Abstract:
A bag of the present invention includes a first side fabric, a second side fabric, and two lateral fabrics connected to each other to form the bag with a room therein and an opening at a top thereof. The first side fabric has a first length, which is longer than a second length of the second side fabric. The bag provides various means for closing and opening the opening of the bag and when the opening is open, the second side fabric will fall outward until the lateral fabrics are bound tight to get a bigger space for storing goods.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to a bag for storage, and more particularly to a bag of a changeable size thereof. 
         [0003]    2. Description of the Related Art 
         [0004]    Typically, a bag, such as handbag or backpack, has a room therein to store goods. A conventional bag usually has a fixed room to store goods with size equal to or smaller than the space. In other words, a conventional bag is unable to store goods of a size greater than its fixed space. Moreover, even when the bag doesn&#39;t store any goods therein, it will still take room and cause a waste of space. 
         [0005]    Some backpacks have pockets on lateral sides to receive goods that user may need frequently, such as water bottle. Such pocket is made by stitching flexible fabric on the backpack. The fabric is attached on the backpack when there is nothing received therein. However, such pocket has limited capacity of storing goods and may not safely keep the goods therein. Some pockets are made by stitching canvas on the backpack with a zip to close an opening thereof. A drawback of such pocket is that its size cannot be expanded. 
       SUMMARY OF THE INVENTION 
       [0006]    The primary objective of the present invention is to provide a bag of a changeable size to store goods of various sizes therein. 
         [0007]    The secondary objective of the present invention is to provide a bag of a changeable size, which stores goods therein safely. 
         [0008]    According to the objectives of the present invention, a bag of the present invention includes a first side fabric, a second side fabric, and two lateral fabrics connected to each other to form a bag with a room therein and an opening at a top thereof. The first side fabric is longer than the second side fabric that when the opening is open the bag will have a bigger size, and the bag will has a smaller size when the opening is close. 
         [0009]    In an embodiment, the second side fabric has an extended portion, which is substantially perpendicular to the first side fabric, to form a bottom of the bag and a front shade portion, which is substantially perpendicular to the extended portion, to form a front side of the bag. 
         [0010]    In an embodiment, the bag is provided with a zip between the first side fabric and the second side fabric to open and close the opening. 
         [0011]    In an embodiment, the bag is provided with a cord and a fastener. The cord passes through the second side fabric, go around the first side fabric, and then back through the second side fabric that the cord has two sections left in the room of the bag. The fastener fastens the cord left out of the bag. The cord and the fastener may help in fastening the opening more firmly and keeping goods in more securely. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is an expanded aspect of the bag of a preferred embodiment of the present invention; 
           [0013]      FIG. 2  is a perspective view of the preferred embodiment of the present invention, showing the closed bag; 
           [0014]      FIG. 3  follows  FIG. 2 , showing the bag opening; 
           [0015]      FIG. 4  follows  FIG. 3 , showing the opened bag; 
           [0016]      FIG. 5(A)  to  FIG. 5(C)  are other views of  FIG. 2  to  FIG. 4  respectively; 
           [0017]      FIG. 6  is similar to  FIG. 2 , showing the bag with an extra pocket; 
           [0018]      FIG. 7  is a perspective view of the present invention, showing that the bag of the present invention is an independent item; 
           [0019]      FIG. 8  is similar to  FIG. 5(B) , showing that several pairs of Velcro belts are provided to close the opening; and 
           [0020]      FIG. 9  is similar to  FIG. 8 , showing that several pairs of buckles are provided to close the opening. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]      FIG. 1  shows an expanded view of a bag  1  of the preferred embodiment of the present invention and  FIG. 2  is the perspective view thereof. The bag  1  is made of flexible and soft fabrics including a first side fabric  10 , a second side fabric  20 , a first lateral fabric  30  and a second lateral fabric  40 . These fabrics are stitched together to form the bag  1  with a room  1   a  therein. As shown in  FIG. 1 , the first side fabric  10  is a rectangular fabric having a top side  12 , a bottom side  14 , and first and second long sides  16 ,  18 . The second side fabric  20  is a rectangular fabric also having a top side  22 , a bottom side  24 , and first and second long sides  26 ,  28 . The bottom side  24  of the second side fabric  20  and the bottom side  14  of the first side fabric  10  are stitched together. The first lateral fabric  30  has two lateral sides  32 ,  34  stitched to the first long side  16  of the first side fabric  10  and the second long side  28  of the second side fabric  20  respectively. The second lateral fabric  40  has two lateral sides  42 ,  44  stitched to the second long side  18  of the first side fabric  10  and the first long side  26  of the second side fabric  20  respectively. Consequently, the bag  1  has a room  1   a  therein and an opening  1   b  at a top thereof. 
