Patent Publication Number: US-2011049000-A1

Title: Package structure for thin display apparatus and method of packing thin display apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims the benefit of priority from the prior Japanese Patent Application No. 2009-197914 filed on Aug. 28, 2009, the entire contents of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to a package structure for a thin display apparatus and a method of packing a thin display apparatus. 
     There are known package structures for use in shipping thin display panels such as liquid crystal panels and organic EL panels, and also thin display apparatuses equipped with such a thin display panel. Examples of known package structures are a common package structure with buffer members provided at four corners of an article to be packed for supporting the article and an improved package structure for a thin display apparatus disclosed in Japanese Un-Examined Patent Application Publication No. 2006-232360 (referred to as Document 1, hereinafter). 
     Document 1 discloses a package structure for use in packing a liquid crystal television in a corrugated cardboard box with holding members to be in contact with both ends of the television at the bottom and top sides thereof. The package structure features a reinforced plate that is turned around the television in the vertical direction to wrap the television, with a sponge plate attached to the reinforced plate to precompress the center region of a display panel in the lateral direction. 
     According to the package structure in Document 1, the sponge plate minimizes jolts of the center region of the display panel that are generated by shocks, vibration, etc., applied to the television while being shipped. Thus, a thin display apparatus, such as a liquid crystal television, can withstand shocks, vibration, etc., generated during shipping even if a display panel is relatively large. 
     However, there is a strong demand for lighter-weight and thinner display panels and apparatuses with a larger screen, for a variety of installation types such as hung on wall and ceiling. 
     Light weight display panels and apparatuses are achieved with light metals such as aluminum, in place of metals such as iron, for display panel frames that support a thin display panel and cabinets in which a thin display panel is installed. Such a light metal offers a light weight of around 6 kg which used to be 10 kg or so for thin display panels and apparatuses. 
     Such light weight display panels and apparatuses, however, have a tendency of low stiffness compared to heavy display panels and apparatuses of the same screen size. 
     Thin liquid crystal display panels are achieved with a thin cell panel, optical sheet, diffusion plate, and other thin components with a small distance between these components. The thinness of 10 mm or less has been achieved for the thinnest part of display panels, which used to be 30 mm or more. 
     Such light-weight and thin display panels and apparatuses, however, suffer several problems when packed in a corrugated cardboard box and shipped. 
     A first problem is that a cell panel is damaged at the rear side due to rubbing or hitting each other between the cell panel and an optical sheet provided behind the panel when vibration is externally applied. 
     This problem is caused by a thinner structure with a smaller distance between the cell panel and the optical sheet, in addition to that a thinner cell panel is more vibrated at the center region in back and forth when an external force is applied. 
     A second problem is that a package box is also made thinner. Thus, when the package box falls down a packed cell panel or display apparatus could suffer flexure deformation as protruding in the direction of falling down, at the center region of the top section of the cell panel or display apparatus. 
       FIG. 1  illustrates the second problem. An article  101  to be packed is a thin display panel, for example. Attached to the four corners of the article  101  are buffer members  102 . The article, or the thin display panel  101  is packed in a package box  103  (indicated by a dash-dot line for brevity) with the buffer members  102 . 
     Shown in (a) of  FIG. 1  is that the package box  103  is placed upright on a floor, etc. Shown in (b) of  FIG. 1  is that the package box  103  falls down in a direction indicated by an arrow. 
     When the package box  103  falls down in the direction indicated by the arrow, a flexurally-deformed portion K is created at the center region of the top side as protruding in the direction of falling down due to the shock of falling down, as shown in (b) of  FIG. 1 . 
     This problem is caused by that, although the display panel  101  is supported by the buffer members  102  at the four corners, the center region between the opposing corners is not protected by the buffer members  102 . The center region of the top side of the display panel  101  thus cannot withstand the shock of falling down, in addition to lower stiffness of the panel  101  that is made larger and thinner. 
     The first problem may be solved by the package structure disclosed in Document 1, with the sponge plate that precompress the center region of a display panel in the lateral direction to minimize vibration in back and forth. 
