KR20060078873A - A backlight assemlby improving a structure for a ground contact of an inverter and a flat display device provided with the same - Google Patents

Abstract

The present invention relates to a backlight assembly having an improved inverter grounding structure and a flat panel display device having the same. To this end, the backlight assembly according to the present invention includes a light source for supplying light, an inverter for applying a driving voltage to the light source, a shield case covering and protecting the inverter, and a ground wire connected to and grounded to the inverter. Here, the washer connected to one end of the ground wire is screwed together with a screw hole formed in the inverter and the shield case, the side of the washer is fixed adjacent to the shield case.

Inverter, Ground Wire, Washer, Screw, Shield Case

Description

BACKLIGHT ASSEMLBY IMPROVING A STRUCTURE FOR A GROUND CONTACT OF AN INVERTER AND A FLAT DISPLAY DEVICE PROVIDED WITH THE SAME}

1 is an exploded perspective view of a backlight assembly according to an embodiment of the present invention.

2 is a rear perspective view of the backlight assembly according to an exemplary embodiment of the present invention.

3 is an exploded perspective view of a flat panel display device according to an exemplary embodiment of the present invention.

The present invention relates to a backlight assembly having an improved inverter grounding structure and a flat panel display device having the same, and more particularly, to a backlight assembly having an improved inverter grounding structure using a washer and a flat panel display having the same. Relates to a device.

With the recent rapid development of semiconductor technology, the demand for liquid crystal display devices having improved performance while being smaller and lighter is exploding.

Recently, liquid crystal displays (LCDs), which have been in the spotlight, have advantages such as miniaturization, light weight, and low power consumption, and as an alternative means to overcome the disadvantages of the conventional cathode ray tube (CRT). It has been attracting attention gradually and is currently used in almost all information processing devices that require a display device.

A general liquid crystal display device applies voltage to a specific molecular array of a liquid crystal to convert it into another molecular array, and visually changes optical properties such as birefringence, photoreactivity, dichroism, and light scattering characteristics of the liquid crystal cell emitted by the molecular array. It is a light-receiving display device which converts into a change and displays information using the modulation of the light by a liquid crystal cell.

Since the liquid crystal display is a light receiving display device, a backlight assembly for supplying light is required to display an image. The backlight assembly includes a light source that emits light. Typically, the backlight assembly uses an inverter to convert power supplied from the outside into a constant voltage and then apply the light to the light source.

The inverter attaches to the back of the backlight assembly and protects by covering a shield case on top. The inverter is grounded using a separate external ground wire to prevent electromagnetic interference (EMI) and electrostatic discharge (ESD). The ground wire is screwed between the inverter board and the shield case to ground the inverter board.

The inverter board is formed with a guide member to fix the ground wire to the ground wire to facilitate the external connection of the ground wire. However, when the guide member is separately formed on the inverter board, the cost due to the addition of parts is increased, and there is a problem in that the grounding wire falls out of the guide member well even when the guide member is formed. In addition, as the ground wire flows, the screw fixing the ground wire is loosened, thereby causing a problem in that the fastening state of the inverter and the shield case is released.

Since the reliability of the connection between the inverter board and the ground wire is lowered, the grounding state of the inverter board is poor, and many problems occur such that the inverter board malfunctions due to EMI and ESD.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a backlight assembly having an improved grounding structure by effectively connecting a ground line to an inverter.

In addition, the present invention is to provide a flat panel display device having the above-described backlight assembly.

The backlight assembly according to the present invention for achieving the above object, a light source for supplying light, an inverter for applying a driving voltage to the light source, a shield case for covering and protecting the inverter, and connected to the inverter to ground It includes a ground wire. Here, the washer connected to one end of the ground wire is screwed together with a screw hole formed in the inverter and the shield case, the side of the washer is fixed adjacent to the shield case.

The shield case includes a cover part spaced apart from the inverter to cover the inverter, a support part bent from a part of the edge of the cover part and extended toward the inverter, and a fixing part bent while being connected to the support part and screwed to the inverter.

The washer may be fixed on the fixing portion of the shield case.

The washer is preferably fixed to the side of the support portion of the shield case adjacent.

