Patent Publication Number: US-2007116536-A1

Title: Method and apparatus for converting cargo rings into six degree of restraint attachments

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      The present provisional application claims reference to U.S. Provisional Application No. 60/736,008, filed on Nov. 10, 2005, the entire contents thereof is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Technical Field  
      The present invention relates generally to clamps, and more specifically, to a method and apparatus for affixing cargo and/or equipment onto the surface/floor of a conveyance that utilizes standard cargo rings.  
      2. Description of Related Art  
      Many modern cargo conveyances, i.e. any means of providing transportation of or for cargo, use cargo rings as a securement or attachment point to secure/attach cargo to a surface of the conveyance to prevent it from shifting or moving. As illustrated in  FIG. 1 , the current art approach to securing the cargo is to use a variety of chains, ropes, and/or straps with a variety of pre-tensioning devices, including binders, tensioners, screws, slip-knots, or the like, to firmly secure the cargo in place using cargo rings, or other securement point means such as eye-bolts or the like. An example of a current art cargo ring is shown in  FIG. 2 . As shown, current art cargo ring  12  is attached to load securement surface  14 . The current art approach of installing temporary equipment in/on vehicles is similar.  
      Thus, current art methods are typically “tension only” devices; i.e., they only function to restrain using tension because, while a securement point of the current art may be rigid in one axis, i.e. the upward or Z-axis, they are generally flexible or mobile in the other axes.  
      Because of the flexibility inherent in multiple axes in securement points of the current art, tension only devices of the current art are limited in that the devices only restrain a portion of the load at any given time. For example, consider a large pallet of cargo mounted onto a flat bed truck. Best practice dictates that the pallet should have a minimum of four attachments, one from each corner of the pallet to the bed of the truck. For maximum effectiveness, the four attachments (ropes, straps, or chains) are typically angled away from the centerline of the truck bed.  
      In a static condition, i.e. no movement of the conveyance upon which the pallet is secured, tension only devices are adequate. But in a dynamic condition, i.e. movement of the conveyance, the limitations of the current art allow movement of the pallet. If the truck stops suddenly during braking, the pallet&#39;s momentum will tend to cause the pallet to slide forward. This forward momentum or movement will only be restrained by the two attachments behind/aft of the pallet. The two attachments forward of the pallet are ineffective to provide any counteracting force.  
      Continuing with the current example, if the truck accelerates, the pallet&#39;s momentum will tend to slide backward and only the two attachments forward of the pallet would be effective. A similar effect is noted for lateral forces. For example, to restrain a 5,000 pound equipment pallet in an aircraft with 5,000 pound capacity cargo rings, it would be necessary to use a minimum of four (4) cargo rings, one forward, one aft and one on each side because only one ring at a time would be effective. This is not an effective approach because it uses only one-fourth of the capacity of the cargo rings.  
      Current art techniques for attaching cargo/equipment to a cargo ring are, thus, limited to the number of securement points that will be effective in any given situation, because cargo rings react to tension loads only. This also results in the need to use a large number of securement points. What is needed is a method and apparatus that overcomes the limitations of the prior art; namely, a method and apparatus for restraint of a cargo or load in all possible axes of movement.  
     BRIEF SUMMARY OF THE INVENTION  
      Briefly described, in a preferred embodiment, the present invention overcomes the above-mentioned limitations and meets the recognized need by providing a method and apparatus that facilitates the reaction to tension loads in all directions, as well as torsion (twisting) loads about any axis.  
      In a preferred embodiment, the present invention comprises an adapter plate and a clamp. Generally, a load is attached to the adapter plate which is secured to the clamp of the present invention. The adapter plate has a slot that is sized appropriately to receive a cargo ring therethrough and retained against a structure by the clamp operably engaged with the cargo ring. The adapter plate of the present invention also has a seating surface that is frictionally engaged with the conveyance surface when the clamp of the present invention is secured to a securement point.  
      Further, pins in the adapter plate interface with matching holes in the base of the clamp to prevent any lateral motion between the adapter plate and the clamp. Adjusting a thumbscrew activates a lower locking mechanism, in the nature of a “lower jaw”, which locks the cargo ring into the assembly. A securing nut on the thumbscrew secures the present invention and prevents loosening of the clamp due to vibration. Once installed and adjusted, the present invention can resist forces between the adapter plate and the cargo ring in any direction. Torsional loads (moment loads) and other forces are transferred, at least in part, by the adapter plate into the structure.  
