Patent Abstract:
The present invention relates to a flat panel display having integral fastening structures for holding the top and bottom chassis. The flat panel display comprises a mold frame enclosing an internal storage space and having a plurality of fastening hooks protruding outward from a side surface thereof; a bottom chassis having a plurality of first coupling openings fastened to the plurality of fastening hooks of the mold frame; and a top chassis having a fastening structure fastened to the bottom chassis, wherein the fastening structure is formed on the area where the mold frame is fastened to the bottom chassis.

Full Description:
RELATED APPLICATIONS  
       [0001]     This application claims priority under 35 U.S.C. §119 of Korean Patent Application No. 10-2005-0121734, filed Dec. 12, 2005, the disclosure of which is incorporated herein by reference in its entirety.  
       BACKGROUND  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to integral fastening structures for holding together the top and bottom chassis of flat panel displays, and flat panel displays incorporating the same.  
         [0004]     2. Related Art  
         [0005]     Among flat panel displays, the application range of liquid crystal displays (LCDs) has been extended because of its light weight, thinness, low drive power requirements, full color capabilities and high resolution characteristics. LCDs are currently used in computers, notebook computers, PDAs, telephones, TVs, audio/video devices and the like. Such LCD panels are used to modulate light transmitted by the panels in accordance with image signals applied to control switches arrayed in a matrix therein and then display a desired image on a surface of the display. The LCD device comprises an LCD panel having a surface on which images are displayed directly, an LCD drive IC for operating the LCD panel, a backlight unit used as a light source of the LCD, and a chassis used to fasten respective components of the LCD into a single, integrated panel unit.  
         [0006]     Recently, two features have emerged as being of major interest to users of medium- or small-sized LCDs, viz., a high luminance and a reduced thickness. The latter feature is one of particular importance to manufacturers of host devices that incorporate LCD panels, and accordingly, a variety of fastening structures have been developed with a view towards reducing panel thickness. Among the various prior art fastening structures that have been developed, the most commonly employed structure is one in which a flange-shaped fastening portion is formed on a module of an LCD that is to be incorporated in the host device, as illustrated in  FIG. 1 .  
         [0007]      FIG. 1  is a perspective view of a generic LCD. With referring to  FIG. 1 , the LCD comprises an LCD panel  10 , a mold frame  20  in which the LCD panel  10  is received, and a bottom chassis  30  that is fastened to the mold frame  20 . A flange-shaped fastening portion  25  is formed on a side surface of the mold frame  20  and is used to fasten the LCD to a host device.  
         [0008]      FIGS. 2A and 2B  are upper front perspective and side elevation views, respectively, of an LCD incorporating dual liquid crystal panels in accordance with the prior art. Referring to  FIGS. 2A and 2B , the LCD comprises a sub-side LCD panel  10 , a mold frame  20  for accommodating a backlight unit therein, and a bottom chassis  30  fastened to the mold frame  20 . Additionally, a flange-shaped fastening portion  25  is formed on a side surface of the mold frame  20  for fastening the LCD to a host device. The sub-side LCD panel  10  is disposed on an outer side of the bottom chassis  30 , and a main-side LCD panel (not illustrated) is disposed on an opposite side of the mold frame  20 .  
         [0009]      FIGS. 3A and 3B  are enlarged plan and cross-sectional views, respectively, of the regions encircled by phantom lines in  FIGS. 1 and 2 B, showing corresponding portions of the LCD mold frame  20  and bottom chassis  30  at which the chassis portions are fastened together in accordance with the prior art fastening structure. Referring to these figures, a hook  23 , which protrudes a selected distance outward, is formed on a side surface of the mold frame  20 . A coupling opening  35  corresponding to the shape and location of the hook  23  is formed in a sidewall of the bottom chassis  30 , together with a rectangular hook fixing portion  33 , which tapers inwardly from the sidewall of the bottom chassis. The resilient material of the mold frame and chassis enable the two fastening portions to be pressed together in an over-center, snap-in locking engagement with each other to fasten the two parts together.  
         [0010]     In the prior art fastening structure described above, flange-shaped fastening portions are formed on a side surface of the mold frame for fastening the panel to the host device. However, as will be appreciated, there are many constraints on the design of the side surfaces of an LCD. In particular, the space needed for the hooks used to fasten the bottom chassis to the top chassis is insufficient due to the presence of the flange-shaped fastening portions. As a result, the size and/or number of the hooks must be decreased, and hence, the strength of the joints that fasten the top and bottom chassis together is correspondingly reduced. This, in turn, substantially reduces the ability of the LCD panel to withstand external shocks and impacts acting on the panel.  
