Patent Publication Number: US-RE47419-E

Title: Liquid crystal display device and electronic equipment having the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 12/952,126 filed on Nov. 22, 2010 and Ser. No. 13/237,938 filed on Sep. 21, 2011, the disclosures of each of which are incorporated herein by reference. 
     This application claims priority of Chinese Patent Application Nos. 201110081284.8 filed on Apr. 1, 2011; 201110116425.5 filed on May 6, 2011; and 201210079121.0 filed on Mar. 22, 2012, the disclosures of each of which are also incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The disclosure relates to a display device, more particularly to a frame structure of a liquid crystal display device and an electronic equipment having the liquid crystal display device. 
     2. Description of the Related Art 
     A currently available liquid crystal display module (LCM) includes a lower metal frame that accommodates therein a plastic frame, a backlight module disposed in the lower metal frame, and a liquid crystal display panel mounted on the plastic frame and disposed above the backlight module. Through an upper metal frame that is assembled to a periphery of the lower metal frame and that abuts against a top end of the liquid crystal display panel, the liquid crystal display panel can be stably positioned on the plastic frame. At this time, the assembly of the liquid crystal display module is completed. The liquid crystal display module is then sent to a system integrator where the liquid crystal display module is assembled between upper and lower casings. 
     However, this kind of liquid crystal display module has a complicated structure and involves many components, so that the assembly thereof is time-consuming and the manufacturing cost associated therewith is increased. 
     SUMMARY OF THE INVENTION 
     Therefore, an object of the present disclosure is to provide a liquid crystal display device having a one-piece frame structure that can minimize the number of components so that the structure thereof is simple, the assembly time can be reduced, the manufacturing cost associated therewith can be saved, and tolerances among the components can also be reduced. 
     The object of the present disclosure and the solution to the problem existing in the prior art can be realized by using the below technical means. According to the present disclosure, a liquid crystal display device comprises a support frame, a backlight module, and a liquid crystal display panel. 
     The support frame includes a bottom wall, and a main surrounding wall extending upwardly from and formed integrally as one piece with the bottom wall. The bottom wall and the surrounding wall cooperatively define a receiving space. The bottom wall includes a first support disposed in the receiving space. The main surrounding wall includes a second support disposed in the receiving space and spacedly above the first support. The backlight module is supported on the first support. The liquid crystal display panel is supported on the second support so that the liquid crystal display panel is positioned above the backlight module. 
     The object of the present disclosure and the solution to the problem existing in the prior art can be realized by using the below technical means. 
     Each of the first support and the second support has a horizontal support face. 
     The backlight module includes a light guide plate having a lateral side, and a light-emitting unit disposed on the lateral side. The main surrounding wall is recessed to form a cavity that is spacedly below the second support. The light-emitting unit is disposed in the cavity. 
     In an embodiment, the light guide plate further has a top side connected to a top end of the lateral side. The light-emitting unit includes a flexible circuit board, and a light-emitting diode disposed on a bottom side of the flexible circuit board and corresponding in position to the lateral side of the light guide plate. The liquid crystal display device further comprises an adhesive piece adhered to and disposed between the top side of the light guide plate and the flexible circuit board. 
     In another embodiment, the light guide plate further has a bottom side connected to a bottom end of the lateral side. The light-emitting unit includes a flexible circuit board abutting against the first support, and a light-emitting diode disposed on a top side of the flexible circuit board and corresponding in position to the lateral side of the light guide plate. The liquid crystal display device further comprises an adhesive piece adhered to and disposed between the bottom side of the light guide plate and the flexible circuit board. 
     In still another embodiment, the support frame is made by injection molding a plastic material. The light-emitting unit includes a flexible circuit board, and a light-emitting diode disposed on a top side of the flexible circuit board. The liquid crystal display device further comprises a metal frame disposed in the cavity and receiving clampingly the light-emitting unit and the light guide plate. 
     The metal frame is fixed to the support frame, and includes a vertical plate, a lower clamping plate extending horizontally and inwardly from a bottom end of the vertical plate, and an upper clamping plate extending horizontally and inwardly from a top end of the vertical plate. The lower clamping plate abuts against the first support and engages a bottom side of the flexible circuit board. The upper clamping plate engages a top end of the light-emitting diode and a top side of the light guide plate that is connected to a top end of the lateral side of the light guide plate so that the light-emitting diode is positioned at a location corresponding to the lateral side of the light guide plate. 
