Abstract:
A backpack load transfer and stabilization system includes a roll control rod coupled to a hip belt for a backpack. The control rod is contained entirely within the hip belt and extends across the width of the hip belt. The control rod is coupled, in turn, to semi-rigid extension members which serve as the interface between the hip belt and t he main backpack. The extension members transfer the load to locations on the hip belt corresponding to hip locations of the person wearing the backpack. The extension members are rotatably coupled to the main backpack and rigidly coupled to the roll control rod, such that when a person wearing the backpack hikes, and the person&#39;s hips move up and down, the combination of the roll control rod and interconnected extension sections compensate for the up-and-down movement of the hips to stabilize the load and prevent side-to-side swaying.

Description:
TECHNICAL FIELD  
         [0001]    This invention relates to backpacks, and more particularly to load transfer and stabilization systems for backpacks.  
         BACKGROUND OF THE INVENTION  
         [0002]    Backpacks have long been used to carry loads and materials of all types. To make the backpack loads easier to haul, improvements to backpacks have continually been made to increase their efficiency, functionality, and comfort.  
           [0003]    To create a backpack that is easier and more comfortable to carry, hip belts were developed many years ago. Hip belts are intended to transfer a portion of the load from the shoulders to the hips of the person wearing the backpack. Numerous different types of hip belts have existed over the years.  
           [0004]    One problem associated with traditional hip belts is that the weight of the pack tends to focus on the mid-point of the hip belt, which is aligned with the center of the back (i.e., the backbone) of the person wearing the pack. When the backpack weight focuses on the mid-point of the hip belt, it tends to sag toward the middle and the load is not effectively transferred to the hips of the person wearing the backpack. One potential solution of the problem of sagging toward the middle of the hip belt would be to create a rigid hip belt, which would create cantilevers running toward each hip area of the belt. This, however, would add weight and unnecessary rigidity to the hip belt, making the hip belt less comfortable.  
           [0005]    Attempts have been made to transfer the backpack load to the hip belt at locations adjacent the hips of the person wearing the backpack. One example of such a system has been created by Dana Design. Certain Dana Design backpacks include fiberglass rods extending from the shoulder strap areas to locations on the hip belt corresponding to the hips of a person wearing the backpack. Such a fiberglass rod will be found on each side of the backpack. The fiberglass rods serve to transfer the load from the shoulder strap areas to the hip belt at locations proximate to the wearer&#39;s hips.  
           [0006]    Still another problem with traditional backpack designs is that they fail to provide a solution for side-to-side stabilization of the load. Since at least a portion of the backpack is supported at the wearer&#39;s hips, when a person walks or hikes, lifting a foot necessarily involves lifting the corresponding hip. Each time a person&#39;s hip rises, the backpack tends to shift laterally, particularly at the top end of the backpack, toward the opposite side. This causes the load to sway from one side to another as the person walks or hikes, lifting and lowering sequentially each of the hips. As the backpack sways from side-to-side, the hip belt, rigidly attached to the backpack cargo compartment, moves up and down at each hip location. This becomes tiring and quite uncomfortable over time and results in additional wear and tear on the backpack.  
           [0007]    In view of the foregoing, there is a need to develop a backpack load transfer and stabilization system that will effectively transfer a load to hip locations on the hip belt, compensate for up-and-down movement of a person&#39;s hips while carrying the backpack, and maintain stationary the attachment locations between the backpack and the hip belt to increase comfort for the backpack wearer.  
         OBJECTS AND SUMMARY OF THE INVENTION  
         [0008]    A primary object of the invention is to provide an effective load transfer and stabilization system for backpacks.  
           [0009]    Another object of the invention is to provide a load stabilization and transfer system for a backpack to transfer a portion of the load to the hips and compensate for the rise and fall of the hips of the person wearing the backpack.  
           [0010]    Still another object of the invention is to provide a backpack load transfer and stabilization system that transfers the load to the hips, yet stabilizes the load by dynamic interaction between hip-supporting areas while the backpacker walks.  
           [0011]    Another object of the invention is to provide a backpack load transfer and stabilization system which involves a resilient roll control rod attached to opposed generally triangularly shaped extension members which dynamically and interactively shift and transfer the load outwardly toward the hips, with the roll control rod causing the extension members to interact with each other to stabilize the load while a wearer walks with the backpack.  
