  37 E and a rounded tooth  37 F each of which have a larger radius than the first ratchet wheel  34  The pawl lifter  37 C is coaxially mounted upon the axle  33  with the spool  32  adjacent to the first ratchet wheel  34  where it is held against the first ratchet wheel  34  by the pawl lifter spring  37 D mounted between the pawl lifter  37 C and the housing  31 . 
   When the strap  42  is fully retracted, the strap near the distal end  42 A lifts upon the runner  37 B of the pawl spring  37 A, holding the pawl  37  high enough from the ratchet wheel  34   35  so that the flat tooth  37 E of the pawl lifter  37 C can slip beneath the first pawl blade  39 . Extending the strap rotates the spool  32 , whereupon the friction upon the pawl lifter  37 C causes it to rotate with the spool  32  and move the flat tooth  37 E of the pawl lifter  37 C beneath the first pawl blade  39  so as to hold the pawl  37  in a disengaged position above the first ratchet wheel  34  and second ratchet wheel  35  until tension is released from the strap  42  to allow retraction of the strap  42 . When the strap  42  retracts, the flat tooth  37 E of the pawl lifter  37 C rotates out from beneath the first pawl blade  39  so that the pawl  37  is free to rotate to engage the first ratchet wheel  34  and the second ratchet wheel  35 , making further extension of the strap  42  impossible but allowing retraction. 
   Retraction is possible to further tighten the belt  42  to secure the cargo. The pawl  37  is lifted wherever further retraction is attempted by the rounded tooth  37 F of the pawl lifter  37 C whenever the spool rotates in the retracting direction. The pawl  37  removably engages the teeth  36  of the first ratchet wheel  34  and second ratchet wheel  35  with a first pawl blade  39  and second pawl blade  41 , respectively. The strap  42  is retractably wound around the spool  32  of the reel  30 , so that the strap  42  can be unwound from the spool  32  to wrap over the cargo whereupon release of the tension and retraction of the strap  42  locks the first pawl blade  39  and second pawl blade  41  into the teeth of the first ratchet wheel  34  and second ratchet wheel  35  to lock the spool  32  securely in place and preventing further rotation of the spool  32  and extension of the strap  42  thereby securely holding the cargo to the pallet  20 . 
     FIGS. 5–7  illustrate one embodiment of a lock release  43  comprising a pressure plate  44  and a release shaft  45  having a rectangular widthwise cross-section which is slidably mounted within a rectangular release shaft orifice  79  penetrating the back wall  70  within the recess  21  of the pallet  20  adjacent to the reel  30 . While  FIG. 2  illustrates one embodiment of the release shaft orifice  79 , it is to be understood that the support can be contiguous with the reel housing, or can exist as a separately mounted apparatus. The release shaft  45  projects from the pressure plate  44  and extends towards the pawl  37  through release shaft orifice  79 . Since the pawl  37  is situated forward of the spool  32 , the release shaft  45  can directly contact the pawl  37  when the pressure plate  44  is pressed inward. The rectangular widthwise cross-section of the release shaft  45  fits within the rectangular release shaft orifice  79  in such a manner that the release shaft  45  is restricted rotationally around the lengthwise axis of the release shaft  45 . In other embodiments of the lock release  43 , the release shaft  45  and release shaft orifice  79  have any shape which will restrict rotation of the release shaft  45 , including but not limited to triangular, rectangular, pentagonal, hexagonal, star-shaped polygon or any other polygonal shape. A lock release spring  46  encircling the release shaft  45  and resting towards the first end  45 A of the release shaft  45  upon the back wall  70  and at the second end  45 B of the release shaft  45  against the pressure plate  44  holds the release shaft  45  in a retracted position away from the pawl  37  until a force is applied to the pressure plate  44 . The lock release  43  has a retainer at the first end  45 A of the release shaft  45  comprised of a first retainer fin  81 A and a second retainer fin  81 B which together extend wider than the release shaft orifice  79 , thereby keeping the release shaft  45  from pulling out of the release shaft orifice  79  and separating from the pallet  20 . While the retainer illustrated in  FIG. 8  is comprised of fins, it is to be understood that any retainers known in the art which are capable of holding the lock release  43  in place on the pallet  20  can be used. 
     FIG. 8  illustrates a further embodiment of a lock release  143  comprising a pressure plate  144  and a rectangular release shaft  145  having a first end  145 A and an opposed second end affixed to the pressure plate  144 . The release shaft has first shoulder  150  towards the second end  145 B and a second shoulder  160  of smaller cross-sectional area extending coaxially from the first shoulder towards first end  145 A of the release shaft  145 . The rectangular release shaft  145  is slidably mounted within the rectangular release shaft orifice  79  penetrating the back wall  70  within the recess  21  of the pallet  20 . The second shoulder acts as a stop to keep the release shaft  145  from extending farther than necessary to disengage the pawl  37 . A hole  180  penetrating the release shaft  145  towards a first end  145 A holds a retainer  181  which keeps the pressure plate  144  and release shaft  145  from separating from the pallet  20 . While the retainer  181  illustrated in  FIG. 8  is a pin, it is to be understood that any fastener known in the art, including but not limited to a cotter pin or a clip, which is capable of holding the lock release  143  in place can be used as a retainer. Further embodiments of the release shaft  145  have two or more holes for holding the retainer  181  in place. 
     FIG. 9  illustrates a still further embodiment of a lock release  243  comprising a pressure plate  244  having a front face  244 A and opposed back face  244 B, a first edge  244 C and an opposed second edge  244 D, and a rectangular release shaft  245  having a first end  245 A and an opposed second end attached to the back face  244 B of the pressure plate  244 . A first stabilizer shaft  260  having a shoulder portion  262  attached to the back face  244 B of the pressure plate  244  towards the first edge  244 C, and a narrow portion  264  which extends coaxially from the shoulder portion  262  to penetrate the back wall  70  of the recess  21 . Likewise a second stabilizer shaft  270  having a shoulder portion  272  attached to the back face  244 B of the pressure plate  244  towards the second edge  244 D, and a narrow portion  264  which extends coaxially from the shoulder portion  272  to penetrate the back wall  70  of the recess  21 . The first stabilizer shaft  260  and the second stabilizer shaft  270  thereby further support the pressure plate against twisting forces when a force is applied off center. Additionally, the shoulder portion  262  and shoulder portion  272  together act as a stop to keep the lock release  243  from extending too far inwardly. A hole  180  penetrating the release shaft  145  towards the first end  245 A holds a retainer (not shown) which keeps the pressure plate  144  and release shaft  145  from separating from the pallet  20 . 
   Upon application of the force, particularly by kicking with the foot, to the pressure plate  44  the force is transmitted to strike and pivot the pawl  37  thereby removing the first pawl blade  39  and the second pawl blade  41  from the teeth  36  of the first ratchet wheel  34  and the second ratchet wheel  35 , respectively, to allow the spool  32  to turn and the strap  42  to extend, thereby releasing the tension holding the cargo to the pallet  20 . 
   While the present invention is described herein with reference to illustrated embodiments, it should be understood that the invention is not limited hereto. Those having ordinary skill in the art and access to the teachings herein will recognize additional modifications and embodiments within the scope thereof. Therefore, the present invention is limited only by the claims attached herein.