     The support frame is formed with an accommodation groove. The liquid crystal display device further comprises a control circuit board disposed in the accommodation groove, and a flexible transmission circuit connected electrically to the liquid crystal display panel and the control circuit board. 
     The bottom wall has a bottom face that is recessed to form the accommodation groove. The flexible transmission circuit is configured as a circuit band made by a chip on film (COF) technology. The flexible transmission circuit is bent downward and then inward extending around the support frame to connect with the control circuit board. 
     The main surrounding wall includes a left wall, a right wall, a front wall and a rear wall. The rear wall includes a positioning structure to position the backlight module. The positioning structure includes a positioning groove and a positioning stud provided in the positioning groove. The backlight module includes an optical film layer that has a projection engaged to the positioning groove and formed with a positioning hole for extension of the positioning stud therethrough. 
     The liquid crystal display device further comprises at least one double-sided adhesive tape adhering the liquid crystal display panel to one side of the second support. 
     The main surrounding wall includes a retention portion projecting from the other side of the second support to retain the liquid crystal display panel thereon. 
     The double-sided adhesive tape includes a pull portion exposed partially from the liquid crystal display panel, and two double-sided adhesive portions adhered to two opposite sides of the pull portion. The double-sided adhesive portions are further adhered to said one side of the second support and the liquid crystal display panel, respectively. 
     In another embodiment, the liquid crystal display device further comprises two the double-sided adhesive tapes to adhere the liquid crystal display panel to two opposite sides of the second support. 
     In still another embodiment, the main surrounding wall includes two retention portions projecting respectively from two opposite sides of the second support to retain the liquid crystal display panel thereon. 
     The liquid crystal display device further comprises an upper casing that covers a periphery of the liquid crystal display panel and that is formed with an opening to expose the liquid crystal display panel. 
     The support frame further includes an auxiliary surrounding wall extending upwardly from an outer periphery of the bottom wall and surrounding the main surrounding wall. The upper casing is connected to the auxiliary surrounding wall. 
     The support frame is made of a plastic material and includes two extension plates extending respectively from two opposite sides of the main surrounding wall. The liquid crystal display device further comprises a lower casing that is made of metal, that covers the support frame, and that is coupled to the upper casing, two coupling rods each disposed between the lower casing and a respective one of the extension plates, and two fasteners. Each of the fasteners fixes one of the coupling rods and the respective the extension plate to the lower casing. 
     The upper casing includes a first coupling portion. The liquid crystal display panel further includes a glass to cover the opening. The glass includes a second coupling portion coupled to the first coupling portion. 
     The first coupling portion is an inner periphery of the upper casing and defines the opening. The second coupling portion is configured as an annular groove to receive engagingly the inner periphery. 
     The main surrounding wall further includes a third support spacedly above the second support and having a horizontal support face. The liquid crystal display device further comprises a touch control panel supported on the third support. 
     Another object of the present disclosure is to provide an electronic equipment having a liquid crystal display device. The liquid crystal display device has a one-piece frame structure that can minimize number of components so that the structure thereof is simple, the assembly time can be reduced, the manufacturing cost associated therewith can be saved, and tolerances among the components can also be reduced. 
     According to another aspect of disclosure of the present disclosure, an electronic equipment comprises a lower casing, an electronic device, and a liquid crystal display device. 
     The lower casing defines a mounting space. The electronic device is disposed in the mounting space. The liquid crystal display device is disposed in the mounting space and is coupled electrically to the electronic device. The liquid crystal display device includes a support frame, a backlight module, a liquid crystal display panel, and a touch control panel. The support frame includes a bottom wall, and a main surrounding wall extending upwardly from and formed integrally as one piece with the bottom wall. The bottom wall and the surrounding wall cooperatively define a receiving space. The bottom wall includes a first support disposed in the receiving space. The main surrounding wall includes a second support disposed in the receiving space and spacedly above the first support, and a third support spacedly above the second support. The backlight module is supported on the first support. The liquid crystal display panel is supported on the second support. The touch control panel is supported on the third support. 