     Nevertheless, since the sponge plate is not provided at the center region of the top side of the display panel in Document 1, the second problem may not be solved by the package structure disclosed in Document 1. 
     Moreover, the package structure disclosed in Document 1 should be improved in the following points concerning a packing operation. 
     One point to be improved lies in the reinforced plate when an article to be packed is a thin display panel or apparatus of 10 mm or less in thickness. In detail, it seems that, if the reinforced plate is weakly turned around such a thin article, it cannot minimize vibration whereas, if it is strongly turned around, the sponge plate precompresses the display panel too much, which results in adverse effects to the thin display panel or apparatus with lowered stiffness. 
     Another point to be improved is that it takes time to turn the reinforced plate around an article to be packed and connect both ends of the reinforced plate, with several steps. 
     Still another point to be improved is that, when an article to be packed is mistakenly packed in a package box without the reinforced plate, the article has to be picked up from the package box for turning the reinforced plate around the article and then again packed in the package box, which leads to lower efficiency in packing operations. 
     SUMMARY OF THE INVENTION 
     A purpose of the present invention is to provide a package structure for a thin display apparatus and a method of packing a thin display apparatus, that offer easier packing operations and protect the packed display apparatus from being deformed when a package box falls down. 
     The present invention provides a package structure for packing a thin display apparatus having a display screen comprising: a reinforced plate to be attached to the display apparatus when the display apparatus is packed, the reinforced plate having an first end portion, a second end portion and a middle portion, the first end portion being positioned at a front side of the display apparatus, the second end portion being positioned at a rear side of the display apparatus and the middle portion being positioned at a top side of the display apparatus when the reinforced plate is attached to the display apparatus; a cushion member to be attached to a top portion of the display apparatus when the display apparatus is packed, the top portion being positioned at the top side; and a buffer member fixed to the first end portion of the reinforced plate, wherein, when the display apparatus is packed, the cushion member supports the top portion of the display apparatus from a front direction at the front side and from a rear direction at the rear side through the reinforced plate with the buffer member being in contact with the display screen or being positioned in the vicinity of the display screen at the front side. 
     Moreover, the present invention provides a method of packing a thin display apparatus having a display screen comprising the steps of: a first step of attaching a reinforced plate to the display apparatus, the reinforced plate having a first end portion, a second end portion, a middle bent portion and a buffer member that is fixed to the first end portion, the first and second end portions facing each other with the middle bent portion located between and connected to the first and second end portions, the reinforced plate being attached to the display apparatus so that the middle bent portion is set on a top portion of the display apparatus at a top side thereof, the buffer member is positioned at a front side of the display apparatus as facing the display screen and the second end portion is positioned at a rear side of the display apparatus; and a second step of attaching a cushion member to the reinforced plate so that the cushion member is set on the middle bent portion set, in the first step, on the top portion of the display apparatus. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  shows a view illustrating a problem of a known package structure; 
         FIG. 2  shows orthographic views of an exemplary article to be packed by a packing method according to an embodiment of the present invention; 
         FIG. 3  shows a first view illustrating the packing method according to the embodiment of the present invention; 
         FIG. 4  shows a second view illustrating the packing method according to the embodiment of the present invention; 
         FIG. 5  shows a third view illustrating the packing method according to the embodiment of the present invention; 
         FIG. 6  shows a development view of a main component of a package structure according to an embodiment of the present invention; 
         FIG. 7  shows a view of a folded state of the main component of the package structure according to the embodiment of the present invention, before used in the packing method according to the embodiment of the present invention; 
         FIG. 8  shows a transverse sectional view illustrating the package structure according to the embodiment of the present invention; 
         FIG. 9  shows a vertical sectional view illustrating the package structure according to the embodiment of the present invention; 
         FIG. 10  shows a partially enlarged view of  FIG. 9 ; 
         FIG. 11  shows an enlarged view of an area DT shown in  FIG. 10 ; 
         FIG. 12  shows a schematic view illustrating the dimension of the components of the package structure according to the embodiment of the present invention; and 
         FIG. 13  shows a perspective view of a modification to the package structure according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will be described with respect to  FIGS. 2 to 13 . 