         [0022]    The first side fabric  10  has a first length L 1  from the top side  12  to the bottom side  14 , and the second side fabric  20  has a second length L 2  from the top side  22  to the bottom side  24 . The second length L 2  is greater than the first length L 1 . As shown in  FIG. 1 , the second fabric  20  is divided into two portions, an expanded portion  20   a  and a front shade portion  20   b , wherein the expanded portion  20   a  is adjacent to the bottom side  24  and the front shade portion  20   b  is adjacent to the top side  22 , and the front shade portion  20   b  has a length and an area greater than that of the expanded portion  20   a . As shown in  FIG. 3  and  FIG. 4 , the frond shade portion  20   b  of the second side fabric  20  is stitched to the first and second lateral fabrics  30  and  40  respectively. 
         [0023]    The bag  1  of the preferred embodiment of the present invention is provided with a zip  50  to close the opening  1   b  thereof. The zip  50  has two chain strips  52  stitched to the top sides  12 ,  22 , the first long sides  16 ,  26 , and the second long sides  18 ,  28  of the first and second side fabrics  10 ,  20  respectively, two sliders  54 , and two cords  56  fastened to the sliders  54  respectively. User may hold the cord  56  to move the slider  52  along the chain strips  52  between a start point P 1  and a stop point P 2 . In the present embodiment, the stop point P 2  is at a middle of the chain strips  52 . When both of the sliders  54  are drawn to the stop point P 2 , as shown in  FIG. 2 , the opening  1   b  of the bag  1  is close, and when the sliders  54  are drawn to the start points P 1  respectively, as shown in  FIG. 3 , the opening  1   b  of the bag  1  is open, as shown in  FIG. 4 . We define a first condition indicating that the bag  1  is open, and a second condition indicating that the bag  1  is close. 
         [0024]    As shown in  FIG. 5(A)  to  FIG. 5(C)  and  FIG. 2  to  FIG. 4 , the bag  1  under the first condition is shown in  FIG. 5(A)  in which the second side fabric  20  is naturally curved outward to form a small room therein. It is because that the long sides  16 ,  26  of the first and the second side fabrics  10 ,  20  are connected together by the zip  50  and the length L 2  of the second fabric  20  is greater than the length L 1  of the first fabric  10 . Next, as shown in  FIG. 5(B) , as user draw the sliders  54  to make the top sides  12 ,  22  separate, the bag  1  is open and the second fabric  20  moves outward and downward because of gravity, and then the bag  1  is totally open when the sliders  54  are drawn to the start points P 1 , as shown in  FIG. 5(C) . At this moment, the bag  1  is under the second condition, and the expanded portion  20   a  forms a bottom of the bag  1 , the front shade portion forms a front side of the bag  1 , and the first and second lateral fabrics  30 ,  40  form the lateral sides of the bag  1 . Under this condition, the bag  1  has a greater room therein, and the room is open at a top thereof. In other words, the bag  1  of the present invention has a greater room with a wide opening when it is opened to receive goods with greater sizes, and when the bag  1  is closed the size of the room is reduced to hold the goods received therein. 
         [0025]    The bag  1  of the present invention is provided with a cord  60  and a fastener  62  as shown in  FIG. 4 . The cord  60  passes through an opening of the first side fabric  10  and through two rings (not shown) fixed at the second side fabric  20 , and then back through the opening of the first side fabric  10  again so that the cord  60  has two parallel sections left in the room of the bag  1 . The fastener  62  is mounted at the cord  60  left out of the bag  1 . When a goods, which is longer than the bag  1  of the present invention, is put in the bag  1 , it will be partially left out of the bag  1  and the opening  1   b  of the bag  1  cannot be closed. Under this condition, user may put such goods between the sections of the cord  60 , and pull the cord  60  to fasten the goods. In other words, the cord  60  is provided to fasten the goods received in the bag  1  when the opening  1   b  of the bag  1  cannot be closed. 
         [0026]    In order to carry more goods, the bag  1  of the present invention is provided with several flexible belts  64  on the second side fabric  20 , as shown in  FIG. 4 , or it may provide a pocket  66 , as shown in  FIG. 6 , or an inner pocket  68  on an inner side of the first side fabric  10 , as shown in  FIG. 5(C) . 
         [0027]    In the preferred embodiment described above, the first fabric  10  is an external part of a backpack  100 . In other words, the bag  1  of the present invention is an attached bag of the backpack  100 , and practically speaking, the bag  1  of the present invention may be an independent item, as shown in  FIG. 7 . 
         [0028]    For closing and opening the opening  1   b  of the bag  1  of the present invention, the bag  1  may provide several pairs of Velcro belts  70 ,  72  on the first and second side fabrics  10 ,  20  respectively, as shown in  FIG. 8 , or it may provide several pairs of buckles  74 ,  76 , as shown in  FIG. 9 . It should be marked that there are many means for closing and opening the bag, and they should be the equivalents of the present invention. 
         [0029]    In conclusion, the present invention provides a bag with an expandable size to store goods with various sizes that the goods may be held firmly in the bag of the present invention. The description above is a few preferred embodiments of the present invention and the equivalence of the present invention is still in the scope of the claim of the present invention.