       BRIEF SUMMARY  
       [0011]     The present invention has been conceived to overcome the aforementioned problems of the prior art fastening structures. In accordance with the exemplary embodiments thereof described herein, the present invention provides a flat panel display having top and bottom chassis which incorporate an integrated fastening structure that not only optimally utilizes the limited space available on a side surface of a flat panel display after the provision thereon of panel-to-host fastening features, but also substantially increases the strength of the joints used to fasten the top and bottom chassis together.  
         [0012]     According to an exemplary embodiment, a flat panel display comprises a mold frame enclosing an internal storage space and having a plurality of fastening hooks protruding outward from a side surface thereof, a bottom chassis having a plurality of first coupling openings fastened to the plurality of fastening hooks of the mold frame; and a top chassis having a fastening structure fastened to the bottom chassis, wherein the fastening structure is formed on the area where the mold frame is fastened to the bottom chassis.  
         [0013]     A better understanding of the above and many other features and advantages of the display fastening structures of the present invention and the displays incorporating them may be obtained from the detailed description of the exemplary embodiments thereof below, particularly if such consideration is made in conjunction with the several views of the appended drawings, wherein like reference numerals are used to identify like elements illustrated in one or more of the figures thereof. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is an upper front perspective view of an exemplary embodiment of a generic liquid crystal display (LCD) in accordance with the prior art;  
         [0015]      FIGS. 2A and 2B  are upper front side perspective and side elevation views, respectively, of an exemplary LCD incorporating a dual liquid crystal panel in accordance with the prior art;  
         [0016]      FIGS. 3A and 3B  are enlarged partial side elevation and cross-sectional views, respectively, of adjacent portions of a mold frame and a bottom chassis of an LCD incorporating a fastening structure of the prior art for fastening the two chassis components together;  
         [0017]      FIGS. 4A and 4B  are partial side elevation and upper side perspective views, respectively, of an exemplary first embodiment of a fastening structure for fastening a top and bottom chassis of an LCD together in accordance with the present invention, showing the chassis components prior to being fastened together;  
         [0018]      FIGS. 4C and 4D  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis of  FIGS. 4A and 4B  after being fastened together;  
         [0019]      FIGS. 5A and 5B  are partial side elevation and an upper side perspective views, respectively, of an exemplary second embodiment of a fastening structure for fastening a top and bottom chassis of an LCD together in accordance with the present invention, showing the chassis components prior to being fastened together;  
         [0020]      FIGS. 5C and 5D  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis of  FIGS. 5A and 5B  after being fastened together;  
         [0021]      FIGS. 6A and 6B  are partial side elevation and upper side perspective views, respectively, of an exemplary third embodiment of a fastening structure for fastening a top and bottom chassis of an LCD together in accordance with the present invention, showing the chassis components prior to being fastened together;  
         [0022]      FIGS. 6C and 6D  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis of  FIGS. 6A and 6B  after being fastened together;  
         [0023]      FIGS. 7A and 7B  are partial side elevation and upper side perspective views, respectively, of an exemplary fourth embodiment of a fastening structure for fastening a top and bottom chassis of an LCD together in accordance with the present invention, showing the chassis components prior to being fastened together; and,  
         [0024]      FIGS. 7C and 7D  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis of  FIGS. 7A and 7B  after being fastened together. 
     
    
     DETAILED DESCRIPTION  
       [0025]      FIGS. 4A and 4B  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis  100  and  200  of an LCD prior to being fastened together with an exemplary first embodiment of a fastening structure in accordance with the present invention. As illustrated in  FIGS. 4A and 4B , the LCD of the first embodiment comprises a top chassis  100 , a bottom chassis  200  and a mold frame  300 . The mold frame  300  defines an internal storage space for accommodating a backlight unit and an LCD panel (not illustrated). The bottom chassis  200  is fastened together with the mold frame  300  to surround the bottom and side surfaces of the mold frame  300 , and the top chassis  100  is fastened together with the bottom chassis  200  to surround a portion of the top surface of the LCD panel and the side surfaces of the mold frame  300 .  
