Abstract:
A liquid crystal display includes a cover bottom and a cover shield. The liquid crystal display includes a nut coupled to a bracket through a fastening bolt. An upper portion and a lower portion of the nut have different diameters.

Description:
[0001]    This application claims the benefit of Korean Patent Application No. 2007-016119 filed on Feb. 15, 2007, which is hereby incorporated by reference as if fully set forth herein. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a liquid crystal display, and more particularly to a liquid crystal display with a modified nut structure to be fastened to a main body of a system. 
         [0004]    2. Discussion of the Related Art 
         [0005]    A liquid crystal display is configured by coupling a liquid crystal panel and a back light unit. Since the liquid crystal display is not a self-emission display device, the liquid crystal display requires a back light unit including a light source. 
         [0006]    The back light unit including a light source may be classified into a direct-type back light unit and an edge-type back light unit according to the position of the light source. 
         [0007]    In the direct-type back light unit, a number of light sources are disposed directly below a liquid crystal panel to irradiate light projected from the light sources onto the liquid crystal panel through a diffusion plate and a number of optical sheets. A general liquid crystal display including the direct-type back light unit is configured such that the liquid crystal panel and the back light unit are fastened to each other by a support main, a top case, a bottom cover and the like. 
         [0008]    In the edge-type back light unit, a light source is installed at one side edge of a liquid crystal panel to irradiate light projected from the light source onto the liquid crystal panel through a light guiding plate and a number of optical sheets. 
         [0009]      FIG. 1  illustrates an exemplary diagram showing a rear surface of a general liquid crystal display, which shows a connection state of the rear surface of the general liquid crystal display and a bracket. 
         [0010]    The liquid crystal display is used as a component of a relatively large-scale system such as a monitor, a laptop computer or a TV, and also used as a component of a small-scale application (system) such as a navigation system, a PDP or a PMP. Generally, the liquid crystal display is manufactured through a separate process and is coupled to a main body of the system to be mounted in one case for sale. 
         [0011]    As described above, generally, a bracket  20  shown in  FIG. 1  is used to couple a liquid crystal display  10  to a main body of a system. 
         [0012]    Three holes  21 ,  22 ,  23  are formed at each of an upper portion and a lower portion of the bracket  20 . A guide pin  11  formed on a lower surface of the liquid crystal display  10  is inserted into the first hole  21  among the three holes  21 ,  22 ,  23 . A first fastening bolt  30  is inserted into the second hole  22  to be fastened to a nut  14  formed on the lower surface of the liquid crystal display  10 . A second fastening bolt (not shown) is inserted into the third hole  23  to be fastened to the main body. 
         [0013]      FIG. 2  illustrates a cross-sectional view showing a state where the liquid crystal display and the bracket shown in  FIG. 1  are fastened to each other by the fastening bolt. 
         [0014]    In general, as shown in  FIGS. 1 and 2 , the nut  14  is formed on a cover bottom  13  which supports a lower surface of the liquid crystal display  10 . The first fastening bolt  30  inserted into the second hole  22  of the bracket  20  is fastened to the nut  14  through a cover shield hole  16  formed on a cover shield  15  surrounding the cover bottom  13 . Further, the second fastening bolt  40  inserted into the third hole  23  of the bracket  20  is fastened to a nut formed on the main body (not shown) of the system. 
         [0015]    Before the first fastening bolt  30  is coupled to the nut  14  as described above, the second hole  22  of the bracket  20  should correspond to a position of the nut  14  (the cover shield hole  16  and the nut  14  have been already aligned). In the related art, the guide pin  11  which is formed on the cover bottom  13  or the cover shield  15  is used to align the second hole  22  corresponding to the nut  14 . 
         [0016]    That is, the guide pins  11  are formed on an upper portion and a lower portion of the rear surface of the related art liquid crystal display, respectively. The guide pins  11  are inserted into the first holes  21  respectively formed on the upper portion and the lower portion of the bracket, thereby arranging the second holes  22  of the bracket and the nut  14 . 
         [0017]    However, in order to couple the bracket  20  to the related art liquid crystal display  10  as described above, first, a process for inserting the guide pin  11  formed on the rear surface of the liquid crystal display into the first hole  21  of the bracket  20  to align positions of the second hole  22  of the bracket and the nut  14  should be performed. Then, a process for coupling and fastening the first fastening bolt  30  inserted into the second hole  22  to the nut  14  should be performed. 
         [0018]    Accordingly, a pair of the guide pin  11  and the cover shield hole  16  having a specified interval should be formed at each of an upper portion and a lower portion of the rear surface of the related art liquid crystal display. Thus, for formation of the guide pin  11  and the cover shield hole  16 , an elaborate process is required. Also, there is a problem of increasing the manufacturing cost and the cost of parts due to a complicated structure. 