      The adapter plate can be adapted to attach to almost any cargo system or equipment configuration. Minor dimensional changes make the clamp assembly compatible with any existing ring configuration.  
      One of the more unique aspects of the clamp assembly is that it requires no modification to the original structure; it may be installed and removed without the need for any hand tools.  
      The invention described herein differs from the prior art in that it converts the cargo ring into a rigid attachment means that will react against tension and compression loads in all directions, as well as torsional (twisting) loads, about any axis. It accomplishes this action by pre-tensioning the “ring to floor” attachment against an adapter plate that the ring passes through. The adapter plate then provides the securement or attachment point for any desired cargo or equipment.  
      In one aspect of the present invention, a system is disclosed having a least one clamp adapted to releasably attach to a securement point, at least one adapter plate having a seating surface, and a load securement surface, wherein the adapter plate is removably attachable to the clamp.  
      In another aspect of the present invention, a method of securing a load to a securement point is disclosed, the method having the steps of removably attaching an adapter plate to a clamp and attaching the load to the adapter plate to secure the load to the securement point.  
      In a further aspect of the present invention, a clamp is described having a jaw with 1) a workpiece contacting end, 2) a central fulcrum 3) a cantilever element, and 4) at least one adapter plate removably attached to the clamp.  
      In a still further aspect of the present invention, a method is disclosed for converting a flexible securement point having sufficient structural capacity to provide a resistive force in or about a first axis, to a rigid securement point, having the step of converting a force in or about a second axis to a force in or about the first axis.  
      Accordingly, a feature and advantage of the present invention is its ability to provide a removable rigid securement point for rigidly securing a load.  
      Another feature and advantage of the present invention is its ability to provide a securement point capable of resisting motion in or about a plurality of axes.  
      Another feature and advantage of the present invention is its ability to resist motion in and about three mutually orthogonal axes.  
      Another feature and advantage of the present invention is its ability to provide a rigid securement point by converting an existing flexible securement point.  
      Another feature and advantage of the present invention is its ability to be removed, thereby re-converting the existing securement point to a flexible securement point.  
      Another feature and advantage of the present invention is its ability to be used with an existing securement point without permanent alteration thereof.  
      Another feature and advantage of the present invention is its ability to be attached to an existing securement point without tools.  
      These and other objects, features, and advantages of the invention will become more apparent to those ordinarily skilled in the art after reading the following Detailed Description of the Invention and Claims in light of the accompanying Figures.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      Accordingly, the present invention will be understood best through consideration of, and reference to, the following Figures, viewed in conjunction with the Detailed Description of the Invention referring thereto, in which like reference numbers throughout the various Figures designate like structure and in which:  
       FIG. 1  is a perspective view illustrating prior-art tension devices;  
       FIG. 2  is a perspective view of a typical cargo ring used to provide a point of securement;  
       FIG. 3  is a perspective view of the preferred embodiment of the clamp of the present invention;  
       FIG. 4  is an exploded view of the clamp of  FIG. 3 , illustrating the preferred components and assembly;  
       FIG. 5  is a plan view illustrating the clamp of  FIG. 3  in use with the cargo ring of  FIG. 2 ;  
       FIG. 6  is a side view illustrating the clamp of  FIG. 3  in use with the cargo ring of  FIG. 2 ;  
       FIG. 7  is a top perspective, exploded view illustrating the preferred method of securing the clamp of  FIG. 3  to an adapter plate of the present invention, the adapter plate providing a securement point for the load;  
       FIG. 8  is a bottom perspective, exploded view illustrating the preferred method of securing the clamp of  FIG. 3  to an adapter plate of the present invention, the adapter plate providing a securement point for the load;  
       FIG. 9  is a side view of the apparatus of  FIGS. 6 and 7 ;  
       FIG. 10  is a rear view of the apparatus of  FIGS. 6 and 7 ;  
       FIG. 11  is an elevated, perspective, cutaway view showing an alternative embodiment of the adapter plate;  
       FIG. 12  is a perspective, cutaway view showing the underside of the alternative embodiment of  FIG. 11 ;  
       FIG. 13  is a top view showing another alternative embodiment of the adapter plate of the present invention;  
       FIG. 14  is a side, cutaway view of the embodiment of  FIG. 13 ; and,  
       FIG. 15  is an elevated, perspective view of the embodiment of  FIG. 13 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      In describing preferred embodiments of the present invention illustrated in the Figures, specific terminology is employed for the sake of clarity. The invention, however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.  