         [0026]     As may be seen by reference to the figures, the top chassis  100  comprises a base plate  110  that includes an opening (not illustrated) through which a display surface of the LCD panel is exposed to the outside, a generally vertical sidewall  120 , and a fastening portion  130  that is formed on the sidewall  120  to extend perpendicularly downward from the base plate and be fastened together with the bottom chassis  200  in the manner described below. In the first exemplary embodiment illustrated, only a portion of the sidewall  120  of the top chassis  100  containing a single fastening portion  130  is shown for convenience of illustration. However, it should be understood that a plurality of the fastening portions  130  can be formed on the sidewall  120  of the base plate of the top chassis.  
         [0027]     As illustrated in  FIGS. 4A and 4B , a rectangular coupling opening  133  is formed near the center of the fastening portion  130 , and a semi-hemispherical protrusion  135   a  is formed immediately below the coupling groove  133  to protrude inward from the fastening portion  130 . The inward protrusion  135   a  may be formed integrally with, e.g., molded in, the fastening portion  130  during manufacture. Additionally, although the protrusion  135   a  of the exemplary embodiment is illustrated as being semi-hemispherical in shape, the present invention is not limited thereto. That is, the protrusion  135   a  may be formed with various other shapes.  
         [0028]     The bottom chassis  200  of the first embodiment comprises a base plate  210  that extends around a bottom surface of the mold frame  300 , a generally vertical sidewall  220  that extends perpendicularly upward from an edge of the base plate  210 , a rectangular coupling opening  230  formed in the sidewall  220  for coupling with a hook  310  of the mold frame  300  described below, and a semi-hemispherical protrusion  240   a  formed immediately above the coupling groove  230  to protrude outward from the sidewall  220  for fastening with the top chassis  100 . Like the inward protrusion  135   a  above, the outward protrusion  240   a  may be integrally formed with, e.g., molded in, the sidewall  220  during manufacture, and likewise, may be formed in a variety of shapes. Further, it should be understood that, although only a portion of the sidewall  220  of the bottom chassis  200  containing a single coupling opening  230  and outward protrusion  240   a  is shown in the first embodiment for convenience of illustration, a plurality of the coupling openings  230  and associated protrusions  240   a  can be provided, and in general, the fastening structures of the top chassis  100  and bottom chassis  200  of the present invention are provided in corresponding pairs.  
         [0029]     As described above, the mold frame  300  defines an internal space for accommodating a backlight unit, an LCD panel and the like, and a fastening hook  310  of a selected length is formed on a side surface of the mold frame  300  to protrude outward therefrom such that it can be fastened together with the top and bottom chassis  100  and  200 . As illustrated in the figures, the fastening hook  310  is arranged to extend through the rectangular coupling opening  230  of the bottom chassis  200 .  
         [0030]      FIGS. 4C and 4D  are partial side elevation and upper side perspective views, respectively, showing the top and bottom chassis of the LCD after they have been fastened together with the exemplary first embodiment of the fastening structure of the present invention. As may be seen in the figures, when the top chassis  100  is fastened to the bottom chassis  200 , the coupling opening  133  of the fastening portion  130  of the top chassis  100  is coupled to and fixed with the outward protrusion  240   a  formed on the sidewall  220  of the bottom chassis  200 , and the inward protrusion  135   a  on the coupling portion  130  of the top chassis  100  is correspondingly coupled to and fixed with the bottom chassis  200  while pushing against the fastening hook  310  of the mold frame  300 . Thus, the force holding the top and bottom chassis  100  and  200  to each other is substantially increased, and further, since the top and bottom chassis  100  and  200  are fastened to each other within the same, relatively small regions, the space on the side surface of an LCD necessary to effect the improved fastening is substantially decreased.  
         [0031]      FIGS. 5A and 5B  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis  100  and  200  of an LCD prior to being fastened together with an exemplary second embodiment of a fastening structure in accordance with the present invention. In  FIGS. 5A and 5B , the LCD of the second embodiment, like the first, comprises a top chassis  100 , a bottom chassis  200  and a mold frame  300 .  