The side of the washer preferably extends in a straight line.

The washer is preferably in the form of a polygon.

More preferably, the washer has a rectangular shape.

A flat panel display device according to the present invention includes a flat panel display panel for displaying an image, and the aforementioned backlight assembly for supplying light to the flat panel display panel.

Here, the flat panel display panel may be a liquid crystal display panel.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 3. These embodiments of the present invention are merely for illustrating the present invention, but the present invention is not limited thereto.

1 is an exploded perspective view of a backlight assembly 70 according to an embodiment of the present invention, which shows a backlight assembly 70 in which a plurality of light sources 76 are arranged side by side. The structure of the backlight assembly 70 shown in FIG. 1 is merely for illustrating the present invention, but the present invention is not limited thereto. Therefore, the present invention can also be applied to backlight assemblies having other structures.

The backlight assembly 70 is formed by combining an optical sheet 72, a diffusion plate 74, a light source 76, a frame mold side 78, and the like and emits light emitted from the light source 76. Diffuses to make it uniform and emits in the Z-axis direction. The bottom chassis 75 located below the backlight assembly 70 houses internal components including a light source 76 and a frame mold side 78, and a mold frame 71 located above the bottom chassis 75. It is fixedly coupled on a bottom chassis 75.

A plurality of light sources 76 for supplying light are arranged to be fixedly spaced apart from the bottom chassis 75 by a predetermined distance, and the reflective sheet 79 is installed on the bottom surface of the bottom chassis 75 so as to provide a light source 76. Reflect light emitted from the Although an lamp is shown as an example of the light source 76 in FIG. 1, this is merely to illustrate the present invention, and the present invention is not limited thereto. Therefore, a light emitting diode (LED) may be used in addition to the lamp, and a light source having a linear light source or a surface light source may be used.

A light source holder (not shown) is provided at an end of the light source 76 to fix and support the light source 76. The light source holder (not shown) is covered with the frame mold side 78 extending in the Y-axis direction.

Light emitted from the plurality of light sources 76 is evenly spread through the diffusion plate 74. This makes it possible to distribute the light more uniformly. Then, the brightness of the light is improved and supplied to the upper part through the optical sheet 72 positioned on the diffusion plate 74. Accordingly, it is possible to supply light with uniformity and improved brightness.

The back of the bottom chassis 75 is provided with an inverter 73 for applying a driving voltage to the light source 76, and covered with a shield case 77 to protect. The light source 76 is connected to the inverter 73 through a wire (not shown) connected to the light source 76, and the inverter 73 applies a driving voltage to the light source 76.

A separate ground line 10 (shown in FIG. 2) is connected to the inverter 73 to thereby ground the inverter 73. Hereinafter, the externally connected ground line 10 will be described in more detail with reference to FIG. 2.

FIG. 2 is a rear perspective view of the backlight assembly 70 according to an embodiment of the present invention, in which all internal components of the backlight assembly 70 shown in FIG. 1 are combined, and then rotated 180 ° about the X axis. . The enlarged source of FIG. 2 enlarges and shows the fastening state of the washer 101, the shield case 77, and the inverter 73. As shown in FIG.

As shown in FIG. 2, the ground wire 10 connected to the inverter 73 is temporarily fixed by attaching the tape 14 to the bottom chassis 75. The ground line 10 temporarily fixed in this manner is externally connected at the time of being stored in an external set to ground the inverter 73. Accordingly, EMI and ESD generated by the inverter 73 can be significantly reduced to prevent malfunction.

The washer 101 is connected to one end of the ground wire 10, and the connector 103 is connected to the other end. The washer 101 is fastened together to the screw hole 731 formed in the inverter 73 and the screw hole 7775 formed in the shield case 77. That is, the washer 101, the shield case 77 and the inverter 73 are sequentially placed from the top to the bottom, and are fastened and fixed to the bottom chassis 75 with screws 12. In the washer 101 attachment position, the washer 101, the shield case 77, and the inverter 73 are in close contact with each other, so that the washer 101 and the inverter 73 can be electrically energized. Accordingly, the reliability of the inverter 73 ground can be secured.