      In that form of the preferred embodiment of the present invention chosen for purposes of illustration,  FIG. 3  shows clamp  40  preferably adapted to secure a load to the cargo ring of  FIG. 2 , which may be provided in a means of conveyance for a load. Clamp  40  preferably includes jaw  50  with workpiece end  50   a , central fulcrum  50   b , and cantilever element  50   c . More specifically, clamp  40  preferably includes workpiece contacting end  48  comprising workpiece contacting surface  48   a , for receiving a structure of a securement point, such as cargo ring  110  of  FIG. 2 . Workpiece contacting end  48  preferably further includes jaw  50  for securing the structure of the securement point, such as when the structure is in contact with workpiece contacting surface  48   a . Clamp  40  preferably further includes screw  46  for applying a downward force to cantilever element  50   c , thereby rotating jaw  50  about central fulcrum  50   b , which preferably comprises pin  30 .  
      Preferably, clamp  40  also comprises body  42  that provides a structure upon which the components of clamp  40  are mounted to stabilize clamp  40  and to provide a supporting structure for the lever/fulcrum system. To lock jaw  50  of clamp  40  onto cargo ring  110 , or other securement point structure, clamp  40  preferably has locking screw  120  ( FIGS. 4-6 ), such as a thumb screw, that engages bridge  44 , thereby preventing screw  46  from loosening and maintains the force applied thereby to cantilever element  50   c.    
      To more fully illustrate the components of clamp  40 , reference is drawn to  FIG. 4 . Body  42  of clamp  40  is preferably milled from steel, though it is considered to be within the scope of the present invention to optionally use similar metals or compounds having physical properties similar to steel. It will be further appreciated that alternative methods of manufacture, of this and all other parts of the present invention, are contemplated, such methods comprising castings, stampings, or the like. Body  42  preferably includes protruding hooks  82   a, b  and respective workpiece contacting surfaces  48   b, c  which form workpiece contacting surface  48   a  (described above with reference to  FIG. 3 ). Workpiece contacting surface  48   a  preferably has commensurate shape and size to permit cargo ring  110 , or other securement point structure, to be inserted into workpiece contacting surface  48   a , as shown more fully in  FIGS. 5 and 6 .  
      Jaw  50  of clamp  40  preferably includes semi-circular receiving notch  34 . Receiving notch  34  preferably acts in conjunction with hooks  82   a, b  to secure cargo ring  110  therebetween (best seen with reference to  FIGS. 5 and 6 ). To provide the necessary compressive and/or restraining forces to prevent outside forces from extracting cargo ring  110  from clamp  40 , central fulcrum bore  82  is preferably disposed through jaw  50 . When pressed against surface  32  of cantilever element  50   c , screw  46  preferably pushes notch  34  upwards by rotation about pin  56 , inserted through aperture  66  and fulcrum bore  82  and held in place by cotter pin  58 .  
      To maintain the force imparted by screw  46  onto surface  32 , preferably bridge  44  is provided. Screw  46  is preferably threaded through threaded aperture  80 . Bridge  44  is preferably rotatably connected to clamp body  42  by pin  60 . Pin  60  is preferably inserted into receiving pin  70  through apertures  78 ,  72 , and  64  (and a corresponding aperture not shown). To facilitate the rotation of bridge  44 , washers  62 ,  74 ,  76 , and  68  are preferably provided.  
      When screw  46  is tightened to push surface  32  of cantilever element  50   c  downward, preferably imparting a resulting upward force on surface  34  of workpiece end  50   a , through fulcrum  50   b , receiving passageway  48   b, c , hooks  82   a, b , and workpiece contacting surface  48   a  preferably clamp onto cargo ring  110 .  
      For purposes of illustration only, the securement element discussed herein is cargo ring  110 , as shown by example in  FIGS. 2, 5  and  6 , having a generally circular shape attached at a point to a conveyance, most preferably an aircraft. It should be appreciated by those of ordinary skill in the art that the present invention may optionally be used on, or in association with, a variety of types of securement points and/or conveyances.  