         [0032]     The top chassis  100  comprises a base plate  110  that includes an opening (not illustrated) through which a display surface of the LCD panel (not illustrated) is exposed to the outside, a generally vertical sidewall  120 , and a fastening portion  130  that is formed on the sidewall  120  to extend perpendicularly downward from the base plate and be fastened with the bottom chassis  200 , as described below. As above, it should be understood that, although only a portion of the sidewall  120  of the top chassis  100  is shown for convenience of illustration, a plurality of the fastening portions  130  can be formed on the sidewall  120 .  
         [0033]     A cylindrical protrusion  135   b  is formed in a specific region of the fastening portion  130  to protrude inward from the fastening portion. The inward protrusion  135   b  can be integrally formed with, e.g., molded into, the fastening portion  130  during manufacture, and further, although shown as cylindrical in shape, may incorporate a shape other than cylindrical.  
         [0034]     The bottom chassis  200  comprises a base plate  210  that surrounds a bottom surface of the mold frame  300 , a generally vertical sidewall  220 , and a rectangular coupling opening  230  formed in the sidewall  220  for coupling with a fastening hook  310  of the mold frame  300 , as described below. And as above, although only a single coupling opening  230  is shown in the figure, a plurality of the coupling openings  230  corresponding to the number of the top panel fastening structures are generally provided in the sidewall  220 .  
         [0035]     A fastening hook  310  having a selected length is formed on a side surface of the mold frame  300  to protrude outwardly such that it can be fastened together with the top chassis  100  and the bottom chassis  200 . The mold frame  300  is positioned on the bottom chassis such that the fastening hook  310  extends through the coupling opening  230  of the bottom chassis  200 . Further, the hook  310  has a width selected such that, when the hook is disposed at one side of the rectangular opening  230  of the sidewall, a second coupling opening  315  with a specific shape, size and location is defined adjacent to the hook  310 . In particular, the size and location of the opening  315  correspond to those of the inwardly extending protrusion  135   b  of the fastening portion  130  of the top chassis  100 .  
         [0036]      FIGS. 5C and 5D  are partial side elevation and upper side perspective views, respectively, showing the top and bottom chassis of the LCD after they have been fastened together with the exemplary second embodiment of the fastening structure of the present invention. As shown in the figures, when the top chassis  100  is fastened to the bottom chassis  200 , the protrusion  135   b  on the fastening portion  130  of the top chassis  100  extends into and interlocks with the opening  315  formed adjacent to the fastening hook  310  of the mold frame  300 .  
         [0037]      FIGS. 6A and 6B  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis  100  and  200  of an LCD prior to being fastened together with a fastening structure in accordance with an exemplary third embodiment of the present invention. The third embodiment differs from the second embodiment primarily in the location of the opening used to couple with protrusions of the top chassis and mold frame, but in other respects, the two embodiments are otherwise very similar to each other. Thus, the following description focuses on the differences between the two embodiments.  
         [0038]     As illustrated in  FIGS. 6A and 6B , the LCD of the third embodiment comprises a top chassis  100 , a bottom chassis  200  and a mold frame  300 . The top chassis  100  comprises a base plate  110  that includes an opening (not illustrated) through which a display surface of the LCD panel (not illustrated) is exposed to the outside, a generally vertical sidewall  120 , and a fastening portion  130  that is formed on the sidewall  120  to extend perpendicularly downward from the base plate and be fastened together with the bottom chassis  200 . A cylindrical protrusion  135   b  is formed on a predetermined region of the fastening portion  130  to protrude inward from the fastening portion, and as above, the protrusion  135   b  may be integrally formed with the fastening portion  130 , and include a shape other than cylindrical.  
         [0039]     The exemplary third embodiment includes a fastening hook  310  having a selected length formed on a side surface of the mold frame  300  such that it can be fastened together with the top and bottom chassis  100  and  200 , as described below. As illustrated in the figures, the hook  310  is bifurcated to define a recess  315  of a selected size in the center of the hook  310 . In particular, the recess  315  is sized and located to correspond to the size and location of the inward protrusion  135   b  of the top chassis  100 .  
         [0040]      FIGS. 6C and 6D  are partial side elevation and upper side perspective views, respectively, showing the top and bottom chassis of the LCD after they have been fastened together with the exemplary third embodiment of the fastening structure of the present invention. As illustrated in the figures, when the top chassis  100  is fastened onto the bottom chassis  200 , the inward protrusion  135   b  on the fastening portion  130  of the top chassis  100  extends into and interlocks with the recess  315  formed at the center of the fastening hook  310 .  
