Abstract:
A backpack frame comprising a plurality of flexible support members wherein each of the plurality of flexible support members further comprise a top end and a bottom end, a pack further comprising a first tensioner attachment point and a second tensioner attachment point, and a plurality of tensioners wherein each of the plurality of tensioners further comprises a tension length. One of the plurality of tensioners is attached to the first tensioner attachment point and also attached to the second tensioner attachment point. One of the plurality of flexible support members extends substantially between the first tensioner attachment point and the second tensioner attachment point. The tension length of one of the plurality of tensioners is located between the first tensioner attachment point and the second tensioner attachment point. The tension length may be adjusted.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of backpack frames. More specifically, the present invention relates to lightweight backpack frames that include flexible supports that may bow under tension. 
       BACKGROUND OF THE INVENTION 
       [0002]    Backpack frames have traditionally been rigid structures to which a pack is secured. Traditional backpack frames distribute the load of the pack to the wearer&#39;s hips and bring the pack in contact with the wearer&#39;s back. This construction has been unsatisfactory as it is uncomfortable for the wearer to have the pack in contact with his or her back. The close proximity of the pack to the wearer&#39;s back prevents air from circulating in the area and cooling the wearer. Additionally, the contents of the pack may exert pressure on the wearer&#39;s back causing additional discomfort for the wearer. 
         [0003]    Another difficulty with these prior backpack frames is that they are generally complex in structure and expensive to manufacture. Since these frames are generally constructed of materials that are permanently secured together, the frame cannot be reduced in size for storage or flattened for easier transport or storage. 
         [0004]    It is therefore an object of my invention to provide a backpack frame that may be easily assembled and disassembled in the field without special tools, that may be easily flattened for storage or transport, and that, when applied to the back of a wearer, will avoid any hard surface contact with the body while at the same time distributing the weight of the pack to the wearer&#39;s hips. 
       SUMMARY OF THE INVENTION 
       [0005]    With the foregoing in mind, embodiments of the present invention are related to a lightweight, adjustable backpack frame. Furthermore, the backpack frame may advantageously combine flexible support stays with an adjustable tensioner. 
         [0006]    According to an embodiment of the present invention, a backpack frame may be constructed from a pair of flexible support members with tensioners attached to each end of the flexible support members. These flexible support members may be constructed of a material that flexes. Specifically, the flexible support members may be constructed of a lightweight material that resiliently flexes when exposed to stress. The flexible support members may remain rigid when exposed to forces that extend through the flexible support member substantially perpendicular to the top end and the bottom end. The flexible support members may flex or bow into an essentially arcuate shape when exposed to lateral forces that deflect the area of the flexible support member disposed between the top end and the bottom end while applying force to bring the top end and the bottom end in closer proximity to one another. When these forces are removed, the flexible support member may return to its original, essentially planar shape. 
         [0007]    Each flexible support member may be connected to a pack by a top capture and a bottom capture. The top capture or the bottom capture may be a rivet or any fastener known to those skilled in the art. In one embodiment, the top capture or bottom capture may be constructed from ruggedized fabric that is secured to the pack on the left side and the right side of the flexible support member. In another embodiment, the top capture or bottom capture may be constructed from ruggedized fabric that is secured to the pack on the left side and the right side of the flexible support member as well as above the top end for a top capture and below the bottom end for a bottom capture. The top capture or bottom capture may removably connect the flexible support member to the pack. This may be achieved by connection methods including, but not limited to, hooks and loops, snaps, rivets, buttons, zippers, securing pockets, or the like. 
         [0008]    A tensioner attachment point may be disposed on the pack. The tensioner attachment point may be disposed in close proximity to each top end and each bottom end. The tensioner attachment point may connect to the pack at the same location as the top capture or bottom capture. Two tensioner attachment points may be disposed on the pack for each flexible support member that is present. 
         [0009]    A tensioner may connect to two tensioner attachment points. The tensioner may be a rope-like structure constructed from a synthetic material that resists elongation when subject to tensile stress. The tensioner may have a tension length that is measured as the length of tensioner disposed between the two tensioner attachment points to which the tensioner is connected. 
         [0010]    The tensioner length may be adjusted to manipulate the shape of the flexible support member across which the tensioner is disposed. When the tensioner length is at maximum length, which is any length longer than the length of the flexible support member across which the tensioner is disposed, the flexible support member may maintain a substantially planar shape. When the tensioner length is adjusted to an activating length, which is any length shorter than the length of the flexible support member across which the tensioner is disposed, the flexible support member may be subject to forces that draw the top end and the bottom end closer together and cause the flexible support member to assume an arcuate shape. 