           [0012]    Yet another object of the invention is to provide a backpack load stabilization and transfer system that will support that load at stationary locations on a hip belt by providing a roll control rod attached to opposed extension members which interactively compensate for the side-to-side sway of the backpack as a person carrying the backpack walks.  
           [0013]    Another object of the invention is to provide a backpack load transfer and stabilization system to transfer the backpack load from attachment locations interconnecting the backpack to the cargo compartment to extended locations on the hip belt corresponding to the wearer&#39;s hips.  
           [0014]    Still another object of the invention is to provide a backpack load transfer and stabilization system to simultaneously transfer the weight of the backpack to locations on a hip belt corresponding to the wearer&#39;s hips and stabilize the side-to-side sway of the backpack as the wearer walks.  
           [0015]    The foregoing objects of the invention are achieved by a backpack load transfer and stabilization system according to the present invention. The load transfer and stabilization system comprises a roll control rod, encased in a webbing pocket sewn into the hip belt, coupled to opposed semi-rigid extension members. The roll control rod forms an arc having an apex toward the top of the hip belt. The roll control rod is contained entirely within the hip belt. The pair of extension members or wings are operatively coupled to the ends of the roll control rod. These extension sections are coupled, in turn, to attachment locations interconnecting the cargo compartment of a backpack with the hip belt. The attachment locations allow for pivotal movement between the extension members rigidly coupled to the hip belt and the cargo compartment. The extension members transfer the load from the attachment location to locations farther out on the hip belt corresponding to the hips of the person wearing the backpack. The roll control rod interactively connects the extension members so that movement of one (which results from movement of the corresponding hip of the backpack wearer) results in a reactive movement of the other to stabilize the load when the wearer walks and moves his or her hips up and down.  
           [0016]    Other objects, features, and advantages of the invention will become apparent from the following detailed description of the invention with reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    Preferred embodiments of the invention are described below with reference to the accompanying drawings:  
         [0018]    [0018]FIG. 1 is a rear perspective view of a conventional backpack apparatus incorporating a load transfer and stabilization system according to the present invention;  
         [0019]    [0019]FIG. 2A is a front elevation view of a load transfer and stabilization system (without the hip belt) according to the present invention showing the configuration of the system when the backpack wearer lifts his or her right leg and hip;  
         [0020]    [0020]FIG. 2B is a front elevation view of a load transfer and stabilization system (without the hip belt) according to the present invention showing a stationary position of the system when neither of the hips of the backpack wearer is moving;  
         [0021]    [0021]FIG. 2C is a front elevation view of a load transfer and stabilization system (without the hip belt) according to the present invention showing the configuration of the system when the backpack wearer lifts his or her left leg and hip;  
         [0022]    [0022]FIG. 3 is a front elevation view of a hip belt for a backpack with a load transfer and stabilization system with the backpack&#39;s vertical and transverse stays shown according to the present invention mounted thereto;  
         [0023]    [0023]FIG. 4 is a front elevation view of a hip belt for a backpack showing the load transfer and stabilization system of the present invention as it moves between various load stabilization positions;  
         [0024]    [0024]FIG. 5 is a front perspective view of a hip belt for a backpack incorporating a load transfer and stabilization system according to the present invention;  
         [0025]    [0025]FIG. 6 is a rear perspective view of a hip belt for a backpack incorporating a load transfer and stabilization system of the present invention;  
         [0026]    [0026]FIG. 7 is a sectional side view, taken along the lines  7 - 7  of FIG. 5, of the flexible, resilient roll control rod sewn into a pocket or webbing which is sewn, in turn, to a rigid lumbar plate to form a part of the load stabilization system according to the present invention;  
         [0027]    [0027]FIG. 8 is a sectional view, taken along line  8 - 8  of FIG. 3, of one preferred method of securing the various stay-lumbar plate structures to a backpack apparatus used in connection with the present invention;  
         [0028]    [0028]FIG. 9 is a perspective view of the backpack load transfer and stabilization system of FIG. 5, with additional features of the hip belt and load transfer and stabilization system shown;  
         [0029]    [0029]FIG. 10 is a perspective view of the load transfer and stabilization system of FIG. 9;  
         [0030]    [0030]FIG. 11 is a front view of an alternative embodiment of a load transfer and stabilization system incorporated into a hip belt for backpacks according to the present invention;  
         [0031]    [0031]FIG. 12 is a front view of yet another alternative embodiment of a load transfer and stabilization system incorporated into a hip belt for a backpack according to the present invention; and  
         [0032]    [0032]FIG. 13 is a sectional view, taken along the line  13 - 13  of FIG. 12, showing the various interconnecting elements between the load transfer and stabilization system and the hip belt for a backpack. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0033]    The present invention is intended for use in connection with a backpack apparatus  10 , as shown in FIG. 1. While FIG. 1 shows a so-called internal frame backpack  10 , it is to be understood that the present invention may be utilized with virtually any type of backpack apparatus where a hip belt is utilized.  
