Abstract:
An exemplary packing case ( 10 ) for substrates includes a main body ( 12 ), at least one buffer ( 14 ) and a cover ( 11 ). The cover is configured for attaching onto the main body. The main body includes a bottom plate ( 121 ) and a plurality of side walls ( 122 ) substantially perpendicularly extending from the bottom plate. The bottom plate and the side walls form an accommodating space. An inner surface of at least one of the side walls includes a plurality of first latching members. The at least one first buffer includes a plurality of second latching members. The second latching members and the first latching members of the at least one side wall have complementary shapes such that the at least one first buffer is detachably engagable with the at least one side wall thereby adjusting a capacity of the accommodating space.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to packing cases for containing frangible substrates, and more particularly to a packing case having buffers for holding glass substrates of display devices such as liquid crystal panels. 
       GENERAL BACKGROUND 
       [0002]    The liquid crystal display (LCD) has been widely used in various electronic equipment. Glass substrates are very important components of LCDs. The two main glass substrates of a typical LCD are a color filter substrate and a thin film transistor substrate. Once the separate glass substrates have been fabricated in mass production of LCDs, the glass substrates must be properly protected during transportation to the next manufacturing stage. Therefore special packing cases with low compression deformation, high impact resistance, and high dimensional stability are needed. 
         [0003]      FIG. 4  is an exploded, isometric view of a typical packing case for containing glass substrates of liquid crystal displays. The packing case  40  is made from polyolefin foam. The packing case  40  includes a cover  41  and a main body  42 . The cover  41  and the main body  42  cooperatively form a space to accommodate glass substrates  431 . The main body  42  includes a bottom plate  421 , and four first side walls  422  perpendicularly extending from four side edges of the bottom plate  421 . The first side walls  422  are connected end to end. Top ends of the first side walls  422  cooperatively define a peripheral first step structure  423 . 
         [0004]    The cover  41  includes a top plate  411 , and four second side walls  412  perpendicularly extending from the top plate  411 . The second side walls  412  are connected end to end. Bottom ends of the second side walls  412  cooperatively define a peripheral second step structure (not labeled) corresponding to the first step structure  423 . 
         [0005]    The glass substrates  431  are arranged one on top of the other, and every two adjacent glass substrates  431  are spaced by a spacing sheet  432 . The glass substrates  431  and the spacing sheets  432  form a stack  43 . When loading the glass substrates  431  into the packing case  40 , the stack  43  is arranged on the bottom plate  421  of the main body  42 , and peripheral edges of the stack  43  abut inner surfaces of the first side walls  422  and the second side walls  412 . The cover  41  is attached on the main body  42 . The cover  41  is fixed to the main body  42  by the fitting engagement of the first step structure  423  with the second step structure. Thus, the glass substrates  431  are loaded into the packing case  40 . 
         [0006]    However, the packing case  40  is only suitable for transporting glass substrates  431  having a certain size. Different packing cases are needed to transport glass substrates having other sizes. Thus, the cost of transporting differently sized glass substrates is correspondingly increased. 
         [0007]    What is needed, therefore, is a packing case that can overcome the above-described deficiencies. 
       SUMMARY 
       [0008]    In one preferred embodiment, a packing case for substrates includes a main body, at least one buffer and a cover. The cover is configured for attaching onto the main body. The main body includes a bottom plate and a plurality of side walls substantially perpendicularly extending from the bottom plate. The bottom plate and the side walls form an accommodating space. An inner surface of at least one of the side walls includes a plurality of first latching members. The at least one first buffer includes a plurality of second latching members. The second latching members and the first latching members of the at least one side wall have complementary shapes such that the at least one first buffer is detachably engagable with the at least one side wall thereby adjusting a capacity of the accommodating space. 
         [0009]    Other novel features, advantages and aspects will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is an exploded, isometric view of a packing case according to a first embodiment of the present invention, also showing two glass substrates and a spacing sheet. 
           [0011]      FIG. 2  is an assembled view of the packing case of  FIG. 1 . 