     Through the aforesaid technical means, the advantages and effects of the liquid crystal display device of this disclosure reside in that, through the first and second supports of the one-piece support frame that can accommodate respectively the backlight module and the liquid crystal display panel, the number of components of the liquid crystal display device can be reduced so that the structure thereof is simple, the assembly time can be reduced, the manufacturing cost associated therewith can be saved, and tolerances among the components can also be reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the present disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which: 
         FIG. 1  is a perspective view of a liquid crystal display device according to the first embodiment of the present disclosure; 
         FIG. 2  is a sectional view of the first embodiment taken along line II-II of  FIG. 1 , illustrating a backlight module and a liquid crystal display panel respectively supported on first and second supports of a support frame; 
         FIG. 3  is a schematic top view of the support frame of the first embodiment; 
         FIG. 4  is a sectional view of the first embodiment, illustrating an alternative form of an upper casing; 
         FIG. 5  is a fragmentary sectional view of the first embodiment taken along line V-V of  FIG. 1 ; 
         FIG. 6  is a fragmentary sectional view of a liquid crystal display device according to the second embodiment of the present disclosure; 
         FIG. 7  is a fragmentary sectional view of a liquid crystal display device according to the third embodiment of the present disclosure; 
         FIG. 8  is a perspective view of a liquid crystal display device according to the fourth embodiment of the present disclosure, illustrating how a glass is assembled to an upper casing; 
         FIG. 9  is a sectional view of the fourth embodiment, illustrating a first coupling portion of the upper casing is coupled to a second coupling portion of the glass; 
         FIG. 10  is a sectional view of a liquid crystal display device according to the fifth embodiment of the present disclosure, but without an upper casing; 
         FIG. 11  is a schematic top view of a support frame of the fifth embodiment; 
         FIG. 12  is another sectional view of the fifth embodiment, illustrating the upper casing being coupled to an outer surrounding wall of a lower casing; 
         FIG. 13  is a still another sectional view of the fifth embodiment, illustrating how each fastener fixes an extension plate and a coupling rod to a base plate of the lower casing; 
         FIG. 14  is a fragmentary sectional view of the fifth embodiment, illustrating a control circuit board being disposed in an accommodation groove of a bottom wall; 
         FIG. 15  is a sectional view of a liquid crystal display device according to the sixth embodiment of the present disclosure; 
         FIG. 16  is a schematic top view of a support frame of the sixth embodiment; 
         FIG. 17  is a view similar to  FIG. 16 , but illustrating how an optical film layer is connected to the support frame; 
         FIG. 18  is a sectional view of a liquid crystal display device according to the seventh embodiment of the present disclosure; 
         FIG. 19  is a schematic top view of a support frame of the seventh embodiment; 
         FIG. 20  is a fragmentary enlarged schematic view of the seventh embodiment, illustrating a double-sided adhesive tape adhered to and disposed between a liquid crystal display panel and a second support; 
         FIG. 21  is another sectional view of the seventh embodiment, illustrating the double-sided adhesive tape being removed the liquid crystal display panel and the second support; 
         FIG. 22  is still another sectional view of the seventh embodiment, illustrating an alternative form of the double-sided adhesive tape; 
         FIG. 23  is a sectional view of a liquid crystal display device according to the eighth embodiment of the present disclosure; 
         FIG. 24  is a sectional view of a liquid crystal display device according to the ninth embodiment of the present disclosure; 
         FIG. 25  is a sectional view of a liquid crystal display device according to the tenth embodiment of the present disclosure; and 
         FIG. 26  is a sectional view of an electronic equipment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The above-mentioned and other technical contents, features, and effects of this disclosure will be clearly presented from the following detailed description of ten embodiments in coordination with the reference drawings. Through description of the concrete implementation method, the technical means employed and the effectiveness to achieve the predetermined purposes of the present disclosure will be thoroughly and concretely understood. However, the enclosed drawings are used for reference and description only, and are not used for limiting the present disclosure. 
     Before this disclosure is described in detail, it should be noted that, in the following description, similar elements are designated by the same reference numerals. 
     Referring to  FIGS. 1 and 2 , a liquid crystal display device  100  according to the first embodiment of the present disclosure is adapted to be applied to a notebook computer as an example for illustration, and is shown to comprise a support frame  1 , a backlight module  2  and a liquid crystal display panel  3 . 