         [0034]    A conventional backpack apparatus  10  includes, among other things, a main pack or payload or cargo compartment  12 , shoulder straps  14 , a hip belt  16 , and a buckle  18  for the hip belt. Virtually all backpacks used for hiking, mountaineering, and the like include these conventional elements. The specific construction of conventional aspects of a backpack apparatus suitable for the present invention will be known to those skilled in the art.  
         [0035]    The present invention relates to load transfer and stabilization system  20  (FIG. 1) for backpacks  10 . The load transfer and stabilization system  20  is to be utilized in connection with the hip belt  16  of the backpack apparatus  10 . With reference to FIGS. 5 and 6, the load transfer and stabilization system  20  is integrally incorporated into the hip belt  16 . The hip belt, having a height and a width, completely holds the load transfer and stabilization system. The system is more specifically incorporated into a side of the hip belt adjacent the cargo compartment  12  (FIG. 1) of the backpack apparatus  10 . The portion of the hip belt  16  that comes in contact with the wearer&#39;s lumbar and hip area when wearing the backpack (FIG. 6) comprises a conventional foam pad over which a suitable material, such as nylon or another synthetic fabric, is secured. The inner lining or surface of the hip belt  16  may be made of spandura or other suitable material, and may include a gripping surface.  
         [0036]    With reference to FIG. 5, the roll control apparatus  20  comprises a flexible stabilizer in the form of a resilient rod  22 , made preferably of delron or another suitable resilient material. The stabilizer or rod arcs upwardly to form an apex in close proximity to an upper edge of the hip belt. The ends of the rod  22  terminate below a middle line (relative to the top and bottom) of the hip belt. The rod  22  is held within a sheath of cloth material  23  sewn or otherwise secured to the outer surface of hip belt  16 . While the rod  22  preferably comprises a circular cross-sectional shape, as shown in FIG. 7, it is to be understood that the term “rod” is intended to cover all cross-sectional shapes of resilient, rod-like members that may be used in connection with the present invention. The flexible rod  22  terminates at ends  22   a ,  22   b  (FIGS.  2 A- 2 C, and  3 - 4 ), each of which is attached to respective wings or extension pieces  24 ,  26 . A fabric sheath  23  (FIG. 7) is used to hold the rod  22  in position. A main fabric border  25  (FIG. 5) is sewn below the sheath  23  and interfaces between rod  22  and extension pieces  24 ,  26 . While the flanged extension pieces may be made of any suitable rigid material, preferably a high density polyethylene or another suitable synthetic material is used. The flanged extension portions or wings  24 ,  26  are generally triangularly shaped. The extension pieces  24 ,  26   b  are secured to the hip belt by additional peripheral fabric pieces  27 ,  29 , which ultimately join and are sewn or otherwise secured to the main fabric piece  25 . Fabric pieces  27 ,  29  cover the edges of the rigid material comprising the flanged extension pieces  24 ,  26 , which can be rough and capable of cutting anything it contacts—especially when bearing a load such as during backpacking.  