       FIG. 5  is a top-down view of the present invention clamped onto a typical aircraft securement point, such as cargo ring  110 . As shown, when locking element  44  screw  46  is tightened, cargo ring  110  is preferably secured within the jaw of clamp  40 . Further, in a preferred embodiment of the present invention, when cargo ring  110  is secured within clamp  40 , adapter plate  90 , which is removably attached to clamp  40 , is preferably securely seated flat onto surface  100  in which the securement point is attached, in this example the cargo floor of an aircraft. Having adapter plate  90  seated securely onto surface  100  when clamp  40  is preferably engaged with cargo ring  110  preferably provides for a securement point that resists forces in, and about, all axes of possible movement.  
       FIG. 6  is a side view showing cargo ring  110  secured within the jaw of clamp  40 . As described above, in a preferred embodiment of the present invention, clamp  40  is preferably sized so that when cargo ring  110  is secured by clamp  40 , adapter plate  90  is preferably pressed firmly against surface  100  in which cargo ring  110  is attached.  
       FIG. 7  shows more fully how adapter plate  90  is preferably attached to clamp  40 . As shown, adapter plate  90  is preferably a unitary piece having various portions to provide for the present invention. More specifically, adapter plate  90  preferably has projections  92   a - d  which mate with four corresponding apertures on the underside face of clamp  40  (not shown). When properly aligned, adapter plate  90 , through projections  92   a - d , is preferably fixedly engaged with clamp  40 . Alternatively, projections  92   a - d  may be replace by apertures, and adapter plate  90  may be screwed, or otherwise mechanically fastened to clamp  40 . Further, adapter plate  90  preferably also has slot  94  and extension surface  96  which allows the securement point of the prior figures to be aligned with the jaw of clamp  40  and slide into the jaw when opened; thus, providing for an opening for extending the securement point to the opening of the jaw of clamp  40 .  
      Additionally, in a preferred embodiment of the present invention, adapter plate  96  also has surface  98  which is preferably disposed substantially perpendicular to surface  105 . Surface  98  preferably has apertures  102   a - d  (aperture  102   d  not shown) through which a load may be secured to adapter plate  90 . As discussed previously, when clamp  40  is engaged with a securement point (not shown), surface  105  is preferably securely engaged with surface  100 .  FIG. 8  shows the underside of the preferred embodiment of the present invention.  FIG. 9  shows the side view of the preferred embodiment of the present invention.  FIG. 10  is a backside view of the preferred embodiment of the present invention.  
      Because load securement devices may vary, various types of adapter plates may be necessary in order to secure the load to the clamp of the present invention. As an example,  FIG. 11  shows clamp  40  preferably secured to C-channel adapter plate  1100 . C-channel adapter plate  1100  is preferably a unitary piece having a shape similar to the shape of adapter plate  90  of the prior figures, further including an additional perpendicular surface. As shown, adapter plate  1100  preferably has perpendicular surfaces  1102   a,b  that allow the cargo to be secured to the present invention, and that utilize a C-channel cargo securement apparatus.  FIG. 12  shows the underside of adapter plate  1100  having surfaces  1202   a,b.    
      Another embodiment of the present invention is shown more fully in  FIG. 13 . For instances in which a load needs to be secured to multiple securement points, due to various requirements, including, for example, space limitations and/or design considerations,  FIG. 13  shows an alternative embodiment of the present invention in which clamps  1340   a,b  are preferably secured within tubular adapter  1304 . Clamps  1340   a,b  are constructed similarly to clamp  40 , as described above. When engaged to two securement points, adapter  1304  preferably provides a load securement point that is stronger than may be provided using a single clamp.  FIG. 14  is a cutaway side view showing clamp  1440   a  secured within adapter  1404 .  FIG. 15  is a perspective view showing clamps  1440   a,b  secured within adapter  1404 .  
      Having, thus, described exemplary embodiments of the present invention, it should be noted by those skilled in the art that the within disclosures are exemplary only and that various other alternatives, adaptations, and modifications may be made within the scope and spirit of the present invention. Accordingly, the present invention is not limited to the specific embodiments as illustrated herein, but is only limited by the following claims.