         [0019]    Further, since the related art liquid crystal display requires a process for forming fine holes, although an alignment process using the guide pins  11  is performed, the first fastening bolt  30  may be inaccurately inserted into the second hole  22  and the nut  14  due to an error generated in the alignment of the second hole  22  of the bracket  20  and the nut  14 . 
       SUMMARY OF THE INVENTION 
       [0020]    Accordingly, the present invention is directed to a liquid crystal display that substantially obviates one or more problems due to limitations and disadvantages of the related art. 
         [0021]    An advantage of the present invention is to provide a liquid crystal display which performs an alignment function with a bracket and has a nut coupled to the bracket through a fastening bolt. 
         [0022]    Additional features and advantages of the invention will be set forth in the description which follows and in part will become apparent from the description, or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
         [0023]    To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described, a liquid crystal display having a cover bottom and a cover shield, includes a nut coupled to a bracket through a fastening bolt, wherein an upper portion and a lower portion of the nut have different diameters. 
         [0024]    It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principle of the invention. 
           [0026]    In the drawings: 
           [0027]      FIG. 1  is an exemplary diagram showing a rear surface of a related art liquid crystal display; 
           [0028]      FIG. 2  is a cross-sectional view showing a state where the liquid crystal display and a bracket shown in  FIG. 1  are fastened to each other by a fastening bolt; 
           [0029]      FIG. 3  is a configuration of a liquid crystal display using an edge-type back light unit according to one embodiment of the present invention; 
           [0030]      FIG. 4  is a configuration of a liquid crystal display using a direct-type back light unit according to another embodiment of the present invention; 
           [0031]      FIG. 5  is an exemplary diagram showing a rear surface of the liquid crystal display according to embodiments of the present invention; and 
           [0032]      FIG. 6  is a cross-sectional view showing a state where the liquid crystal display and a bracket shown in  FIG. 5  are fastened to each other by a fastening bolt. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0033]    Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
         [0034]      FIG. 3  illustrates a configuration of a liquid crystal display using an edge-type back light unit according to one embodiment of the present invention, particularly, a configuration of a liquid crystal display which may be applied to a small-scale application (system) such as a navigation system mounted and used in a vehicle. 
         [0035]    As shown in  FIG. 3 , the liquid crystal display using an edge-type back light unit according to the embodiment of the present invention includes a liquid crystal display panel  120 ; a back light unit  140  which irradiates light onto the liquid crystal display panel  120 ; a cover bottom  150  which receives the liquid crystal display panel  120  and the back light unit  140 ; a guide panel  130  which is disposed between the back light unit  140  and the liquid crystal display panel  120  to support the liquid crystal display panel  120  and also to be fastened to a side surface of the cover bottom  150 ; a top case  110  which covers a periphery of the liquid crystal display panel  120  and a sidewall of the guide panel  130 ; and a cover shield  160  which entirely protects the components on a rear surface of the liquid crystal display. 
         [0036]    In a liquid crystal panel  127  of the liquid crystal display panel  120 , liquid crystal cells are arranged in an active matrix form between an upper substrate  121  and a lower substrate  122 . Further, thin film transistors are formed at the liquid crystal cells, respectively, to switch video signals. The respective refractive indexes of the liquid crystal cells are changed according to the video signals, thereby displaying an image corresponding to the video signals. A tape carrier package  124  with a driver integrated circuit  123  for applying driving signals to the thin film transistors is attached onto the lower substrate  122  of the liquid crystal display panel  120 . Further, a polarizing film  126  is disposed on a front and rear surface of the liquid crystal display panel  120  (front polarizing film is not shown). The polarizing film  126  serves to improve a viewing angle of the image displayed by the liquid crystal cells. 
         [0037]    The back light unit  140  includes a lamp  147  which is supplied with power from an external power source to irradiate light onto the liquid crystal panel  127 ; a light guiding plate  142  which guides light incident through a light incident portion formed on a side surface opposite to the lamp  147  to the liquid crystal panel  127 ; a lamp housing  148  which covers the lamp  147  and the light incident portion of the light guiding plate  142 ; a reflective sheet  143  which is disposed on a rear surface of the light guiding plate  142 ; and a number of optical sheets  141  which improve efficiency of light emitted from the light guiding plate  142  to irradiate the light onto the liquid crystal panel  127 . 