         [0037]    As shown in FIGS.  2 - 5 , the extension members  24 ,  26  further comprise fastening or mounting locations  28 ,  30 , respectively. Fastening locations  28 ,  30  provide areas for attaching the flanged extension portions to the lower end of a backpack cargo compartment  12  (FIG. 1). In the embodiment of FIG. 5, grommets  32 ,  34  are secured to the extension members to define fastening locations  28 ,  34 . Pins, bolts, rivets, or other fastening members (not shown) may be inserted through grommets  32 ,  34  and secured to the main compartment  12  of the backpack  10  to couple the hip bet  16  via extension pieces  24 ,  26 , to the cargo compartment  12  of the backpack  10 . The fasteners allow the extension members  24 ,  26  to articulate relative to mounting locations  36 ,  38 .  
         [0038]    As shown in FIG. 4, when a person wears a backpack with the hip belt  16  secured around his or her waist and hips, moment arms are created between mounting location  36  and roll control rod end  22   b , and between mounting location  38  and roll control rod end  22   a . These lever arms work to transfer the load out further toward the extreme ends of the hip belt, to locations corresponding to the wearer&#39;s hips. When the wearer of the backpack walks, the right hip will move up (RU) and down (RD), and the left hip will move up (LU) and down (LD). As the right hip moves up, for example, to the position (RU), the end  22   b  of the roll control rod moves up and the roll control rod flexes to a skewed left position (LP), which results in the end  22   a  of the roll control rod moving down. Because the extension pieces  24 ,  26  are secured together via the roll control rod  22 , they are interactive relative to one another. When one of the roll control rod ends  22   a ,  22   b  moves up or down, the other roll control rod end moves in an opposite direction. Where the entire roll control apparatus  20  is held within the hip belt (i.e., the upward arc of the roll control rod  20  does not extend beyond the height of the hip belt), the up-and-down motion for the hips is compensated for by the load transfer and stabilization system. The extension pieces  24 ,  26  dynamically and interactively move relative to one another about mounting locations  36 ,  38 , while mounting locations  36 ,  38  remain relatively stationary. This results in a stabilized load, while achieving the benefits of a load transferred to the hips of the person wearing the backpack.  
         [0039]    With reference to FIGS.  2 A- 2 C, the center point (CP) of the roll control rod and its changes, depending on movement of the wearer&#39;s hips, can be seen. In FIG. 2A, the person&#39;s right hip elevates at roll control rod end  22   b , which shifts the center point (CP) toward the left relative to a neutral position (shown in FIG. 2B). In response, the opposed end  22   a  is lowered. Both of the extension members  24 ,  26  rotate counterclockwise relative to mounting locations  28 ,  30 , respectively. The opposite occurs when the left hip is raised, which correspondingly raises roll control rod end  22   a , lowers roll control rod  22   b , and shifts the center point (CP) toward the right relative to the neutral center point (CP) position (shown in FIG. 2B). Extension pieces  24 ,  26  rotate clockwise relative to mounting locations  28 ,  30 , respectively.  
         [0040]    With reference to FIGS. 3, 4, and  8 , the hip belt  16 , with the associated roll control apparatus  20 , is attached to the cargo compartment  12  of the backpack apparatus  10  (FIG. 1) via mounting locations  28 ,  30 , as discussed above. Mounting pins or other suitable fasteners  36 ,  38  extend through the grommets  32 ,  34  (FIG. 5) and ultimately through a horizontal crossbar  40  (FIG. 3) to interconnect the hip belt with the cargo compartment of the backpack. As shown in FIG. 8, the crossbar  40  is held in place by a piece of fabric  44  sewn to the lumbar plate  45 , which is secured, in turn, to the cargo compartment  12  of the backpack apparatus  10  (FIG. 1). The lumbar plate  45  is preferably made of high density polyethylene, but other suitable semi-rigid material may be utilized. The horizontal crossbar  40  is also operatively coupled to lower ends of vertically oriented stays  42 ,  44  (which converge toward the bottom of hip belt  16  to form a V-shaped configuration) by fabric pieces (not shown in FIG. 3) sewn into the lumbar plate  45 . The V-configured frame diverges toward the top of the backpack to correspond to the relatively wider shoulders of the backpack wearer and converges toward the bottom to correspond to the wearer&#39;s waist. The sizes (i.e., the cross-sectional dimensions and lengths of the stays) may vary to provide a custom fit. The stays are preferably made of 6061/T6 aircraft aluminum.  