     As shown in  FIGS. 2 and 3 , the support frame  1  includes a bottom wall  11 , and a main surrounding wall  12  extending upwardly from and formed integrally as one piece with the bottom wall  11 . The bottom wall  11  and the main surrounding wall  12  cooperatively define a receiving space  13 . The bottom wall  11  includes a first support  111  disposed in the receiving space  13 . The main surrounding wall  12  includes a second support  121  disposed in the receiving space  13  and spacedly above the first support  111 . The backlight module  2  is supported on the first support  111 . The liquid crystal display panel  3  is supported on the second support  121  so that the liquid crystal display panel  3  is positioned above the backlight module  2 . Through the integrally formed one-piece support frame  1  that can accommodate simultaneously the backlight module  2  and the liquid crystal display panel  3 , the number of components of the liquid crystal display device  100  can be reduced so that the liquid crystal display device  100  has a simple structure. Because of this, the assembly time and the manufacturing costs thereof can be reduced. Further, accumulated tolerance of the components can also be reduced. 
     A detailed structure of the liquid crystal display device  100  will be described hereinbelow. 
     With reference to  FIGS. 2 and 3 , the backlight module  2  includes a reflective plate  21 , a light guide plate  22  stacked above the reflective plate  21 , and an optical film layer  23  stacked above the light guide plate  22 . The optical film layer  23  includes a lower diffusion plate, a first prism plate, a second prism plate, and an upper diffusion plate stacked one above the other. Since the function of each optical film of the optical film layer  23  is well known in the art, a detailed description thereof is dispensed herewith. Further, the assembly of the optical film layer  23  is not limited to the aforesaid disclosure. In this embodiment, the first support  111  is formed on a top face of the bottom wall  11 . The second support  121  is formed on and extends along the entire length of a top face of the main surrounding wall  12 . Each of the first and second supports  111 ,  121  has a horizontal support face. Because the reflective plate  21  abuts against the first support  111  and the liquid crystal display panel  3  abuts against the second support  121 , the backlight module  2  and the liquid crystal display panel  3  will not be slanting relative to the support frame when assembled thereon. Further, because the integrally formed one-piece support frame  1  can simultaneously accommodate the backlight module  2  and the liquid crystal display panel  3 , the accumulated tolerance among the components of the backlight module  2  and the liquid crystal display panel  3  can be reduced. 
     The support frame  1  is made by injection molding a plastic material. The main surrounding wall  12  further includes an annular projection  122  projecting upwardly from the second support  121 . The liquid crystal display device  100  further comprises a positioning element  4  in the form of a frame. The positioning element  4  covers the main surrounding wall  12 , and abuts against the projection  122  and the liquid crystal display panel  3 . The positioning element  4  is fixed to the projection  122  and the liquid crystal display panel  3  by using adhesive or a screw fastening method. Through this, the liquid crystal display panel  3  can be stably positioned to the main surrounding wall  12 . The positioning element  4  can be made of Mylar, aluminum foil, or metal. In this embodiment, the positioning element  4  is made of metal so as to provide an anti-EMI (anti-electromagnetic interference) effect. 
     The support frame  1  further includes an auxiliary surrounding wall  14  extending upwardly and integrally from an outer periphery of the bottom wall  11  and surrounding an outer periphery of the main surrounding wall  12 . The liquid crystal display device  100  further comprises an upper casing  5  covering a periphery of the liquid crystal display panel  3 . The upper casing  5  is made by injection molding a plastic material. The upper casing  5  has an upper wall  54  formed with an opening  51  for exposure of the liquid crystal display panel  3 , and an outer peripheral wall  52  extending downwardly from an outer periphery of the upper wall  54 . The outer peripheral wall  52  is connected to the auxiliary surrounding wall  14  by using a hook-and-groove interlocking means or a screw fastening method. Through such a connection, the upper casing  5  can be stably fixed to the support frame  1 . It should be noted that the upper casing  5  of this embodiment may be configured as that shown in  FIG. 4 . That is, the upper casing  5 ′ is formed integrally as one piece with the positioning element  4  shown in  FIG. 2 . The upper casing  5 ′ can similarly achieve the effect made by the upper casing  5  and the positioning element  4 . Thus, the number of components of the liquid crystal display device  100  can be further reduced. 
       FIG. 5  is a fragmentary sectional view of this embodiment taken along line V-V of  FIG. 1 . As shown in  FIG. 5 , the main surrounding wall  12  is recessed to form a cavity  123  that is spacedly below the second support  121 . The backlight module  2  further includes a light-emitting unit  24  disposed in the cavity  123  and supplying light to the light guide plate  22 . Concretely speaking, the light guide plate  22  has a lateral side  221 , and a top side  222  connected to a top end of the lateral side  221 . The light-emitting unit  24  includes a flexible circuit board  241  disposed on the top side  222  of the light guide plate  22 , and a light-emitting diode  242  disposed on a bottom side of the flexible circuit board  241  and corresponding in position to the lateral side  221  of the light guide plate  22 . Through this configuration, when the support frame  1  is deformed caused by an external force, the light-emitting unit  24  can be prevented from being displaced, so that light generated by the light-emitting diode  242  can be uniformly emitted to the light guide plate  22  through the lateral side  221  thereof. 
