KR100966432B1 - Liquid crystal display device improving ground method of printed circuit board - Google Patents

Abstract

The liquid crystal display device of the present invention improves the grounding method of a printed circuit board by using a single-sided mounting ground means, the liquid crystal display panel comprising an array substrate and a color filter substrate; A backlight unit disposed under the liquid crystal display panel; A driving circuit unit electrically connected to the array substrate and including a printed circuit board having at least one opening; A case including an upper case fixing the liquid crystal display panel, the driving circuit unit, and the backlight unit; And at least one grounding means divided into a first connecting portion electrically connected to the printed circuit board and a second connecting portion contacting the upper case, wherein the second connecting portion of the grounding means is opened through an opening of the printed circuit board. It protrudes and contacts the upper case.

Printed Circuit Boards, Grounding Means, Electromagnetic Interference, Noise

Description

Liquid Crystal Display Improved the Grounding Method of Printed Circuit Boards {LIQUID CRYSTAL DISPLAY DEVICE IMPROVING GROUND METHOD OF PRINTED CIRCUIT BOARD}

1 is an exploded perspective view schematically showing a general liquid crystal display device.

FIG. 2 is a partial cross-sectional view taken along line II-II 'of the liquid crystal display shown in FIG. 1;

3 is a partial cross-sectional view showing a liquid crystal display device according to a first embodiment of the present invention.

4 is a partial cross-sectional view showing a liquid crystal display device according to a second embodiment of the present invention.

5A and 5B are enlarged perspective views of the grounding means of the LCD shown in FIG. 4.

*** Explanation of symbols for the main parts of the drawing ***

31,131,231: upper case 41,141,241: printed circuit board

170,270,270: grounding means 271,271: first connection portion

272,272a: second connection portion 273: opening

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device including a grounding means for improving the grounding method of a printed circuit board.

Recently, with increasing interest in information display and increasing demand for using a portable information carrier, a lightweight flat panel display (FPD), which replaces a conventional display device, a cathode ray tube (CRT), is used. The research and commercialization of Korea is focused on. In particular, the liquid crystal display (LCD) of the flat panel display device is an image representing the image using the optical anisotropy of the liquid crystal, is excellent in resolution, color display and image quality, and is actively applied to notebooks or desktop monitors have.

1 is an exploded perspective view schematically illustrating a general liquid crystal display.

As shown in the drawing, the liquid crystal display device includes a liquid crystal display panel 10 including a driving circuit unit 40 to output an image and a rear surface of the liquid crystal display panel 10. The backlight unit 20 emits light over the entire surface of the 10, and the case 30 accommodates and fixes the liquid crystal display panel 10 and the backlight unit 20.

The liquid crystal display panel 10 includes an array substrate 11 and a color filter substrate 12 and a liquid crystal layer (not shown) injected between the array substrate 11 and the color filter substrate 12. The driving circuit unit 40 may include various elements such as a timing controller for driving the liquid crystal display panel 10 and a tape carrier package (TCP) ( 42 is composed of a printed circuit board (PCB) 41 attached thereto.

There are two types of tape-carrier-packages: data tape-carrier-package and gate tape-carrier-package. The data tape-carrier-package is equipped with a data driver integrated circuit (IC) and a gate tape- The carrier-package includes a gate driver integrated circuit.

The backlight unit 20 includes a lamp assembly (not shown) including a fluorescent lamp for emitting light, a reflection sheet 21 for reflecting light emitted from the fluorescent lamp, and a light guide plate for guiding light. (light guide plate) 22, is provided on the upper surface of the light guide plate 22 is composed of a plurality of optical sheets 23 and the like to diffuse and collect the light transmitted from the light guide plate (22).

In addition, the case 30 sequentially rotates the upper case 31, the lower case 32, the reflecting plate 21, the light guide plate 22, the optical sheet 23, and the lamp assembly to fix and protect the LCD. It consists of a mold frame 32 for receiving.

In such a liquid crystal display device, in order to enlarge an image display area in which an image is displayed on a liquid crystal display panel, a data printed circuit board having a data tape-carrier-package is generally bent and placed at the back of the backlight, and a gate tape-carrier is provided. The package is bent to the side of the mold frame (hereinafter referred to as a half-folding shape), and the details are as follows.

FIG. 2 is a partial cross-sectional view taken along the line II-II 'of the liquid crystal display shown in FIG. 1 and shows a gate tape-carrier-package having a semi-bent shape.                         

As shown in the drawing, a backlight unit 20 including a reflector 21, a light guide plate 22, and an optical sheet 23 is positioned on the lower case 32, and an array substrate is disposed on the backlight unit 20. 11) and the color filter substrate 12 are positioned in this order. In this case, the mold frame 33 is positioned at the side of the backlight unit 20 to store and support the backlight unit 20 together with the lower case 32.

In addition, the printed circuit board 41 connected to the array substrate 11 through the gate tape-carrier-package 42 is positioned between the side surface of the mold frame 33 and the upper case 31.