       FIG. 2  shows orthographic views of an exemplary article to be packed by a packing method of the present invention. The exemplary article shown in  FIG. 2  is a thin display apparatus  50 , for example, a liquid crystal monitor. The signs “top”, “bottom”, “front”, “rear”, “left” and “right” are given to the drawings when necessary to indicate the direction with respect to the thin display apparatus  50 . 
     The thin display apparatus  50  includes a thin liquid crystal display panel  1  and a cabinet  2  for the display panel  1  to be installed, having an opening  2   a  through which a display screen  1   a  provided on a cell panel is of the display panel  1  is exposed. The cabinet  2  has a protruding portion  3  for installing a circuit board, etc., at the rear side. 
     The thin display apparatus  50  is a 32-inch liquid crystal monitor having 773 mm in width W, 496 mm in height H, 7 mm in thickness T 1  (except for the protruding portion  3 ), and 23 mm in thickness T 2  for the protruding portion  3 . 
     The thin display apparatus  50  (the liquid crystal monitor) has a mass of 5.7 Kg with the cabinet  2  made of aluminum (including the protruding portion  3 ). 
       FIGS. 3 to 5  show perspective views illustrating how to pack the thin display apparatus  50  in a package box, according to a packing method of the present invention. 
     Firstly, the thin display apparatus  50  is wrapped with a polyethylene film package (not shown). 
     Next, as shown in  FIG. 3 , corner cushions  4   a ,  4   b ,  4   c  and  4   d  are attached to the four corners of the cabinet  2 , as buffer members, so that the corner cushions  4   a  and  4   b , and  4   c  and  4   d  support the cabinet  2  at the bottom and top sides, respectively. 
     The polyethylene film package will not be referred to in the following description because it is much thinner than the other components and does not contribute to the advantages obtained by the present invention. 
     The corner cushions  4   a ,  4   b ,  4   c  and  4   d  are provided with slits  4   a   1 ,  4   b   1 ,  4   c   1  and  4   d   1 , respectively, having a specific shape and width so that the four corners of the cabinet  2  can be tightly inserted into the slits. Shown in  FIG. 3  are the slits  4   a   1 ,  4   b   1 , and  4   c   1 . The corner cushions  4   a ,  4   b ,  4   c  and  4   d  are made of styrene form. 
     Next, as shown in  FIG. 4 , a reinforced plate  5  bent into an almost J-shape is installed between the corner cushions  4   c  and  4   d  from the top side in a direction D 3  so that cabinet  2  is fit between the opposing inner surfaces of the J-shaped reinforced plate  5 . 
     The reinforced plate  5  is made of a corrugated cardboard, for example. When a corrugated cardboard is used, as shown in  FIG. 6 , a corrugated cardboard material is cut into a rectangular shape. Crease lines  5   a ,  5   b  and  5   c  are then made between one end portion  5   t   1  and another end portion  5   t   2  of the rectangular corrugated cardboard so that a valley fold is formed in a direction of the front side of a drawing paper of  FIG. 6 . The crease lines  5   a ,  5   b  and  5   c  are preferably made in a direction orthogonal to the direction of the flute. 
     Any flute type of corrugated cardboard can be used in the embodiment. Moreover, perforation may be made instead of the crease lines  5   a ,  5   b  and  5   c.    
     When the direction of the flute is set as indicated by an arrow in  FIG. 6 , a buffer plate  6  is fixed at the end portion  5   t   1  (in the direction of the flute) of the reinforced plate  5  (the upper side in  FIG. 6 ). 
     The buffer plate  6  is made of EPS (Expanded Polystyene), a type of styrene foam, sponge material, etc., and formed into a cuboid. The buffer plate  6  is fixed on the reinforced plate  5  by a fixing means, such as glue or an adhesive tape. The reinforced plate  5  has a width W 2  for an inner surface  5   e  that is the inner side when used, equal to or a little bit smaller than a width W 3  shown in  FIG. 3 . 