     Further, the liquid crystal display device further comprises an adhesive piece  61 . The adhesive piece  61  is configured as a double-sided adhesive tape adhered to and disposed between the top side  222  of the light guide plate  22  and the bottom side of the flexible circuit board  241 , so that the flexible circuit board  241  can be stably positioned to the top side  222  of the light guide plate  22 . 
     Referring to  FIG. 6 , a liquid crystal display device  110  according to the second embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, in this embodiment, the light guide plate  22  further has a bottom side  223  connected to a bottom end of the lateral side  221 , the flexible circuit board  241  abuts against the first support  111 , and the light-emitting diode  242  is disposed on a top side of the flexible circuit board  241  and corresponds in position to the lateral side  221  of the light guide plate  22 . The adhesive piece  61  is adhered to and disposed between the bottom side  223  of the light guide plate  22  and the top side of the flexible circuit board  241 , so that the light-emitting diode  242  can be stably positioned at a location corresponding to the lateral side  221  of the light guide plate  22 . 
     Referring to  FIG. 7 , a liquid crystal display device  120  according to the third embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, in this embodiment, because the support frame  1  is made by injection molding a plastic material so that the strength thereof is weak, to enhance the strength of the support frame  1 , a metal frame  62  is disposed in the cavity  123 , and receives clampingly the light-emitting unit  24  and the light guide plate  22 . Because the metal frame  62  can enhance the strength of the support frame  1  and protect the light-emitting unit  24 , when the support frame  1  is deformed caused by an external force, the light-emitting unit  24  can be prevented from being displaced. 
     Further, to enhance flatness of the first support  111  so that the light-emitting diode  242  cannot be slantingly disposed when assembled to the support frame  1 , the metal frame  62  is fixed to the support frame  1  by, for example, a screw fastening method. The metal frame  62  has a substantially U-shaped cross section, and includes a vertical plate  621 , a lower clamping plate  622  extending horizontally from a bottom end of the vertical plate  621 , and an upper clamping plate  623  extending horizontally from a top end of the vertical plate  621 . The lower clamping plate  622  abuts against the first support  111  and engages the bottom side of the flexible circuit board  241 . The upper clamping plate  623  engages a top end of the light-emitting diode  242  and the top side  222  of the light guide plate  22 . Through the upper and lower clamping plates  623 ,  622  that cooperatively clamp therebetween the light-emitting unit  24  and the light guide plate  22 , the light-emitting diode  242  can be positioned at a location corresponding to the lateral side  221  of the light guide plate  22 . Hence, light generated by the light-emitting diode  242  can be uniformly emitted to the light guide plate  22  through the lateral side  221  thereof. 
     Referring to  FIGS. 8 and 9 , a liquid crystal display device  130  according to the fourth embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, in this embodiment, the liquid crystal display device  130  further comprises a glass  7  to cover the opening  51 . The glass  7  is a tempered glass. 
     The upper casing  5  includes a first coupling portion  53 . The glass  7  includes a second coupling portion  71  coupled to the first coupling portion  53 . Through the interconnection of the first and second coupling portions  53 ,  71 , the glass  7  can be fixed to the upper casing  5  so as to cover the opening  51 . In this embodiment, the first coupling portion  53  is an inner periphery of the upper wall  54  and defines the opening  51 . The second coupling portion  71  is configured as an annular groove that extends inwardly from an outer peripheral face  70  of the glass  7  and receiving engagingly the inner periphery or the first coupling portion  53 . The connection between the first and second coupling portions  53 ,  71  can be accomplished using the below two methods. 
     In the first method, the glass  7  is cooled to shrink its volume, after which the glass  7  is brought to a working environment having a room temperature. The glass  7  is then inserted into the opening  51  of the upper casing  5  aligning the second coupling portion  71  with the first coupling portion  53 . After the glass  7  is placed at room temperature for a period of time, the glass  7  will return to a room temperature condition and the volume thereof will expand. Hence, the second coupling portion  71  is coupled fixedly to the first coupling portion  53 . 