In this case, the printed circuit board 41 may be formed of an upper case 31 or a lower case made of a metal material for the purpose of preventing deterioration of operating characteristics of the device due to electromagnetic interference (EMI) or noise. Grounded at 32).

Conventionally, a method of attaching the conductive tape 60 or a side screw 50 fastening method or the like is used as a grounding method of the printed circuit board 41.

That is, as shown in the drawing, the printed circuit board 41 is connected to the lower case 32 using the conductive tape 60 or the side surface of the printed circuit board 41 is connected using a screw 50 or the like. Connect to the upper case 31 so that it is grounded.

However, in the method of attaching the conductive tape, an assembly process is required because the tape is attached before the upper case is fastened, the liquid crystal display panel is inverted, the bottom case is connected with the ground, and the liquid crystal display panel is flipped again to fasten the upper case in place. There was a drawback to complexity and reduced workability.

In addition, when grounding using a screw, there is a problem such as the use of additional tools for fastening the screw and deterioration of workability due to the screw fastening at the side, as well as foreign matter inflow.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a liquid crystal display device which prevents electromagnetic interference and noise without degrading workability by grounding a printed circuit board using an improved grounding means.

In order to achieve the above object, the liquid crystal display device of the present invention comprises a liquid crystal display panel composed of an array substrate and a color filter substrate; A backlight unit disposed under the liquid crystal display panel; A driving circuit unit electrically connected to the array substrate and including a printed circuit board having at least one opening; A case including an upper case fixing the liquid crystal display panel, the driving circuit unit, and the backlight unit; And at least one grounding means divided into a first connecting portion electrically connected to the printed circuit board and a second connecting portion contacting the upper case, wherein the second connecting portion of the grounding means is opened through an opening of the printed circuit board. It protrudes and contacts the upper case.

The driving circuit unit including the printed circuit board includes a component formed on the first side of the printed circuit board and a tape-carrier package that electrically connects with the array substrate and electrically connects to the second side of the printed circuit board. It can be done by.

The first connection portion of the grounding means may be in electrical contact with the first surface of the printed circuit board.

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In addition, the grounding means may be made of an electrically conductive material having elasticity.

Hereinafter, exemplary embodiments of the liquid crystal display according to the present invention will be described with reference to the accompanying drawings.

3 is a partial cross-sectional view showing a liquid crystal display device according to a first embodiment of the present invention, and is shown centering on a printed circuit board including grounding means.

As shown in the drawing, a backlight unit 120 including a reflector 121, a light guide plate 122, and an optical sheet 123 is positioned on the lower case 132, and an array substrate is disposed on the backlight unit 120. 111 and the color filter substrate 112 are sequentially positioned. In this case, the mold frame 133 is positioned at the side of the backlight unit 120 to store and support the backlight unit 120.

In addition, the printed circuit board 141 connected to the array substrate 111 through the tape-carrier-package 142 is positioned between the side surface of the mold frame 133 and the upper case 131. The tape-carrier-package 142 may be a data tape-carrier-package or a gate tape-carrier-package.

At this time, the printed circuit board 141 is grounded through the upper case 131 made of a metal material and the grounding means 170 for the purpose of preventing the deterioration of operating characteristics of the device due to electromagnetic interference or noise.

The grounding means 170 is made of an electrically conductive material having an elastic force, and the portion which is grounded with the upper case 131 is bent to contact the side surface of the upper case 131 using elasticity.

At this time, the mounting surface of the component 143 of the printed circuit board 141 is in most cases an inner mold frame for increasing the size of the image display area, protecting the component 143 of the printed circuit board, and preventing a short. To 133. In this case, in order to attach the grounding means 170 to the opposite side of the mounting surface of the component 143, a double-sided mounting on the printed circuit board 141 is required.

However, double-sided mounting in printed circuit boards has a problem of making work progress difficult or increasing costs compared to single-sided mounting.

An embodiment employing a cross-sectional mounting grounding means for solving this problem will be described in detail below.

4 is a partial cross-sectional view showing a liquid crystal display device according to a second embodiment of the present invention.

This embodiment has the same structure as the liquid crystal display of the first embodiment shown in FIG. 3 except for the mounting method of the grounding means.

As shown in the drawing, a backlight unit 220 including a reflective plate 221, a light guide plate 222, and an optical sheet 223 is positioned on the lower case 232, and an array substrate is disposed on the backlight unit 220. 211 and the color filter substrate 212 are sequentially located. At this time, the mold frame 233 is located on the side of the backlight unit 220 serves to accommodate and support the backlight unit 220.

In addition, the printed circuit board 241 connected to the array substrate 211 through the tape-carrier-package 242 is positioned between the side surface of the mold frame 233 and the upper case 231.

At this time, the printed circuit board 241 is grounded through the upper case 231 and the grounding means 270.