The shield case 77 includes a cover 771, a support 773, and a fixing part 775. The cover part 771 of the shield case 77 is spaced apart from the inverter 73 in the Z-axis direction to cover the inverter 73. As a result, the inverter 73 can be protected from external shock. The support part 773 of the shield case 77 is bent from a part of the edge of the cover part 771 and extends toward the inverter 73 side. Accordingly, the cover unit 771 of the shield case 77 and the inverter 73 can be separated from each other to protect the inverter 73 from external shock. The fixing part 775 is bent while being connected to the support part 773 and screwed to the inverter 73. For this purpose, the fixing part 775 is in close contact with the inverter 73.

The washer 101 is fixed on the fixing part 775 of the shield case 77. Accordingly, the washer 101 is easily detached. On the other hand, the washer 101 has its side surface 1011 fixed adjacent to the shield case 77. More specifically, the side surface 1011 is fixed adjacent to the support 773 of the shield case 77. Since the side surface 1011 of the washer 101 extends in a straight line and is fixed to the support part 773 of the shield case 77, the washer 101 does not flow. Accordingly, the fastening state of the washer 101 can be kept fairly firm.

As described above, when the shape of the washer 101 is a polygon, it is advantageous to fix the shield case 77 because the side surface is formed in a straight line. When the washer 101 is a general circular shape, the side is formed in a curved shape so that the flow occurs easily, so that the screw is loosened and falls out well. On the other hand, if the washer 101 is formed in a polygonal shape, the side of the washer 101 is fixed adjacent to the shield case 77 can prevent the flow of the washer 101. Accordingly, the screw fastening state is continuously maintained to ensure the reliability of the ground of the inverter 73. In addition, the structure does not require the use of a separate fixing member to support the ground wire 10.

On the other hand, in the enlarged circle of Figure 2 is shown a washer 101 in the form of a square, which is merely to illustrate the present invention, the present invention is not limited thereto. Therefore, the washer 101 may be formed in another polygonal shape.

3 is an exploded perspective view of a flat panel display device 100 having a backlight assembly 70 according to an embodiment of the present invention, and shows a state in which the liquid crystal display panel 50 is coupled to the backlight assembly 70.

3 illustrates the liquid crystal display panel 50 as an example of a flat panel display panel, this is merely to illustrate the present invention and the present invention is not limited thereto. Accordingly, other types of light receiving flat panel display panels may be used. In FIG. 3, the liquid crystal display panel 50 disposed on the backlight assembly 70 is assembled with the backlight assembly 70 while covering the liquid crystal display panel 50 with the top chassis 60 to manufacture the flat panel display device 100.

The liquid crystal display panel assembly 40 includes a liquid crystal display panel 50, a COF (chip on film) 43, 44, and a printed circuit board 41, 42, etc. connected thereto to supply a driving signal. It includes. The printed circuit boards 41 and 42 may be accommodated in the side surface of the top chassis 60.

The liquid crystal display panel 50 includes a TFT substrate 51 composed of a plurality of TFTs (thin film transistors), a color filter substrate 53 positioned on the TFT substrate 51, and a liquid crystal (injected therebetween). Not shown). Polarizing plates are attached to the upper portion of the color filter substrate 53 and the lower portion of the TFT substrate 51 to polarize light passing through the liquid crystal display panel 50.

The TFT substrate 51 is a transparent glass substrate on which a matrix thin film transistor is formed, a data line is connected to a source terminal, and a gate line is connected to a gate terminal. In the drain terminal, a pixel electrode made of transparent indium tin oxide (ITO) as a conductive material is formed.

When electrical signals are input from the printed circuit boards 41 and 42 to the gate lines and the data lines of the liquid crystal display panel 50 described above, electrical signals are input to the gate terminal and the source terminal of the TFT, and these electrical signals are input. According to the input of the TFT, the TFT is turned on or turned off so that an electrical signal necessary for pixel formation is output to the drain terminal.