     In the second method, the upper casing  5  is heated to expand its volume, after which the upper casing  5  is brought to a working environment having a room temperature. The glass  7  is then inserted into the opening  51  of the upper casing  5  aligning the second coupling portion  71  with the first coupling portion  53 . After the upper casing  5  is placed at room temperature for a period of time, the upper casing  5  will return to a room temperature condition and the volume thereof will shrink. Hence, the second coupling portion  71  is coupled fixedly to the first coupling portion  53 . 
     In both methods, because the second coupling portion  71  can be coupled fixedly to the first coupling portion  53 , the glass  7  can be assembled fixedly and stably to the upper casing  5 . Hence, the structural strength of the upper casing  5  can be enhanced. Moreover, the glass  7  can be configured to partly or fully cover the upper wall  54 , so that the liquid crystal display device  130  can exhibit a frameless visual effect. It should be noted that the connection between the first and second coupling portions  53 ,  71  is not limited to the aforesaid disclosures. 
     Referring to  FIGS. 10, 11 and 12 , a liquid crystal display device  140  according to the fifth embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, in this embodiment, the main surrounding wall  12  of the support frame  1  includes a left wall  124 , a right wall  125 , a front wall  126  connected to front ends of the left and right walls  124 ,  125 , and a rear wall  127  connected to rear ends of the left and right walls  124 ,  125 . The support frame  1  further includes two elongated extension plates  15  extending respectively and outwardly from outer sides of the left and right walls  124 ,  125 . The liquid crystal display device  140  further comprises a lower casing  63 , two coupling rods  64 , and two fasteners  65 . The lower casing  63  covers a bottom side of the support frame  1 , and is coupled to the upper casing  5 . In this embodiment, the upper casing  5  and the lower casing  63  are made of metal. An outer peripheral wall  631  of the lower casing  63  and the outer peripheral wall  52  of the upper casing  5  are coupled fixedly to each other by using a hook-and-groove interlocking means or a screw fastening method. However, the connection between the outer peripheral walls  631 ,  52  is not limited to the aforesaid disclosures. 
     The two coupling rods  64  are made of metal and are connected respectively to two hinges (not shown) of the notebook computer. The hinges are disposed in a system housing (not shown) of the notebook computer, so that the liquid crystal display device  140  can rotate relative to the system housing through the hinges. Each of the coupling rods  64  is elongated, and is disposed between a base plate  632  of the lower casing  63  and a respective extension plate  15 . Each fastener  65  is configured as a screw that extends through one of the extension plates  15  and the respective coupling rod  64  and that engages threadedly the base plate  632 , so that each extension plate  15  and the respective coupling rod  64  are fixed to the base plate  632 . By fixing the coupling rods  64  between the base plate  632  and the respective extension plates  15 , the structural strength among the hinges, the support frame  1  and the lower casing  63  can be enhanced. Hence, the liquid crystal display device  140  can rotate smoothly relative to the system housing through the hinges. Further, as shown in  FIG. 13 , the base plate  632  of the lower casing  63  can be provided with two internally threaded studs  633 , so that the screws or fasteners  65  can be threaded respectively to threaded holes (not shown) in the studs  633 . In this case, there is no need to form threaded holes in the base plate  632  for threaded engagement with the fasteners  65 . The internally threaded studs  633  can be formed with deeper threaded holes so as to enhance the fastening strength of the fasteners  65  when the fasteners  65  are engaged to the studs  633 . 
     As shown in  FIG. 14 , which is a fragmentary sectional side view of the liquid crystal display device  140 , to effectively reduce the width of the upper wall  54  of the upper casing  5  so that the liquid crystal display device  140  has a narrow upper frame, the below structural design is employed. 
     The support frame  1  is formed with an accommodation groove  112 . The liquid crystal display device  140  further comprises a control circuit board  66  disposed in the accommodation groove  112 , and a flexible transmission circuit  67  connected electrically to the liquid crystal display panel  3  and the control circuit board  66 . Through the presence of the accommodation groove  112  that accommodates the control circuit board  66 , the control circuit board  66  and the flexible transmission circuit  67  can be disposed between the upper casing  5  and the lower casing  63 . Either the upper casing  5  or the lower casing  63  does not need an additional structure to receive the control circuit board  66 . Hence, the width of the upper wall  54  can be reduced, and the liquid crystal display device  140  can have a narrow upper frame. 