The grounding means 270 is made of an electrically conductive material having elasticity, and a portion of the grounding means 270 which is grounded with the upper case 231 is bent to contact the side surface of the upper case 231 by using elasticity. In addition, the grounding means 270 is attached to the mounting surface of the component 243 of the printed circuit board 241 to improve the workability. That is, when the component 243 is mounted on the printed circuit board 241, the grounding means 270 is also mounted at the same time, thereby simplifying the manufacturing process and improving work efficiency.

The form and mounting method of the cross-sectional mounting grounding means 270 will be described in detail as follows.

5A and 5B are perspective views illustrating an enlarged view of the grounding means of the LCD shown in FIG. 4.

First, as shown in FIG. 5A, the grounding means 270 may include a first connection part 271 electrically connected to the printed circuit board 241 and a second connection part 272 electrically connected to the upper case 231. )                     

A portion where the first connecting portion 271 and the second connecting portion 272 contact each other is at a right angle, and the end of the second connecting portion 272 forms an elastic portion that protrudes from the body.

In the drawing, the contact portion with the upper case 231, which is the end of the second connection portion 271, is protruded and bent, but the contact portion may be folded or folded.

In this case, the mounting of the grounding means 270 is performed by the second connection portion 272 of the grounding means 270 through the first opening 243 formed in the printed circuit board 241. The upper case 231 may be brought into contact with the rear surface of the upper case 231. In the present exemplary embodiment, the grounding means 270 and the first opening 243 are configured to be one each, but the grounding means 270 and the first opening 243 are constituted of a plurality of upper cases 231. And effectively grounded.

In addition, the first connection portion 271 of the grounding means 270 may be electrically connected to the printed circuit board 241 in the same manner as the mounting of the component 243 of the printed circuit board 241.

In this embodiment, the grounding means 270 is mounted on the same surface at the same time as the component 243 mounting, and the upper case 231 is contacted to the ground through the first opening to be grounded. This can lead to improved gender and lower costs.

Next, as shown in FIG. 5B, another type of grounding means 270 may include a first connection part 271 electrically connected to the printed circuit board 241 and a first connection part electrically connected to the upper case 231. It consists of two connection parts 272a.

The contact portion between the first connection portion 271 and the second connection portion 272a forms a right angle, and the ends of the second connection portion 272a protrude from the body to form a plurality of bent elastic portions.

When the ends of the second connection portion 272a are configured in a plurality of branch shapes (or finger or bar shapes), the printed circuit board 241 and the upper case 231 are coupled to each other. It is possible to increase the elastic force, and one branch, which is made of metal, may be bent in an undesired direction by a certain impact, so that the other branch may contact even if the contact is broken, thereby increasing the safety of the ground.

On the other hand, the grounding means 270 to be fixed to the printed circuit board 241, there can be a variety of coupling methods, but to form a second opening 273 in the grounding means 270 to be fixed through a screw or the like Can be.

Many details are set forth in the foregoing description but should be construed as illustrative of preferred embodiments rather than to limit the scope of the invention. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the claims and the equivalents of the claims.

As described above, the liquid crystal display device of the present invention brings about the improvement of workability and cost reduction by grounding the printed circuit board using the single-sided mounting grounding means.

Claims (12)

A liquid crystal display panel composed of an array substrate and a color filter substrate; A backlight unit disposed under the liquid crystal display panel; A driving circuit unit electrically connected to the array substrate and including a printed circuit board having at least one opening; A case including an upper case fixing the liquid crystal display panel, the driving circuit unit, and the backlight unit; And At least one grounding means divided into a first connecting portion electrically connected to the printed circuit board and a second connecting portion contacting the upper case, wherein the second connecting portion of the grounding means protrudes through the opening of the printed circuit board. The liquid crystal display device, characterized in that the contact with the upper case. The liquid crystal display of claim 1, wherein the case further comprises a lower case and a mold frame. 2. The driving circuit unit of claim 1, wherein the driving circuit unit includes a component formed on a first side of the printed circuit board and a tape-carrier package that electrically connects with the array substrate and electrically connects to a second side of the printed circuit board. Liquid crystal display characterized in that made. 4. The liquid crystal display of claim 3, wherein the tape-carrier package is formed in a semi-bent form. The liquid crystal display device according to claim 1, wherein the first connection portion of the grounding means is electrically connected to the first surface of the printed circuit board. The liquid crystal display device according to claim 1, wherein the first connection portion of the grounding means further comprises an opening. 7. The liquid crystal display device according to claim 6, further comprising connecting means for electrically connecting the first connecting portion and the printed circuit board through the opening of the first connecting portion of the grounding means. The liquid crystal display of claim 1, wherein an end of the second connection portion of the grounding means protrudes from the body to form at least one branch. The liquid crystal display device according to claim 1, wherein the contact portion of the first and second connection portions of the grounding means forms a right angle. delete delete The liquid crystal display of claim 1, wherein the grounding means is made of an electrically conductive material having elasticity.

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