On the other hand, the color filter substrate 53 is disposed thereon opposite the TFT substrate 51. The color filter substrate 53 is a substrate in which RGB pixels, which are color pixels in which a predetermined color is expressed while light passes, are formed by a thin film process, and a common electrode made of ITO is coated on the entire surface thereof. When power is applied to the gate terminal and the source terminal of the TFT and the thin film transistor is turned on, an electric field is formed between the pixel electrode and the common electrode of the color filter substrate. By this electric field, the arrangement angle of the liquid crystal injected between the TFT substrate 51 and the color filter substrate 53 is changed, and the light transmittance is changed according to the changed arrangement angle to obtain a desired pixel.

The printed circuit boards 41 and 42 for receiving image signals from the outside of the liquid crystal display panel 50 and applying driving signals to the gate lines and the data lines, respectively, are respectively attached to the COFs 43 attached to the liquid crystal display panel 50. , 44). In order to drive the flat panel display device 100, the gate side printed circuit board 41 transmits a gate driving signal, and the data side printed circuit board 42 transmits a data driving signal. That is, the gate driving signal and the data driving signal are applied to the gate line and the data line of the liquid crystal display panel 50 through the respective COFs 43 and 44 on which the integrated circuit chips 431 and 441 are mounted. A control board (not shown) is installed on the back of the backlight assembly 70. The control board is connected to the data side printed circuit board 42 to convert an analog data signal into a digital data signal and then supplies the same to the liquid crystal display panel 50.

The top chassis 60 for preventing the liquid crystal display panel assembly 40 from escaping from the backlight assembly 70 while bending the COFs 43 and 44 to the side of the backlight assembly 70 on the liquid crystal display panel assembly 40. It is provided. Although not shown in FIG. 1, the front case and the rear case are positioned at the top of the top chassis 60 and the bottom of the bottom chassis 75, respectively, to form the flat panel display device 100 by combining them.

As described above, in the backlight assembly according to the present invention, since the washer connected to one end of the ground wire is fixed adjacent to the side of the shield case, the washer does not move, so that the fastening structure is firm. Accordingly, there is an advantage that the ground state of the ground wire connected to the inverter is firm, thereby ensuring reliability of the ground of the inverter.

In addition, since the shield case includes a cover part, a support part, and a fixing part, the inverter can be protected from external shock.                     

And because the washer is fixed on the fixed portion of the shield case, there is an advantage that can prevent the flow due to the shield case.

Since the side of the washer is fixed adjacent to the support portion of the shield case, there is an advantage that the screw fastening state is firm and does not require a separate fixing member for supporting the ground wire.

Since the side of the washer extends in a straight line and is fixed, the screw is not easily moved even when the screw is fastened.

Since the washer has a polygonal shape, it is easy to process and easy to screw with the shield case.

Here, the washer is more preferably in the form of a square, in which case the washer is easy to process.

Since the flat panel display according to the present invention includes the above-described backlight assembly, the grounding state of the inverter is good, there is an advantage that can prevent the malfunction of the flat panel display.

Here, since the flat panel display panel is a liquid crystal display panel, the application possibility is high.

Although the present invention has been described above, it will be readily understood by those skilled in the art that various modifications and variations are possible without departing from the spirit and scope of the claims set out below.

Claims (9)

Light source for supplying light, An inverter for applying a driving voltage to the light source, A shield case covering and protecting the inverter, and A ground wire connected to the inverter to ground the inverter Including, A washer connected to one end of the ground wire is screwed together to a screw hole formed in the inverter and the shield case, and the washer is a backlight assembly whose side is adjacently fixed to the shield case. In claim 1, The shield case, A cover part spaced apart from the inverter to cover the inverter, A support portion bent from a portion of an edge of the cover portion and extended toward the inverter side; and Fixed part bent while being connected to the support and screwed to the inverter Backlight assembly comprising a. And the washer is fixed on the fixing part of the shield case. In claim 3, And the washer has its side fixed to the support. In claim 4, The side of the washer extends in a straight line form the backlight assembly. In claim 4, The washer is a polygonal backlight assembly. In claim 6, The washer is a backlight assembly. A flat panel display panel displaying an image, and The backlight assembly of claim 1, wherein the backlight assembly supplies light to the flat panel display panel. Flat display device comprising a. In claim 8, And the flat panel display panel is a liquid crystal display panel.

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