     Concretely speaking, the bottom wall  11  of the support frame  1  has a bottom face  113  that is recessed to form the accommodation groove  112 , so that the control circuit board  66  can be received inside the bottom wall  11 . The flexible transmission circuit  67  is configured as a circuit band made by a chip on film (COF) technology and transmitting a control signal generated by the control circuit board  66  to the liquid crystal display panel  3 . The flexible transmission circuit  67  is bent downward and then inward extending around the support frame  1  to connect with the control circuit board  66 . Through this, the flexible transmission circuit  67  can be positioned between the support frame  1  and the positioning element  4 . 
     Referring to  FIGS. 15 to 17 , a liquid crystal display device  150  according to the sixth embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, to effectively reduce the width of the upper wall  54  of the upper casing  5  so that the liquid crystal display device  150  can have a narrow upper frame, the liquid crystal display device  150  of this embodiment can be realized through the below structural design. 
     In this embodiment, the rear wall  127  of the main surrounding wall  12  includes two positioning structures  128  spaced apart in a left-right direction to position the backlight module  2  so that the backlight module  2  is assembled to the support frame  1  in a correct direction of assembly. Further, the positioning structures  128  can position the backlight module  2  in the receiving space  13 . 
     Concretely speaking, each of the positioning structures  128  includes a positioning groove  131  and a positioning stud  132  provided in the positioning groove  131 . The optical film layer  23  of the backlight module  2  includes two projections  231  each having a shape matching that of the positioning groove  131  so as to engage with the same. Each of the projections  231  is formed with a positioning hole  232  having a shape matching that of the positioning stud  132 . When each projection  231  engages the respective positioning groove  131 , the positioning stud  132  of each positioning structure  128  extends into the positioning hole  232  of the respective projection  231  simultaneously, so that the optical film layer  23  of the backlight module  2  can be stably positioned in the receiving space  13  and will not rocked. By providing the positioning structures  128  on the rear wall  127  of the main surrounding wall  12 , the size of the left and right sides of each of the support frame  1  and the upper wall  54  of the upper casing  5  can be effectively reduced. For example, as shown in  FIG. 16 , a gap between the right wall  125  and the auxiliary surrounding wall  14  can be omitted, so that the liquid crystal display device  150  can have a narrow frame. 
     Referring to  FIGS. 18 to 20 , a liquid crystal display device  160  according to the seventh embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, to effectively reduce the width of the upper wall  54  of the upper casing  5  so that the liquid crystal display device  160  can have a narrow upper frame, the liquid crystal display device  160  of this embodiment can be realized through the below structural design. 
     In this embodiment, the liquid crystal display device  160  further comprises a double-sided adhesive tape  68  adhering the liquid crystal display panel  3  to one side of the second support  121 . The main surrounding wall  12  further includes a retention portion  129  projecting from the other side of the second support  121 . The double-sided adhesive tape  68  and the retention portion  129  are opposite to each other. When the liquid crystal display panel  3  is assembled on the support frame  1 , the liquid crystal display panel  3  is placed on the second support  121  such that the double-sided adhesive tape  68  adheres one side of the liquid crystal display panel  3  and the retention portion  129  retains the other side of the liquid crystal display panel  3  in a retention hole  10  (see  FIG. 18 ) defined by the retention portion  129  and the second support  121 . Hence, the liquid crystal display panel  3  can be fixed stably on the second support  121  of the support frame  1 . Through the aforesaid configuration, the positioning element  4  shown in  FIG. 2  can be dispensed herewith, and the support frame  1  can omit a space for receiving the positioning element  4 . Hence, the width of each of the support frame  1  and the upper wall  54  of the upper casing  5  can be effectively reduced, so that the liquid crystal display device  160  can have a narrow frame. 
     With reference to  FIGS. 19 to 21 , further, in considering rework for the liquid crystal display device  160 , in this embodiment, the double-sided adhesive tape  68  includes a pull portion  681 , and two double-sided adhesive tape portions  682  adhered respectively to two opposite sides of the pull portion  681 . The pull portion  681  is made of PET material. The double-sided adhesive tape portions  682  are further adhered to the second support  112  at one side of the main surrounding wall  12  and the liquid crystal display panel  3 , respectively. One end of the pull portion  681  is exposed from one side of the liquid crystal display panel  3 , as best shown in  FIG. 19 . When it is desired to disassemble the liquid crystal display device  160  for a rework operation, the upper casing  5  is first removed from the support frame  1 . Afterwards, the exposed end of the pull portion  681  is pulled out in the direction of an arrow shown in  FIG. 19  so as to separate the double-sided adhesive tape portions  682  from the second support  112  and the liquid crystal display panel  3 , respectively. Subsequently, the liquid crystal display panel  3  can be disengaged from the retention portion  129 . Because disassembly is very simple and convenient, the time of disassembly can be shortened. 