       FIG. 7  shows the reinforced plate  5  folded along the crease lines  5   a ,  5   b  and  5   c  when used in packing. 
     As shown in  FIG. 7 , the reinforced plate  5  is folded along the crease lines  5   a  and  5   b  at almost right angle whereas folded slightly along the crease line  5   c . Accordingly, the reinforced plate  5  is formed into an almost J-shape in cross section, having a bent portion kk. 
     The term “an almost J-shape” in this description includes not only a letter “J”-shape but also a π-shape with the end portion  5   t   2  located lower than that shown in  FIG. 7 . 
     The positions of the crease lines  5   a  and  5   b  of the reinforced plate  5  when folded are defined as follows: 
     A distance Dm 1  shown in  FIG. 7  is almost equal to H/2 shown in  FIG. 2  in which the reference sign H indicates the height of the thin display apparatus  50 . The distance Dm 1  is, as shown in  FIG. 7 , a distance between the position of the inner surface  5   e  between the crease lines  5   a  and  5   b  in a top-to-bottom direction and the center position of the buffer member  6  in the top-to-bottom direction. 
     A width T 3  of the inner surface  5   e  in a lateral direction (orthogonal to the top-to-bottom direction) shown in  FIG. 7  is equal to or little bit larger than thickness T 1  of the thin display apparatus  50  (except for the protruding portion  3 ) shown in  FIG. 2 . 
     The position of the crease line  5   c  will be discussed later. 
     In addition to the inner surface  5   e , the reinforced plate  5  has an inner surface  5   d  between the crease line  5   a  and the end portion  5   t   2 , an inner surface  5   f  between the crease lines  5   b  and  5   c , and an inner surface  5   g  between the crease line  5   c  and the end portion  5   t   1 , as shown in  FIGS. 6 and 7 . It is noted that the positions of the end portions  5   t   1  and  5   t   2  are upside down in  FIGS. 6 and 7 . 
     Referring again to  FIG. 4 , concerning the packing method of the present invention, the reinforced plate  5  formed into a specific shape shown in  FIG. 7  is installed in the direction D 3  in such a manner that the buffer plate  6  is in contact with the display screen  1   a  ( FIG. 2 ) and the top side of the thin display apparatus  50  is inserted between the inner surfaces  5   d  and  5   f.    
     Next, as shown in  FIG. 5 , a cushion  7  (which will be described later in detail) is installed between the corner cushions  4   a  and  4   d  in a direction D 4  from the top side. 
     Then, the thin display apparatus  50  is packed in a package box  8 , with the corner cushions  4   a  to  4   d , the reinforced plate  5  and the cushion  7  attached thereto. The package box  8  is then closed by folding flaps  8   f , thus completing a packing operation. 
     The cushion  7  is described in detail. 
     The cushion  7  is made of a buffer material such as styrene form. The cushion  7  supports the center region of the thin display apparatus  50  at the top side with the reinforced plate  5 , which will be described with reference to  FIGS. 8 to 12 . 
       FIG. 8  is a sectional view taken on line S 2 A-S 2 A of  FIG. 5 .  FIG. 9  is a sectional view taken on line S 2 B-S 2 B of  FIG. 5 .  FIG. 10  is a partially enlarged view of  FIG. 9  at the top side.  FIG. 11  is an enlarged view of an area DT shown in  FIG. 10 .  FIG. 12  is a schematic view illustrating the dimension of the components. 
     As shown in  FIG. 8 , the cushion  7  has a width W 4  in the lateral direction, equal to or little bit smaller than a width W 3  that is a gap between the corner cushions  4   c  and  4   d . The width adjustment allows that the three cushions  4   c ,  7  and  4   d  are tightly aligned in the lateral direction at the top side of the thin display apparatus  50 . 
     The cushion  7  is provided with a slit  7   a  at the center region in cross section, as shown in  FIGS. 9 and 10 . The slit  7   a  is formed by an inner surface  7   a   1  at the front side and an opposing inner surface  7   a   2  at the rear side. The inner surfaces  7   a   1  and  7   a   2  are slopes to shape the slit  7   a  open wide gradually in the bottom direction in  FIG. 9 . The inner surface  7   a   2  at the rear side is provided with several ribs  7   a   3  aligned in the lateral direction, each having an end surface almost orthogonal to the top-to-bottom direction, as shown in  FIG. 8 . 