         [0011]    In one embodiment of the inventive backpack frame there may be two flexible support members, two tensioners, two top captures, two bottom captures, and four tensioner attachment points. In such an embodiment, the tension length of each tensioner may be adjusted independently. In such an embodiment, the two flexible support members may be disposed substantially parallel to one another. The two flexible support members may be substantially identical in length. The top captures may be disposed at substantially the same height on the pack and the bottom captures may be disposed at substantially the same height on the pack. 
         [0012]    The tensioner may be connected to the tensioner attachment point by threading the tensioner through a first opening of an attachment apparatus and a second opening of an attachment apparatus. The tensioner may pass through the first opening substantially 180° opposed to the direction at which it may pass through the second opening. The tensioner may be secured in place by the attachment apparatus through friction, clamping, or the like. The tensioner length may be adjusted by pulling on either free end of the tensioner. The force exerted by the attachment apparatus may be removed from the tensioner to allow the tension length to increase. 
         [0013]    A cross-member may extend between two or more flexible support members. In embodiments utilizing a cross-member, the cross-member may connect substantially orthogonally to each flexible support member. The cross-member may be constructed from a material similar to that of the flexible support member. However, it may not be necessary for the cross-member to flex. The cross-member may be resiliently flexible or rigid. In some embodiments of the inventive backpack frame, a cross-member may connect two flexible support members at or near the top ends while a second cross-member may connect the two flexible support members at or around their mid-points. 
         [0014]    A mesh structure may extend substantially between two or more tensioners. The mesh structure may be substantially planar and provide a breathable surface to come into contact with a wearer&#39;s back when the backpack is in use. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a perspective drawing of the backpack frame. 
           [0016]      FIG. 2   a  is a drawing of one embodiment of the top capture. 
           [0017]      FIG. 2   b  is a drawing of another embodiment of the top capture. 
           [0018]      FIG. 2   c  is a drawing of a cross-member capture. 
           [0019]      FIG. 3  is a drawing of the backpack frame on a wearer&#39;s back. 
           [0020]      FIG. 4  is a drawing of the tensioner attachment point. 
           [0021]      FIG. 5   a  is a drawing of the tensioner at the activating length. 
           [0022]      FIG. 5   b  is a drawing of the tensioner at the maximum length. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0023]    The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Those of ordinary skill in the art realize that the following descriptions of the embodiments of the present invention are illustrative and are not intended to be limiting in any way. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Like numbers refer to like elements throughout. 
         [0024]    In this detailed description of the present invention, a person skilled in the art should note that directional terms, such as “above,” “below,” “upper,” “lower,” and other like terms are used for the convenience of the reader in reference to the drawings. Also, a person skilled in the art should notice this description may contain other terminology to convey position, orientation, and direction without departing from the principles of the present invention. 
         [0025]    Referring to  FIG. 1 , a backpack frame  100  is shown. As depicted, there is a pair of flexible support members  101 . These flexible support members  101  may be constructed of a material that flexes. Specifically, the flexible support members  101  may be constructed of a lightweight material that resiliently flexes when exposed to lateral stress. Suitable materials for the flexible support members include, but are not limited to, carbon fiber, aluminum, wood, or the like. In one embodiment of the inventive concept, the flexible support members  101  may be constructed from carbon fiber rods, blades, or the like. The flexible support members  101  may be solid or hollow. 
         [0026]    Each flexible support member  101  may have a top end  102  and a bottom end  103 . The flexible support members  101  may remain rigid when exposed to forces that extend through the flexible support member  101  directly between the top end  102  and the bottom end  103 . The flexible support members  101  may flex or bow into an essentially arcuate shape when exposed to lateral forces that deflect the area of the flexible support member  101  disposed between the top end  102  and the bottom end  103  while applying force to bring the top end  102  and the bottom end  103  in closer proximity to one another. When these forces are removed, the flexible support member  101  may return to its original, essentially planar shape. 
         [0027]    Each flexible support member  101  may be connected to a pack  104  by a top capture  105  and a bottom capture  106 . The top capture  105  or the bottom capture  106  may be a rivet, a snap, an adhesive, hooks and loops, a zipper, or any like fastener known to those skilled in the art. In one embodiment, the top capture  105  or bottom capture  106  may be constructed from fabric that is secured to the pack  104  on the left side and the right side of the flexible support member  101  and retains the flexible support member  101  against the pack  104 . The fabric may be constructed from cotton, nylon, polyester, polyethylene, or the like. In another embodiment, the top capture  105  or bottom capture  106  may be constructed from fabric that is secured to the pack  104  on the left side and the right side of the flexible support member  101  as well as above the top end  102  for a top capture  105  and below the bottom end  103  for a bottom capture  106 . 