         [0041]    Although not shown in the drawings, a lumbar pad is intended to be utilized in connection with the hip belt. Unlike conventional lumbar pads, however, a lumbar pad may be installed between the hip belt  16  and the cargo compartment  12  when used with the present invention. A preferred lumbar pad may comprise of a single piece of material or layers of material, which can be selectively used by the wearer.  
         [0042]    [0042]FIG. 8 shows the cross-sectional details of a fabric piece  41  sewn to the high-density polyethylene lumbar plate  45  to hold the transverse stay  40  in place at the bottom of the backpack cargo compartment. A lower flap  56  and an extension flap  54  integrally extend from the main backpack to secure the lumbar plate  45  to the backpack. A velcro fastener  55  holds the lumbar plate  45  in the proper location on the backpack. Fabric pieces (not shown) for the vertical stays  42 ,  44  secure the vertical stays in their V-shaped orientation directly to the high-density polyethylene lumbar plate  45 . The stays can be removed from the pockets formed by the fabric pieces to be replaced by different stays for custom fitting purposes.  
         [0043]    The stay-lumbar plate construction results in a unitary assembly comprising the transverse bar  40 , the vertical stays  42 ,  44 , and the lumbar plate  45 . The purpose of this configuration is to ensure that the load is appropriately translated to the hip belt and the inventive load transfer and stabilization apparatus.  
         [0044]    In operation, the present invention results in support of the main backpack or cargo compartment  12  at two locations on the hip belt—mounting locations  28  and  30 . These are the only two areas where the hip belt is mounted to the cargo compartment. The triangular-shaped high density polyethylene extension sections or wings  24 ,  26  transfer the load further toward the extreme ends of the hip belt to a position closer to areas on the hip belt that correspond to the wearer&#39;s hips. In essence, a moment arm is created between mounting location  28  and end  22   b  of roll control rod  22 , and between mounting location  30  and end  22   a  of the roll control rod  22 . These moment arms transfer the load out from the mounting locations  28 ,  30  to the ends  22   a ,  22   b  of the roll control rod  22 , which corresponds to the hips of the person wearing the backpack. The result is increased comfort for the wearer and a more stable load.  
         [0045]    Utilization of the present invention results in a stabilized backpack load that accommodates for the rise and fall of a person&#39;s hips while hiking. FIGS.  2 A- 2 C (described above) show a sequence of the load transfer and stabilization system and sequential positions of the roll control rod  22  and the attached extension pieces  24 ,  26  when a person wearing the backpack walks. The extension members  24 ,  26  rotate relative to mounting locations  28 ,  30 , yet the vertical positions of mounting locations  28 ,  30  remain relatively stationary. This results in a more comfortable stable load.  
         [0046]    [0046]FIGS. 9 and 10 show additional aspects of the combined hip belt  16  and roll control apparatus  20  as shown in FIGS.  1 - 6 . A pair of straps  60 ,  62  may be secured at attachment locations  28 ,  30  so that they can be, in turn, secured to shoulder straps  14  (FIG. 1). Alternatively, or in combination with straps  60 ,  62 , fastening locations  72 ,  74  (FIG. 10) may be utilized to attach the combined hip belt  16 /roll control rod apparatus  20  to a main compartment of a backpack (not shown in FIGS. 9 and 10).  
         [0047]    The frame sheet or lumbar plate  45  (FIGS. 3, 9, and  10 ) is preferably covered by a fabric material  64  about its periphery to prevent the relatively rough edges of the high density polyethylene from cutting other portions of the backpack and perhaps the clothes of the person wearing the pack. A pair of pockets  66 ,  68  (FIG. 9) are sewn into the lumbar plate  45  to provide insertion locations for the vertical stays  42 ,  44 . To ensure that the lumbar plate  45  does not articulate too much away from the hip belt  16  at pivot points  28 ,  30 , a limit strap  70  (FIG. 9) may be adjustably mounted between the hip belt  16  and the lumbar plate  45 . It should be noted that FIG. 10 shows the lumbar plate  45  being folded or bent beyond what is normally intended for purposes of illustrating the back side of lumbar plate  45 . As mentioned, strap mounting locations  72 ,  74  (FIG. 10) are provided so that the main pack  12  (FIG. 1) can be further secured to the hip belt via the lumbar plate  45 .  