     The slit  7   a  has a width T 5  at the bottom thereof as shown in  FIG. 10 , which corresponds to the width obtained by adding the width T 1  ( FIG. 2 ) of the thin display apparatus  50  and a width twice that of the reinforced plate  5 . The cushion  7  thus can be attached to the thin display apparatus  50  tightly in a front-to-rear direction of the apparatus  50  in a manner that the top side of the apparatus  50  is inserted into the slit  7   a  with the reinforced plate  5  between the cushion  7  and the apparatus  50 . 
     Moreover, the cushion  7  has a specific outer width in the front-to-rear direction of the thin display apparatus  50 , that is equal to or little bit smaller than an inner width of the package box  8  in the front-to-rear direction. The width adjustment allows that the cushion  7  is tightly installed in the package box  8  in the front-to-rear direction. The same goes for the corner cushions  4   a  to  4   d.    
     Accordingly, the thin display apparatus  50  is packed in the package box  8  tightly in the front-to-rear and lateral directions, with the corner cushions  4   a  to  4   d , the reinforced plate  5  and the cushion  7 . 
     As shown in  FIG. 10 , the slit  7   a  of the cushion  7  is formed with a tilt angle θ 7  of, for example, about 4 degrees for the slope of the inner surface  7   a   1  with respect to the vertical line that goes through the cushion  7  in a direction orthogonal to the front-to-rear direction of the thin display apparatus  50 . 
     The tilt angle θ 7  is decided in accordance with the relationship between a distance Dm 2  in the top-to-bottom direction and a width T 4  of the buffer plate  6  in the front-to-rear direction, in  FIG. 7 . The distance Dm 2  is defined as a distance between the crease lines  5   c  and the inner surface  5   e  between the crease lines  5   a  and  5   b.    
     The tilt angle θ 7  is discussed in detail. In  FIG. 11 , an enlarged view of the area DT in  FIG. 10 , the display screen  1   a  is positioned far back (in the right direction in  FIG. 11 ) by Δd from the front side  2   b  of the cabinet  2 . 
     It is preferable that the buffer member  6  is in almost surface contact with the display screen  1   a  or they face with each other with an extremely small gap when the thin display apparatus  50  is packed in the package box  8 . 
     In order to satisfy the positional relationship between the buffer member  6  and the display screen  1   a , the following expression (1) is given when the buffer member  6  has a thickness T 4 , according to  FIG. 12 : 
       tan θ7=( T 4−Δ d )/ Dm 2  (1)
 
     wherein T 4 =10 mm, Δd=1.5 mm, and Dm 2 =120 mm, in this embodiment. 
     Under the requirements discussed above, an outer surface  5   fr  ( FIG. 7 ), the opposite surface of the inner surface  5   f  of the reinforced plate  5 , is in almost surface contact with the front-side inner surface  7   a   1  ( FIG. 10 ) of the slit  7  of the cushion  7  when the thin display apparatus  50  is packed in the package box  8 . 
     Referring to  FIG. 8  again, the ribs  7   a   3  are provided in order for the inner surface  5   d  ( FIG. 7 ) of the reinforced plate  5  to be in surface contact with the rear surface of the cabinet  2 . The ribs  7   a   3  are aligned at a specific interval in the lateral direction in  FIG. 8 , with a specific width and height. 
     The ribs  7   a   3  provided as described above are deformed when an external force is applied from the front to rear of the thin display apparatus  50  or the package box  8  falls down in the rear direction, in  FIG. 5 , after the thin display apparatus  50  has been packed in the package box  8 . The deformed ribs  7   a   3  effectively absorb the kinetic energy of the thin display apparatus  50  in accordance with the motion of the display apparatus  50  in the rear direction, thus exhibiting preferable buffer effects. 