     Alternatively, as shown in  FIG. 22 , the width of the double-sided adhesive tape  68  can be enlarged so that the double-sided adhesive tape  68  can be adhered to an outer wall face of the main surrounding wall  12 , the bottom wall  11 , and a signal transmission wire  69 , simultaneously. 
     Referring to  FIG. 23 , a liquid crystal display device  170  according to the eighth embodiment of this disclosure has an overall structure similar to that of the seventh embodiment. However, in this embodiment, the liquid crystal display device  170  comprises two double-sided adhesive tapes  68  to adhere the liquid crystal display panel  3  to two opposite sides of the second support  121 . Hence, the liquid crystal display panel  3  can be stably adhered to the second support  121  of the support frame  1 . 
     Referring to  FIG. 24 , a liquid crystal display device  180  according to the ninth embodiment of this disclosure has an overall structure similar to that of the seventh embodiment. However, in this embodiment, the main surrounding wall  12  further includes two retention portions  129  projecting respectively from two opposite sides of the second support  121  to retain two opposite sides of the liquid crystal display panel  3  in the retention holes  10 . Similarly, the liquid crystal display panel  3  can be positioned stably on the second support  121  of the support frame  1 . 
     Referring to  FIG. 25 , a liquid crystal display device  190  according to the tenth embodiment of this disclosure has an overall structure similar to that of the first embodiment. However, in this embodiment, the main surrounding wall  12  of the support frame  1  further includes a third support  133  spacedly above the second support  112  and having a horizontal support face. The liquid crystal display device  190  further includes a touch control panel  8  supported on the third support  133 . In this embodiment, the touch control panel  8  is a capacitive touch control panel that is adhered fixedly to the third support  133  by using glue or double-sided adhesive tape so as to be positioned stably above the liquid crystal display panel  3 . Because the liquid crystal display panel  3  and the touch control panel  8  are respectively positioned on the second and third supports  121 ,  133  of the support frame  1 , accuracy of assembly between the liquid crystal display panel  3  and the touch control panel  8  can be enhanced, and the accumulated tolerance of the components can be reduced. 
     Referring to  FIG. 26 , the liquid crystal display device  190  is applied in an electronic equipment  200 , such as a tablet computer. In this case, a lower casing  63  having a mounting space  634  is provided. The electronic equipment has an electronic device  9  disposed in the mounting space  634 . The electronic device  9  includes a motherboard, a hard disk, a battery, and other essential electronic components for providing normal operation of the electronic equipment  200 . The liquid crystal display device  190  is disposed in the mounting space  634  such that the bottom wall  11  of the support frame  1  is located above the electronic device  9 . An outer peripheral wall  631  of the lower casing  63  surrounds an outer periphery of the main surrounding wall  12  of the support frame  1 , and abuts against the support frame  1 . The outer peripheral wall  631  and the main surrounding wall  12  may be interconnected to each other such as by using a hook-and-groove interlocking means or a screw fastening means. The center of the bottom wall  11  is formed with a through hole  114  in spatial communication with the receiving space  13 . The electronic device  9  can transmit power and signals to the backlight module  2 , the liquid crystal display panel  3  and the touch control panel  8  of the liquid crystal display device  190  by using a cable (not shown) that extends through the through hole  114 . By embodying the liquid crystal display device  190  of this disclosure, the number of components of the electronic equipment  200  can be reduced, so that the assembly time and the manufacturing costs thereof can be saved. It should be noted that the connection between the outer peripheral wall  631  and the main surrounding wall  12  is not limited to the aforesaid disclosures. 
     In summary, the liquid crystal display device  100 - 190  of each of the embodiments uses the first and second supports  111 ,  121  of the integrally formed support frame  1  to support the backlight module  2  and the liquid crystal display panel  3 , respectively, so that the number of components of the liquid crystal display device  100 - 190  can be reduced and the structure of the liquid crystal display device  100 - 190  simple. Further, the assembly time can be shortened, the manufacturing costs can be saved, and the accumulated tolerance of the components can be reduced. Hence, the objects of this disclosure can be realized. 
     While the present disclosure has been described in connection with what are considered the most practical embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.