         [0028]      FIG. 2   a  depicts one embodiment of a top capture  205  in which the flexible support member  201  is secured to the pack  204  by a piece of fabric  211  which is connected to the pack  204  by stitches  212  on either side of the flexible support member  201 .  FIG. 2   b  depicts an embodiment of the top capture  205  in which the flexible support member  201  is secured to the pack  204  by a piece of fabric  211  which is connected to the pack  204  by stitches  212  on either side of the flexible support member  201  and also above the flexible support member  201 . 
         [0029]    The top capture  105  or bottom capture  106  may removably connect the flexible support member  101  to the pack. This may be achieved by connection methods including, but not limited to, hooks and loops, snaps, rivets, buttons, zippers, pockets, or the like. In the embodiment depicted in  FIGS. 3   a  and  3   b , the flexible support member  201  may be removed from or inserted into the pocket formed by the connection of the fabric  211  to the pack  204 . 
         [0030]    Returning to  FIG. 1 , the pack  104  may be any backpack, duffel, purse, case, sack, or the like known in the art. In one embodiment of the inventive concept, the pack  104  may be a backpack with multiple pockets, straps, or other securing means for containing equipment. The backpack may have two shoulder straps that are worn across the wearer&#39;s shoulders. Each shoulder strap may connect to a low point and a high point on the backpack. The backpack may also have a waist strap that is secured to the wearer&#39;s waist and distributes a significant amount of the weight of the backpack and contents to the wearer&#39;s torso. 
         [0031]    A tensioner  108  may connect to two tensioner attachment points  107 . The tensioner  108  may be a rope-like structure constructed from a synthetic material that resists elongation when subject to tensile stress. Suitable materials for the tensioner  108  may include, but are not limited to, polyester, nylon, polyethylene, cotton, or the like. Materials with properties identical to or similar to brand name Dyneema® may be used to construct the tensioner  108 . The tensioner  108  may have a tension length that is measured as the length of tensioner  108  disposed between the two tensioner attachment points  107  to which the tensioner  108  is connected. 
         [0032]    A tensioner attachment point  107  may be disposed on the pack  104 . The tensioner attachment point  107  may be disposed in close proximity to each top end  102  and each bottom end  103 . The tensioner attachment point  107  may connect to the pack  104  at the same location as the top capture  105  or bottom capture  106 . Two tensioner attachment points  107  may be disposed on the pack  104  for each flexible support member  101  that is present. 
         [0033]    The tensioner  108  may be connected to the pack  104  in such a way that adjusting the length of the tensioner  108  may exert stress on the flexible support member  101  and shortening the tensioner  108  may cause the flexible support member  101  to bow away from the pack wearer&#39;s body. When the flexible support members  101  are bowed, they may support the weight of the pack  104  and its contents away from the wearer&#39;s body. Lateral force may be applied to the flexible support member  101  to deflect the midsection of the flexible support member  101  before the tensioner  108  may be shortened. 
         [0034]    The tensioner length may be adjusted to manipulate the shape of the flexible support member  101  across which the tensioner  108  is disposed. When the tensioner length is at maximum length, which is any length longer than the length of the flexible support member  101  across which the tensioner  108  is disposed, the flexible support member  101  may maintain a substantially planar shape. When the tensioner length is adjusted to activating length, which is any length shorter than the length of the flexible support member  101  across which the tensioner  108  is disposed, the flexible support member  101  may be subject to forces that draw the top end  102  and the bottom end  103  closer together and cause the flexible support member  101  to assume an arcuate shape.  FIG. 3  depicts the pack on a wearer&#39;s back with the tensioners  108  at the activating length. 
         [0035]    The tensioner  108  may be connected to the tensioner attachment point  107  by threading the tensioner  108  through a first opening of an attachment apparatus and a second opening of an attachment apparatus. The tensioner  108  may pass through the first opening substantially 180° opposed to the direction at which it may pass through the second opening. The tensioner  108  may be secured in place by the attachment apparatus through friction, clamping, or the like. The tensioner length may be adjusted by pulling on either free end of the tensioner  108 . The force exerted by the attachment apparatus may be removed from the tensioner  108  to allow the tension length to increase. 