     According to the packing method and package structure of the embodiment described above, the thin display apparatus  50 , an article to be packed, is tightly supported by the corner cushions  4   a  to  4   d  at the four corners at the top and bottom sides and also the cushion  7  interposed between the corner cushions  4   c  and  4   d  at the top side, in the package box  8 . 
     The thin display apparatus  50 , an article to be packed, is therefore protected from being deformed at the top side even if the display apparatus  50  falls down in the front or rear side because it is supported by the corner cushions  4   c  and  4   d , and also the cushion  7  at the top side. 
     Moreover, when the thin display apparatus  50  is packed in the package box  8 , with the reinforced plate  5 , the corner cushions  4   c  and  4   d , and the cushion  7 , the buffer plate  6  is put in almost surface contact with an specific area of the display screen  1   a  including the center region thereof or put in a position to face the specific area with a very small gap. The reinforced plate  5  having the buffer plate  6  is restricted from being deformed in the front direction by the cushion  7  at the inner surface  7   a   1  thereof at the front side. Therefore, when the cell panel  1   s  ( FIGS. 2 and 11 ) of the thin liquid crystal display panel  1  is vibrated in the front-to-rear direction, the vibration is diminished by the buffer plate  6  installed as described above. 
     Furthermore, the crease lines  5   a ,  5   b  and  5   c  made in the direction orthogonal to the direction of the flute, as shown in  FIG. 6 , give higher stiffness to the reinforced plate  5  having the buffer plate  6  against the deformation in the front-to-rear direction, which further restricts the cell panel is from being vibrated. 
     When the reinforced plate  5  is made of a corrugated cardboard, the type of flute, the material type of corrugated cardboard core, etc., and the direction of flute can be appropriately selected so that the cell panel  1   s  can be effectively restricted from vibration. 
     With the reinforced plate  5  described above, the cell panel  1   s  protected from being damaged, especially, at the back thereof because of no contact (rubbing, hitting, etc.) with an optical panel (not shown) provided just behind the cell panel  1   s.    
     Moreover, the reinforced plate  5  can be attached to an article to be packed, such as the thin display apparatus  50 , after the article is packed in the package box  8 , thus an easier and more efficient packing operation is achieved. 
     Furthermore, even if the reinforced plate  5  has to be replaced with a new one after packed due to defectiveness after packed, it can be replaced with no need to pick up a packed article, such as the thin display apparatus  50  from the package box  8 , thus higher packing operability is achieved. 
     It is further understood by those skilled in the art that the foregoing description is a preferred embodiment of the described structure and method and that various changes and modifications may be made in the invention without departing from the spirit and scope thereof. 
     For example, the reinforced plate  5  may be made of other materials than a corrugated cardboard, such as resin, like polypropylene (PP). 
     An article to be packed may be the thin liquid crystal display panel  1  without being installed in the thin display apparatus  50 , or other thin plate-like materials such as glass and resin. 
     Regarding the buffer plate  6  to be put in contact with the display screen  1   a  on the cell panel is of the display panel  1 , its position of contact, area and shape are not limited to those described above. Nevertheless, it is preferable that the buffer plate  6  covers the center region of the display screen  1   a , the center region being to be vibrated most when the package box  8  falls down. 
     Shown in  FIG. 13  is a modification to the package structure described above, with a cushion  71  having an integral structure of the corner cushions  4   c  and  4   d , and the cushion  7 . 
     Also in this modification, the thin display apparatus  50  (an article to be packed) is tightly supported by the cushion  71  at the top side from left to right corners. 
     The cushion  71  has a larger exterior dimension than each of the separate corner cushions  4   c  and  4   d , and cushion  7 . However, the use of the cushion  71  reduces the cushion installation steps of ⅓ fewer than those separated cushions. 
     Also in this modification, a packed article is protected from being damaged at the top side when a package box falls down in front or rear because it is supported or protected at the top side. 
     As described in detail, the present invention achieves that a packed article, such as a thin liquid crystal display panel and a thin display apparatus and so on, is packed in a package box by an easier operation and is protected from being deformed even if a package box falls down.