         [0048]    [0048]FIG. 11 shows an alternative embodiment to the present invention. Rather than mounting locations  28 ,  30  as utilized in connection with the embodiments shown in FIGS.  1 - 10 , the vertical stays  42 ,  44  are held inside of pockets  80 ,  82  sewn to a lumbar plate  84  which is sewn, in turn, into a fabric panel  86  along a single line of stitching  85  which runs along the entire length of lumbar plate  84  immediately below roll control rod  20 . Thus, the lumbar plate  84  is capable of articulating relative to panel  86  about stitching line  85 . The frame sheet or lumbar plate  84  includes a peripheral piece of fabric  88  which is utilized to cover the edges of the lumbar plate  84 . The combined lumbar plate and peripheral fabric piece  88  are sewn into panel  86 , as mentioned, along sewing or stitching line  85  to hold the entire assembly together. Much like the roll control apparatus  20  shown in FIGS.  1 - 10 , the roll control apparatus shown in FIG. 11 will operate to stabilize the load and compensate for the rise and fall of the hips of the person wearing the backpack. The action of load transfer and stabilization will take place along stitching line  85 . To ensure the appropriate dynamics, the lumbar plate  84  is sewn to the bottom of the material covering the roll control rod  20  so that the benefits of the roll control rod  20  can be achieved.  
         [0049]    Still another embodiment of the present invention is shown in FIG. 12. A single vertical stay  90  is inserted into a pocket  92  sewn into a uniquely configured frame sheet or lumbar plate  94 . The lumbar plate  94 , similar to lumbar plate  45  shown in FIG. 3 and lumbar plate  84  shown in FIG. 11, is comprised of high density polyethylene. Lumbar plate  94  is narrow toward the bottom and gradually increases in width until it connects with the roll control rod  20 . A fabric edge cover piece  96  is sewn directly to the cover  23  encapsulating roll control rod  20  along stitching line  95 . The top edge of lumbar plate  94  and the bottom of roll control rod  20  are adjacent to and engaged with one another to provide substantially the same benefits associated with the roll control rod  20  shown and comprised with respect to FIGS.  1 - 9 . Straps  60 ,  62  may be connected, in turn, to shoulder straps  14  (FIG. 1), which are sewn to a panel  98  at locations  61 ,  63 . Panel  98  also provides a location for securing roll control rod  20 .  
         [0050]    [0050]FIG. 13 shows a sectional view of the roll control apparatus of FIG. 12. The roll control rod  20  and its enveloping fabric  23  are secured to the hip belt  16  at stitching location  25 . The lumbar plate  94  is attached to the hip belt  16  through fabric edge piece  96  at a single stitching line or location  95 . Thus, lumbar plate  94  articulates relative to hip belt  16  at stitch line  95 . This forms a flap-type of mounting arrangement. The main compartment  12  of the backpack is secured to the frame sheet  94  by means of an attachment flap  100  which includes a Velcro-type fastener and is secured, in turn, to a section of fabric  101  with a corresponding Velcro-type fastener. Fabric piece  101  is secured to the back side of lumbar plate  94 . In addition, stay  90  is inserted into a pocket  92  which will hold a substantial portion of the weight of the main compartment  12  of the backpack. To further secure the pack in place, a piece of fabric  102  with a Velcro-type fastening mechanism is secured to the backside of stay  90  so that it can be secured, in turn, to a piece of fabric  104  with a Velcro-type fastening mechanism. Fabric piece  104  is secured to the lumbar plate by means of a piece of fabric  105 , as shown in FIG. 13. As shown in FIG. 12, the top edge of lumbar plate  94  is secured adjacent to and engaged with the roll control rod  20  so that the load transfer and stabilization benefits can be achieved, similar to what has been described with respect to the other embodiments of the present invention.  
         [0051]    While this invention has been described with reference to certain specific embodiments and examples, it will be recognized by those skilled in the art that many variations are possible without departing from the scope and spirit of this invention. The invention, as described by the claims, is intended to cover all changes and modifications of the invention which do not depart from the spirit of the invention. The words “including” and “having,” as used in the specification, including the claims, shall have the same meaning as the word “comprising.”