         [0036]      FIG. 4  depicts one embodiment of the tensioner attachment point  407  in more detail. The tensioner  408  is connected to the tensioner attachment point through an attachment apparatus  413 . The free end  414  of the tensioner  408  may be pulled to shorten the tension length. The attachment apparatus  413  may be adjusted to lengthen the tension length. Lateral stress may be applied to the flexible support member  401  to allow the flexible support member  401  to flex and provide the ability to shorten the tension length.  FIG. 4  depicts an embodiment of the tensioner attachment point  407  in proximity to the top capture  405 . Embodiments of the tensioner attachment point  407  in proximity to the bottom capture may be identical or similar to that shown in  FIG. 4 . 
         [0037]      FIG. 5   a  depicts the tensioners  508  adjusted to the activating length. When the tensioners  508  are at the activating length, the tension length is shorter than the length of the portion flexible support member  501  that is disposed between the two tensioner attachment points  507  that connect the tensioner  508  to the pack. The tension length may be shortened by pulling on the free end  514  of the tensioner  508 . Adjusting the tensioner  508  to the activating length, may cause the flexible support member  501  to bow away from the tensioner  508 . 
         [0038]      FIG. 5   b  depicts the tensioners  508  adjusted to the maximum length. When the tensioners  508  are at the maximum length, the tension length is longer than the length of the portion flexible support member  501  that is disposed between the two tensioner attachment points  507  that connect the tensioner to the pack. 
         [0039]    In one embodiment of the inventive backpack frame  100 , as depicted in  FIG. 1 , there may be two flexible support members  101 , two tensioners  108 , two top captures  105 , two bottom captures  105 , and four tensioner attachment points  107 . In such an embodiment, the tension length of each tensioner  108  may be adjusted independently. In some embodiments, the tension length of each tensioner  108  may be adjusted dependent on each other. 
         [0040]    In embodiments with two flexible support members  101 , they may be disposed substantially parallel to one another. The two flexible support members  101  may be substantially identical in length. The top captures  105  may be disposed at substantially the same height on the pack  104  and the bottom captures may be disposed at substantially the same height on the pack  104 . 
         [0041]    A cross-member  109  may extend between two or more flexible support members  101 . In embodiments utilizing a cross-member  109 , the cross-member  109  may connect substantially orthogonally to each flexible support member  101 . The cross-member  109  may be constructed from a material similar to that of the flexible support member  101 . However, it may not be necessary for the cross-member  109  to flex. The cross-member  109  may be resiliently flexible or rigid. In some embodiments of the inventive backpack frame  100 , a cross-member  109  may connect two flexible support members  101  at or near the top ends  102  while a second cross-member  109  may connect the two flexible support members  101  at or around their mid-points. The cross-member  109  may connect to the pack  104  and to the flexible support member  101  by attachment structures similar to the top capture  105  or bottom capture  106 . 
         [0042]      FIG. 2   c  depicts a cross-member capture  215 . In this embodiment of the cross-member capture  215 , the flexible support member  201  may be surrounded by the fabric  211 . Alternatively the fabric  211  may extend over the flexible support member  201  and be secured to the pack  204  by stitching along the side of the flexible support member  201  that is opposed to the side of the flexible support member  201  that is adjacent to the cross-member  209 . The fabric  211  may be secured to the pack  204  with stitches  212  along either side of the cross-member  209 . 
         [0043]    A mesh structure  110  may extend substantially between two or more tensioners  108 . The mesh structure  110  may be substantially planar and provide a breathable surface to come into contact with a wearer&#39;s back when the backpack is in use. The mesh structure  110  may extend less than the entire length of the tensioner  108  and may be less than the shortest possible activating length. The mesh structure  110  may be removably attached to the tensioners  108 . The mesh structure  110  may be an area of mesh, lightweight, or breathable fabric disposed between the tensioners  108 . 
         [0044]    The foregoing examples have been provided in the interest of clarity to illustrate an embodiment of the present invention in substantial detail. A person of skill in the art will appreciate that one or more of the above provided embodiments may be included in the use of the backpack frame of the present invention. Additionally, a person of skill in the art will appreciate additional embodiments that would be included within the scope and spirit of the present invention, after having the benefit of this disclosure. Furthermore, a skilled artisan will appreciate that the operations described above, along with additional operations that would be apparent to those in the art, may be performed exclusively, incrementally, sequentially, simultaneously, or any other operative configuration. 
         [0045]    Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims.