Patent Publication Number: US-2013240590-A1

Title: Ultralight Backpack

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
     Not applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX  
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     People have used backpacks of various types for carrying loads on their backs for many years. Two basic types of packs are known from the prior art; rucksacks, with or without internal frames, and external frame packs. Patents and advertising disclose hundreds of variations on these two themes. 
     Rucksacks essentially consist of a bag with shoulder straps. They are known from ancient times. The disadvantage of rucksacks without frames is that they sag and sway under heavier loads. In modern times this problem has been addressed by the addition of hip belts and internal frames. The addition of frames has greatly reduced movement of the load, but has required the addition of padding to protect the back of the wearer. These additions have significantly increased the weight of rucksacks. Modern internal frame packs are essentially rucksacks with padded frames and hip-belts. They are comfortable to carry, but heavy. 
     External frame packs essentially consist of a rigid frame having a pair of upright side rails and two or more vertically spaced arched cross-members. One or more tensioned cloth back support bands are mounted between the side rails to hold the frame away from the bearer&#39;s back. The load is either lashed to the frame or stored in a bag attached to the frame. Originally the frames consisted of wood and steel, which made them quite heavy. As modern materials, particularly aluminum, have become available these packs have become lighter. Hip-belts have been added as well, reducing shoulder fatigue. External frame packs have proven to be useful for carrying heavy loads, but suffer from the disadvantage that they are wide and bulky. They also increase fatigue by carrying the load away from the bearer&#39;s body, thereby altering the body&#39;s natural balance. 
     My invention overcomes all of these disadvantages by providing a plurality of strong, light vertical support members held as close as practicable to the bearer&#39;s body, separated only by a removable pad of a type which the bearer will normally carry for other uses, such as a backpacker&#39;s sleeping pad. 
     A number of backpacks exist wherein the padding for the pack has been adapted for use in an auxiliary manner, as for seat cushioning or sleeping upon. However, the prior art discloses no backpack designed to use a variety of types of padding normally carried by backpackers for other camping purposes, such as backpacker&#39;s sleeping pads, as part of the backpack, itself. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention provides an extremely light and comfortable backpack for carrying a load upon the back of the bearer. This is accomplished by minimizing the number and weight of the elements of the backpack and providing a means of incorporating a variety of types of removable padding, of a sort normally carried for other camping uses, into the backpack, thus avoiding the need for extra padding or other means of protecting the bearer&#39;s back from the load. This reduces the total weight of the load and holds it as close as practicable to the bearer&#39;s center of gravity. 
     An embodiment of the invention consists of a sheath for insertion of a removable pad, to the posterior portion of which are affixed two or more vertical support members to which the load is attached. Shoulder straps are attached to the top and bottom of the sheath or the vertical support members, and a hip belt is attached to the vertical support members or the sheath. 
     The sheath is made of a durable lightweight fabric such as nylon and is approximately rectangular in shape. It is of a size and shape to conveniently fit the bearer&#39;s back and suitable to hold a variety of removable pads, including folded backpacker&#39;s sleeping pads of different types. The vertical support members to which the load is attached are made of durable, lightweight material which is rigid but flexible, such as carbon fiber or fiberglass. A bag or bags may be attached to the vertical support members for convenient storage of the load. The shoulder straps and hip belt are made of durable lightweight material and are appropriately padded for the comfort of the bearer. 
     This backpack is extremely simple, consisting of a sheath or similar means of containment for padding which will be carried by the bearer for other uses, a plurality of lightweight vertical support members, shoulder straps and a hip belt. It requires no additional straps, stays, horizontal structural members, tensioning devices or the like, thereby reducing weight to a minimum. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is a perspective view of the backpack, constructed in accordance with the present invention. It is shown with a load attached, worn by a backpacker. 
         FIG. 2  is a perspective view of the anterior side of the backpack, showing the hip belt and shoulder straps in working configuration. 
         FIG. 3  is a perspective view of the posterior side of the backpack, showing the hip belt encircling the backpack and the means of attachment of the vertical support members and shoulder straps to the sheath. 
         FIG. 4  is a partial view, being an elevation view of the anterior side of the hip belt strap, showing the means by which the hip belt is attached to each of the vertical support members. 
         FIG. 5  is a partial view, being a perspective view of the sheath and vertical support members without the shoulder straps or hip belt, showing the sheath flap open and the removable pad inside the sheath. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to  FIGS. 1 through 5  of the drawings, a preferred embodiment of the present invention is shown. Backpack  10  comprises a sheath  11  for insertion of a removable pad  24 , typically a backpacker&#39;s sleeping pad, which is held in place and protected by sheath flap  11   a . To the posterior portion of the sheath  11  are attached vertical support members  14  by means of vertical support member retaining tabs  12  at the top and middle, and vertical support member pockets  13  at the bottom. Load items  26  are attached to vertical support members  14 . Shoulder strap upper parts  15 , to which are affixed shoulder pads  16 , are attached to the top of the sheath  11 , and held securely there by means of shoulder strap reinforcement gussets  19 . Shoulder strap lower parts  17  are attached to the bottom of the sheath  11 . Shoulder strap upper parts  15  and shoulder strap lower parts  17  are connected by shoulder strap buckles  18 . Hip belt strap  20 , to which are affixed hip belt pads  22 , is attached to the vertical support members  14  by means of hip belt to vertical support member retaining tabs  21 . Alternatively, hip belt strap  20  may be sewn or otherwise affixed to the sheath  11 . The two ends of hip belt strap  20  are fastened around the waist of backpacker  25  by means of hip belt buckle  23 . 