           [0012]      FIG. 3  is an exploded, isometric view of a packing case according to a second embodiment of the present invention, also showing two glass substrates and a spacing sheet. 
           [0013]      FIG. 4  is an exploded, isometric view of a conventional packing case, also showing two glass substrates and a spacing sheet. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0014]    Reference will now be made to the drawings to describe the preferred embodiments in detail. 
         [0015]    Referring to  FIG. 1 , a packing case  10  according to a first embodiment of the present invention is shown. The packing case  10  includes a cover  11 , a main body  12 , and two buffers  14 . The main body  12  and the cover  11  corperatively form a space to accommodate glass substrates  131 . The buffers  14  are used to adjust a capacity of the packing case  10 . 
         [0016]    The main body  12  includes a bottom plate  121 , and four first side walls  122  perpendicularly extending from four side edges of the bottom plate  121 . The four first side walls  122  are connected end to end. Top ends of the first side walls  122  cooperatively define a peripheral first step structure  124 . 
         [0017]    An inner side of each of the first side walls  122  includes a plurality of first protrusions  123  extending therefrom. Each first protrusion  123  is isosceles trapezoid-shaped, and includes a first surface  1231  and two opposite second surfaces  1232 . The second surfaces  1232  are equal to each other in size, and are obliquely connected to the first surface  1231 . Every two adjacent first protrusions  123  define a first gap  126  therebetween. The first gap  126  is accordingly isosceles trapezoid-shaped. 
         [0018]    Each buffer  14  has a first side surface  141 , and a second side surface  142  opposite to the first side surface  141 . The first surface  141  is flat. The second side surface  142  includes a plurality of second protrusions  143  extending therefrom. Each of the second protrusions  143  is isosceles trapezoid-shaped, and has substantially the same shape and size as each first gap  126  of the main body  12 . Every two adjacent second protrusions  143  define a second gap  146  therebetween. The second gap  146  is accordingly isosceles trapezoid-shaped. A shape and size of each second gap  146  is substantially the same as a shape and size of each first protrusion  123  of the main body  12 . 
         [0019]    The packing case  10  is made from a foam resin having a foaming ratio of 3-30, such as an olefinic resin foam. The olefinic resin foam can be an ethylene series polymer foam such as low density polyethylene foam, high density polyethylene foam, ethylene-vinyl acetate copolymer foam, ionomer foam, olefinic polymer blend foam, polypropylene foam, and so on. 
         [0020]    The cover  11  includes a top plate  111  and four second side walls  112  perpendicularly extending from side edges of the top plate  111 . The second side walls  112  are connected end to end. Bottom ends of the second side walls  112  cooperatively define a peripheral second step structure (not labeled), corresponding to the first step structure  124  of the main body  12 . The cover  11  is fixed to the main body  12  by fitting engagement of the first step structure  124  with the second step structure. 
         [0021]    The glass substrates  131  are stacked one on top of the other. Every two adjacent glass substrates  131  are spaced by a spacing sheet  132 . Thus, the glass substrates  131  and the spacing sheets  132  form a stack  130 . When loading the glass substrates  131 , the stack  130  is arranged on the bottom plate  121  of the main body  12 . Peripheral edges of the stack  130  abut the inner sides of the first side walls  122 , thus the glass substrates  131  are prevented from sliding. Then, the cover  11  is attached on the main body  12 . Thus, the glass substrates  131  are loaded into the packing case  10 . 
         [0022]    Referring also to  FIG. 2 , when loading another set of glass substrates (not shown) having a smaller size, the glass substrates and spacing sheets (not shown) are stacked to form a new smaller stack (not shown). For example, the smaller stack may be shorter in length than the stack  130 , but have the same width as the stack  130 . The two buffers  14  shown are disposed in the main body  12 , with the second protrusions  143  of the buffers  14  being inserted into and engaged in the first gaps  126  of the two short first side walls  122  respectively. Thereby, the first protrusions  123  of the short first side walls  122  are simultaneously inserted into and engaged in the second gaps  146  of the buffers  14 . Thus, the buffers  14  are securely fixed to the main body  12 , and a capacity of the main body  12  is reduced to fit the size of the smaller stack. The smaller stack is arranged on the bottom plate  121  of the main body  12 . Peripheral edges of the smaller stack abut the inner sides of the two long first side walls  122  and the first surfaces  141  of the buffers  14 . Thus the glass substrates are prevented from sliding. The cover  11  is attached on the main body  12 . Thus, the glass substrates are loaded into the packing case  10 . 