         [0038]    The guide panel  130  bent in an “L” shape is mounted on an upper peripheral surface of the cover bottom  150  and also covers the side surface of the cover bottom  150 . The guide panel  130  includes a mounting portion for mounting a rear surface of the liquid crystal panel  127  and a sidewall for guiding a side surface of the liquid crystal panel  127  to support the liquid crystal panel  127 . 
         [0039]    The top case  110  is manufactured in a rectangular stripe shape having a plane portion and a side portion bent at a right angle. The top case  110  covers the periphery of the liquid crystal panel  127  and the side surface of the cover bottom  150 . 
         [0040]    The cover bottom  150  is a molded structure of a plastic material, wherein an inner sidewall surface thereof is formed as a stepped projection surface. The back light unit  140 , the guide panel  130  and the liquid crystal display panel  120  are stacked on the stepped projection surface of the cover bottom  150 . 
         [0041]    The cover shield  160  functions to entirely protect the above-mentioned components on the rear surface of the liquid crystal display including the above-mentioned components. 
         [0042]    Meanwhile, nuts  170  are formed on one side surface of the cover bottom  150  or the cover shield  160  among the above-mentioned components. The nuts  170  are coupled to a bracket through fastening bolts while performing an alignment of the bracket. The bracket is coupled to a main body of the application (system) through the fastening bolts. 
         [0043]    Also in the following description, the nuts  170  are formed on the cover bottom  150  as shown in  FIG. 3 , but the embodiment of the present invention is not limited thereto. That is, the nuts  170  may be formed on the cover shield  160 . 
         [0044]    The structure and function of the nuts  170  will be described in detail later with reference to  FIGS. 5 and 6 . 
         [0045]      FIG. 4  illustrates a configuration of a liquid crystal display using a direct-type back light unit according to another embodiment of the present invention, particularly, a configuration of a liquid crystal display which may be applied to a small-scale application (system) such as a navigation system mounted and used in a vehicle. In the following description related to  FIG. 4 , the repeated description of the components explained in  FIG. 3  will be given in brief. 
         [0046]    As shown in  FIG. 4 , the liquid crystal display using an direct-type back light unit according to the embodiment of the present invention includes a liquid crystal panel  210 , a back light unit  220 , a support main  240 , a top case  230 , a cover bottom  250  and a cover shield  260 . 
         [0047]    The liquid crystal panel  210  includes two substrates  210   a  and  210   b  facing each other and a liquid crystal layer (not shown) disposed between the two substrates  210   a  and  210   b.    
         [0048]    The back light unit  220  serves to supply light at a lower portion of the liquid crystal panel  210 . A number of lamps  221  of the back light unit  220  serving as a light source are arranged in parallel. A reflective sheet  222  is disposed below the lamps  221  and a number of optical sheets  223  are stacked above the lamps  221 . 
         [0049]    The liquid crystal panel  210  and the back light unit  220  are mounted on the support main  240 . The support main  240  supports the liquid crystal panel  210  and the back light unit  220  while preventing the movement of the liquid crystal panel  210  and the back light unit  220 . 
         [0050]    The top case  230  covers an upper peripheral portion of the liquid crystal panel  210  and a side surface of the support main  240  to support and protect the periphery of the liquid crystal panel  210  and the side surface of the support main  240 . 
         [0051]    The cover bottom  250  covers a lower portion of the support main  240  to protect a lower portion of the liquid crystal display. The cover bottom  250  is fastened to the top case  230  and the support main  240  through a fastening means (not shown) to be modularized. 
         [0052]    The cover shield  260  functions to entirely protect the above-mentioned components on the rear surface of the liquid crystal display including the above-mentioned components. 
         [0053]    Meanwhile, nuts  270  are formed on one side surface of the cover bottom  250  or the cover shield  260  among the above-mentioned components. The nuts  270  are coupled to a bracket through fastening bolts while performing an alignment of the bracket. The bracket is coupled to a main body of the application (system) through the fastening bolts. 
         [0054]    Also in the following description, the nuts  270  are formed on the cover bottom  250  as shown in  FIG. 4 , but the embodiment of the present invention is not limited thereto. That is, the nuts  270  may be formed on the cover shield  260 . 
         [0055]    The structure and function of the nuts  170  and  270  will be described below in detail with reference to  FIGS. 5 and 6 . 
         [0056]      FIG. 5  illustrates an exemplary diagram showing the rear surface of the liquid crystal display according to the embodiments of the present invention, which shows a connection state of the rear surface of the liquid crystal display shown in  FIG. 3  or  4  and the bracket. Further,  FIG. 6  illustrates a cross-sectional view showing a state where the liquid crystal display and the bracket shown in  FIG. 5  are fastened to each other by fastening bolts. 