     The sheath  11  is made of a durable lightweight fabric such as nylon. It is approximately rectangular in shape. It is of a size to conveniently fit the back of the backpacker  25  and suitable to hold a removable pad  24 , typically a folded backpacker&#39;s sleeping pad. Typically the sheath  11  will be approximately  18  inches in width, 22 inches in height, and 2 inches in depth, though these dimensions may vary according to the size and shape of the desired removable pad  24 , and the dimensions of the backpacker  25 . The sheath  11  is shown in  FIGS. 1 ,  2 ,  3  and  5  in the shape it assumes when the removable pad  24  is inside of it. Without the removable pad  24  inside, the sheath  11  is flaccid. 
     As shown in  FIG. 3 , the vertical support members  14  are attached to the posterior side of the sheath  11  at the top and middle by means of vertical support member retaining tabs  12 . The lower ends of the vertical support members  14  are inserted into the vertical support member pockets  13  at the bottom of the sheath  11 . As shown in  FIG. 4 , the hip belt strap  20  is attached to the vertical support members  14  by means of hip belt to vertical support member retaining tabs  21 , being free to slide along the vertical support members  14 . 
     The vertical support members  14  are made of a durable, lightweight material which is rigid but flexible, such as fiberglass or carbon fiber. Typically these will be elongated, cylindrical rods between one-eighth and one-half inch in diameter. Some variation in diameter is possible, depending on the nature of the materials to be used. Non-cylindrical vertical support members  14  may be used, as well. The vertical support members  14  are shown mounted separately from each other. Alternatively, they may be connected by means of horizontal or diagonal cross-members, thereby creating a frame. Another alternative is that they may be constructed of a single piece of flexible material, bent into a u-shape and attached as described above. 
     The height of the vertical support members  14  may vary according to the load to be carried, but will typically be several inches taller than the sheath  11 . The vertical support members  14  will be spaced equidistant from and parallel to the vertical center line of the sheath  11  and spaced apart a suitable distance for securing the load. These dimensions may vary according to the nature of the loads to be attached and the dimensions of the bearer. Extensions of various sorts may be attached to the vertical support members  14  to increase the effective height or width of the load attachment area. 
     The shoulder strap upper parts  15  are attached to the posterior side of the sheath  11  and reinforced by the shoulder strap reinforcement gussets  19  as shown in  FIG. 3 . The shoulder strap upper parts  15  extend over the top of the sheath  11  and help to keep the removable pad  24  and the sheath flap  11   a  in place.  FIG. 5  shows the removable pad  24  and the sheath flap  11   a  in detail, absent the various shoulder strap and hip belt parts. The shoulder strap upper parts  15  are connected to the shoulder strap lower parts  17  in front of the backpack  10  by shoulder strap buckles  18 , as shown in  FIG. 2 . They are worn over the shoulders of backpacker  25  as shown in  FIG. 1 . The shoulder strap upper parts  15  and shoulder strap lower parts  17  are made of durable lightweight material such as nylon webbing or the like. Shoulder pads  16  are affixed to the upper shoulder strap parts  15  in such a position and manner as to cushion the weight on the shoulders of backpacker  25 . Alternatively, the shoulder strap upper parts  15  and/or shoulder strap lower parts  17  may be attached to the vertical support members  14 . 
     The hip belt strap  20  encircles the sheath  11 , the vertical support members  14  and the waist of the backpacker  25 . It is fastened in front of the waist of backpacker  25  by means of hip belt buckle  23 , serving to hold the sheath  11  firmly against the back of the backpacker  25  and to support the weight of the load on the hips of the backpacker  25 . Hip belt pads  22  are affixed to the hip belt strap  20  in such a position and manner as to cushion the weight of the load on the hips of the backpacker  25 . 
     The hip belt  20  is made of durable lightweight material such as nylon webbing or the like. The hip belt  20  is typically made of a single strap, attached to each of the vertical support members  14  by hip belt to vertical support member retaining tabs  21 , as shown in  FIG. 4 , being free to slide up and down the vertical support members  14 . Alternatively, the hip belt  20  may be sewn or otherwise attached to the sheath  11 . Another alternative is that the hip belt  20  may be constructed in two parts, each part being attached either to a vertical support member  14  or sewn or otherwise attached to the sheath  11 . Also, the backpack  10  may be constructed without a hip belt  20 . 
     The description above and the accompanying drawings should be interpreted as illustrative, only. Modifications to the preferred embodiment or embodiments disclosed above may be made without departing from the scope of the invention. For example, the means of attachment of the load to the backpack  10  may vary greatly in accordance with the invention, such as attaching a bag or other container directly to the sheath  11 .