         [0023]    In another example, the packing case  10  can include two more buffers  14 . The two additional buffers  14  can be fixed to the two long first side walls  122  of the main body  12 , according to the size of an even smaller stack (not shown) of glass substrates. In still another example, the packing case  10  can include a total of three buffers  14 . 
         [0024]    Unlike conventional packing cases, the packing case  10  includes the main body  12  with the first side walls  122 . The inner sides of the first side walls  122  include a plurality of first latching members in the form of the first protrusions  123 . The buffers  14  have a plurality of second latching members in the form of the second protrusions  143 . The buffers  14  can be selectively and detachably engaged with the main body  12 , by the engagement of the first latching members with the second latching members. Thus, a capacity of the packing case  10  is adjustable. Glass substrates having different sizes can be packed in the packing case  10 . The peripheral edges of a stack of the glass substrates abut selected of the inner sides of the first side walls  122  of the main body  12  and/or selected of the buffers  14 . Thus, the glass substrates are packed properly and tightly. No other different packing cases are needed. Therefore, the cost of transporting differently sized glass substrates is reduced. 
         [0025]    Referring to  FIG. 3 , a packing case  20  according to a second embodiment of the present invention is similar to the packing case  10 . However, the packing case  20  includes two first buffers  25  and two second buffers  26 . The second buffers  26  are substantially the same as the buffers  14  of the packing case  10 . Each second buffer  26  includes a first surface  261  and a second surface  262  at opposite sides thereof. The first surface  261  has a plurality of first gaps  266  defined thereat, and the second surface  262  is smooth. 
         [0026]    The first buffers  25  are similar to the buffers  14  of the packing case  10 . Each first buffer  25  includes a third surface  251  and a fourth surface  252 . The third surface  251  has a plurality of second gaps  256  defined thereat. A shape and size of each second gap  256  is substantially the same as a shape and size of each of first protrusions  223  of a main body  22 . 
         [0027]    The fourth surface  252  has a plurality of second protrusions  253  extending therefrom. A shape and size of each second protrusion  253  is substantially the same as a shape and size of each first gap  266 . 
         [0028]    When loading glass substrates (not labeled) having a smaller size, the glass substrates and spacing sheets (not labeled) are arranged to form a stack  23 . For example, the stack  23  may be shorter in length than a corresponding length of the main body  22 . The first protrusions  223  of the main body  22  are received in the second gaps  256  of the two first buffers  25  shown. Thus, the first buffers  25  are fixed to the main body  22 . The second protrusions  253  of the first buffers  25  are received in the first gaps  266  of the two second buffers  26  shown. Thus, the second buffers  26  are fixed to the first buffers  25 . Accordingly, a capacity of the packing case  20  is reduced to fit the size of the stack  23 . The stack  23  is arranged on a bottom plate (not labeled) of the main body  22 . Peripheral edges of the stack  23  abut inner sides of long side walls of the main body  22  and the second surfaces  262  of the second buffers  26 . 
         [0029]    In another example, the packing case  20  can include two more first buffers  25  to further reduce the capacity thereof. The additional first buffers  25  are fixed to the long side walls of the main body  22 , according to the size of an even smaller stack (not shown) of glass substrates. In still another example, the packing case  20  can include two more second buffers  26  to even further reduce the capacity thereof. The additional second buffers  26  are fixed to the two first buffers  25  at the two long side walls of the main body  22 . 
         [0030]    It is to be further understood that even though numerous characteristics and advantages of various embodiments have been set out in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.