         [0057]    The embodiments of the present invention relate to a liquid crystal display which is applicable to a small-scale application (system) such as a navigation system mounted and used in a vehicle, a PMP, or a PDA. A liquid crystal display  310  shown in  FIG. 5  may be formed by the components shown in  FIG. 3  or  4 . 
         [0058]    A bracket  320  is used to couple the liquid crystal display  310  to a main body (not shown) of the system. The bracket  320  is fastened to the liquid crystal display  310  through first fastening bolts  330  and is fastened to the main body of the system through second fastening bolts  340 . 
         [0059]    As shown in  FIG. 5 , first fastening holes  321  are respectively formed at an upper end portion and a lower end portion of the bracket  320  for the above-mentioned coupling. 
         [0060]    Meanwhile, as in the above description related to  FIGS. 3 and 4 , nuts (for example, Pem nuts)  370  which are fastened to the first fastening bolts  330  are formed on a cover bottom  313  of the liquid crystal display according to the embodiment of the present invention. As shown in  FIGS. 5 and 6 , guide portions  371  forming upper ends of the nuts  370  are protruded through cover shield holes  316  formed on a cover shield  315  to be inserted into the first fastening holes  321  of the bracket  320 . 
         [0061]    A coupling state of the nuts  370  having the above configuration and the bracket  320  is explained below with reference to  FIG. 6 . 
         [0062]    As described above, the nuts  370  are formed on the cover bottom  313  of the liquid crystal display according to the embodiments of the present invention and the nuts  370  have a two-step configuration. That is, the nuts  370  include support portions  372  coupled to the cover bottom  313  and the guide portions  371  having a diameter smaller than that of the support portions  372 . Thus, the support portions  372  and the guide portions  371  are configured in a stepped projection shape. 
         [0063]    The cover shield  315  is placed on portions which are formed in a stepped projection shape (hereinafter, simply referred to as “stepped projection portions”)  373  of the support portions  372  and the guide portions  371 . Accordingly, the cover shield holes  316  formed on the cover shield  315  may be formed to have a diameter greater than that of the guide portions  371  and smaller than that of the support portions  372 . 
         [0064]    Further, the guide portions  371  may have a length smaller than or equal to the sum of the thickness of the cover shield  315  and the thickness of the bracket  320 . Accordingly, as shown in  FIG. 6 , the guide portions  371  may pass through the cover shield holes  316  formed on the cover shield  315  and the first fastening holes  321  formed on the bracket  320 . 
         [0065]    In order to couple the liquid crystal display  310  having the above configuration and the bracket  320 , first, the guide portions  371  should be inserted into the first fastening holes  321  formed on the bracket  320 . For this, the guide portions  371  are formed to be protruded from the cover shield holes  316  of the cover shield  315  in an assembly step of the liquid crystal display  310 . 
         [0066]    When the guide portions  371  are inserted into the first fastening holes  321 , the first fastening bolts  330  are inserted along screw lines formed on inner surfaces of the guide portions  371 . Since the screw lines are formed from the inner surfaces of the guide portions  371  to the inner surfaces of the support portions  372 , the first fastening bolts  330  may be inserted to the inner surfaces of the support portions  372 . Further, since the diameter of heads  331  of the first fastening bolts  330  is greater than the diameter of the first fastening holes  321  formed on the bracket  320 , the bracket  320  may be fixed between the heads  331  of the first fastening bolts  330  and the stepped projection portions  373  of the nuts  370 . 
         [0067]    Meanwhile, the nuts  370  are respectively formed at an upper portion and a lower portion of the rear surface of the liquid crystal display  310  and the nuts  370  are coupled with the two first fastening bolts  330 , respectively, thereby coupling the bracket  320  to the liquid crystal display  310  without movement. 
         [0068]    Further, the bracket  320  is coupled to the nuts  370  at opposite left and right sides of the rear surface of the liquid crystal display. That is, when the two brackets  320  are coupled to the liquid crystal display at opposite left and right sides of the liquid crystal display  310 , the second fastening bolts  340  are coupled to the main body of the system through second fastening holes  322  formed on the brackets, thereby coupling the liquid crystal display to the main body (not shown) of the system. 
         [0069]    As described above, the liquid crystal display according to the embodiments of the present invention has effects of simplifying the structure and reducing the material costs by removing guide pins. 
         [0070]    Further, the liquid crystal display according to the embodiments of the present invention has an effect of reducing a failure ratio by simplifying the structure. 
         [0071]    Further, the liquid crystal display according to the embodiments of the present invention has an effect of simplifying a process for fastening the liquid crystal display to the main body of the system by simplifying the structure. 
         [0072]    It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.