         [0041]      FIGS. 7A and 7B  are partial side elevation and upper side perspective views, respectively, of the top and bottom chassis  100  and  200  of an LCD prior to being fastened together with an exemplary fourth embodiment of a fastening structure in accordance with the present invention. As in the other exemplary embodiments above, the top chassis  100  comprises a base plate  110  that includes an opening (not illustrated) through which a display surface of the LCD panel is exposed to the outside, a generally vertical sidewall  120 , and a fastening portion  130  that is formed on the sidewall  120  to extend perpendicularly downward from the base plate and be fastened together with the bottom chassis  200 . And as in the above exemplary embodiments, although only a single fastening structure is shown, it should be understood that a plurality of corresponding pairs of the structures can be provided.  
         [0042]     A cylindrical protrusion  135   c  is formed in a predetermined region of the fastening portion  130  to protrude inwardly from the fastening portion  130 . As above, the protrusion  135   c  may be integrally formed with the fastening portion  130 , and may incorporate a shape other than cylindrical, e.g., hemispherical.  
         [0043]     The bottom chassis  200  comprises a base plate  210  which surrounds a bottom surface of the mold frame  300 , a vertical sidewall  220  that extends upward from an edge of the base plate  210 , a coupling opening  230  formed on the sidewall  220  for coupling with a fastening hook  310  of the mold frame  300  described below, and a cylindrical protrusion  240   c , which may be integrally formed with the sidewall  220 , disposed immediately above the coupling groove  230  to protrude inwardly from the sidewall  220  and be fastened with the top chassis  100 . Like the inward protrusion  135   a  of the fastening portion  130 , the inward protrusion  240   c  may various shapes other than cylindrical, e.g., hemispherical. However, the protrusion  240   c  of the bottom chassis  200  and the protrusion  135   c  of the top chassis  100  are preferably formed at positions and incorporate shapes that correspond to each other. Additionally, it is preferred that the protrusion  240   c  of the bottom chassis  200  be formed slightly larger than the protrusion  135   c  of the top chassis  100 .  
         [0044]     As described above, a fastening hook  310  having a selected length is formed on a side surface of the mold frame  300  for fastening of the latter with the top and bottom chassis  100  and  200 , with the hook  310  arranged to extend outwardly into the coupling opening  230  of the bottom chassis  200 .  
         [0045]      FIGS. 7C and 7D  are partial side elevation and upper side perspective views, respectively, showing the top and bottom chassis of the LCD after they have been fastened together with the exemplary fourth embodiment of the fastening structure of the present invention. As illustrated in the figures, when the top chassis  100  is fastened onto the bottom chassis  200 , the fastening hook  310  of the mold frame  300  extends into the coupling opening of  230  of the bottom chassis  200 , and the inward protrusion  240   c  on the sidewall  220  of the bottom chassis  200  pushes against the side of the mold frame  300 , and since it is arranged above the hook  310  of the mold frame  300 , simultaneously locks the hook  310  in position. Further, the inward protrusion  135   c  of the top chassis  100  engages and locks into the inward protrusion  240   c  formed on the sidewall  220  of the bottom chassis  200 .  
         [0046]     According to the exemplary embodiments of the present invention described above, top and bottom LCD panel chassis are formed with integrated fastening structures that advantageously increase the available useable space on the side surfaces the display while enhancing the fastening forces holding the chassis components together. Additionally, the novel chassis fastening structures enable a desirable reduction in design constraints to be achieved in the design of the panel-to-host fastening devices.  
         [0047]     Although the exemplary embodiments have been described and illustrated herein in conjunction with LCD panels, it should be understood that the present invention is not limited such display types. For example, the present invention can also be applied to a variety of other types of displays, such as an organic light emitting diode display (“OLED”), which uses the electroluminescence principle for generating light, or a plasma display panel (“PDP”) display in which a plurality of small cells are arranged between two substrates and a gas (neon or argon) discharge is generated between electrodes (positive and negative) above and below the substrates such that the cells cause self luminescence by means of ultraviolet rays generated due to the gas discharge, thereby reproducing color images, or like displays. Accordingly, the scope of the present invention should not be limited to that of the particular embodiments illustrated and described herein, as they are only exemplary in nature, but instead, should be fully commensurate with that of the claims appended hereafter and their functional equivalents.

Technology Classification (CPC): 6