KR101158869B1 - Structure for joining a Printed Circuit Board of liquid crystal display - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board fastening structure for a liquid crystal display device for fastening a predetermined circuit board to a cover, the nut being provided on a bottom surface of the cover and having a seating portion in which a bottom surface of the circuit board is surface-contacted. And a screw for fastening the circuit board cooperatively with the nut, the shaft part being fastened by the nut and the head part formed at an end of the shaft part, and the circuit board being generated while the height of the seat is relatively low. And a gap compensator provided between the circuit board and the head of the screw to compensate for a gap between the heads of the screws. As a result, it is possible to implement the slimming of the liquid crystal display device while preventing the occurrence of noise due to the assembly tolerance and preventing the fastening force of the screw to the circuit board from being weakened.

Liquid crystal display, circuit board, screw, nut, bite, fastening, gap compensation

Description

Structure for joining a printed circuit board of liquid crystal display

1 is a rear view of a general liquid crystal display device;

FIG. 2 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) according to the related art in the liquid crystal display of FIG. 1;

3 is an exemplary view for explaining a new problem of the circuit board fastening structure according to the prior art,

4 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) in a liquid crystal display according to a first exemplary embodiment of the present invention;

5 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) in a liquid crystal display according to a second exemplary embodiment of the present invention;

6 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) in a liquid crystal display according to a third exemplary embodiment of the present invention;

DESCRIPTION OF THE REFERENCE NUMERALS

10: cover 15: circuit board

20: nut 20a: thread

22: seating portion 24: step

30: screw 31: shaft portion

33: head part 35: inclined part

40a ~ 40c: gap compensation part

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board fastening structure for a liquid crystal display device, and more particularly, to reduce noise caused by assembly tolerances, and to prevent the fastening force of a screw on a circuit board from being weakened. The present invention relates to a circuit board fastening structure for a liquid crystal display device.

A liquid crystal display device uses a switching element to change a molecular arrangement of a liquid crystal material, and thereby to display a desired image by controlling an amount of light transmitted through a transparent insulating substrate, among which a thin film transistor is used. Thin-film transistor liquid crystal display devices (TFT LCDs) using a TFT) element as a switching element are mainly used.

Since the liquid crystal display is not a light emitting device that emits light by itself, a separate external light source is required, and a transmissive type that transmits light incident from the backlight unit by installing a backlight unit on the rear side according to the light source used, and a color filter substrate. It is divided into a reflection type that reflects external light such as external natural light or external auxiliary light incident on the array substrate via the color filter substrate toward the display surface.

In recent years, by combining the reflection type and the transmission type together in one pixel to combine the reflection type and the transmission type, it is possible to reduce unnecessary power consumption by using the backlight unit and to use the device even when the external light is dark. Research into a transflective liquid crystal display device having a wide range is being activated.

1 is a rear view of a general liquid crystal display device.

As shown in FIG. 1, a general liquid crystal display device has a cover 110 coupled to each other in a front-rear direction with a panel (not shown) having an image formed therebetween. In addition to various electric wires 111 or connection terminals 112, a so-called PCB (Printed Circuit Board) is also used as a means for transmitting an electrical signal to the panel in one area of the rear surface of the cover 110 (FIG. 2). Is mounted).

2 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) according to the related art in the liquid crystal display of FIG. 1.

As shown in this figure, a circuit board 115 (PCB) is disposed in one region of the cover 110 as a means for forming an electrical signal system. The circuit board 115 is fixed to one region of the cover 110 by the screw 130.

At this time, a nut 120 (PEM Nut) is provided on the bottom of the cover 110 adjacent to the circuit board 115 to secure the bite to the screw 130. The nut 120 includes a seating portion 122 on which the lower surface of the circuit board 115 is seated while being in surface contact, and a stepped portion 124 having a higher height than the seating portion 122.

Screw 130 is composed of a shaft portion 131 is inserted into the screw thread 120a formed on the inner surface of the nut 120 and fastened, and the head portion 133 is provided at the end of the shaft portion 131. The head 133 is formed in parallel with the circuit board 115 in a plate shape like a coin.

Referring to the method of fastening the circuit board 115 to the cover 110 by such a configuration as follows.

First, the circuit board 115 is placed on the seating portion 122 of the nut 120 while the through hole 115a of the circuit board 115 is fitted into the stepped portion 124 of the nut 120. Then, the shaft portion 131 of the screw 130 is inserted into the thread 120a formed on the inner surface of the nut 120 and fastened while rotating clockwise. Then, since the lower surface of the circuit board 115 is in close contact with the seating portion 122 and the upper surface of the circuit board 115 is in close contact with the lower surface of the head 133 of the screw 130, the circuit board 115 is firm at the corresponding position. Can be fixed.

On the other hand, in recent years, efforts have been made to gradually reduce the thickness of the liquid crystal display (Slim). In order to reduce the thickness of the liquid crystal display, a method of reducing the mounting portion 122 from the reference height L1 of FIG. 2 to the height L2 of FIG. 3 has been taken.

However, when the mounting portion 122 is lowered from the height L1 of FIG. 2 to the height L2 of FIG. 3, the height at which the circuit board 115 is disposed is lowered, thereby making it possible to realize slimming of the liquid crystal display device. Although there is, a gap is inevitably generated between the head 133 of the screw 130 and the circuit board 115. Therefore, since the adhesion between the screw 130 and the circuit board 115 is inevitably reduced, not only the circuit board 115 can be firmly fixed but also the noise due to the assembly tolerance due to the gap is generated. There is a problem that occurs.

In order to solve this problem, the mounting part 122 was lowered to the height L2 of FIG. 3 while the height H of the stepped part 124 was also considered. However, when the height L2 of the seating portion 122 and the height H of the stepped portion 124 are lowered together, the nut 120 is inevitably reduced in thickness. Therefore, another problem occurs that the fastening force of the screw 130 to the circuit board 115 is weakened because the bite amount of the screw 130 to the nut 120 can be reduced by that much.

Therefore, the technical problem to be achieved by the present invention is to prevent the occurrence of noise due to the assembly tolerances, while preventing the weakening of the fastening force of the screw to the circuit board for the liquid crystal display device to realize a slim (Slim) It is to provide a circuit board fastening structure.

Technical problems to be achieved by the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

According to an aspect of the present invention, a circuit board fastening structure for a liquid crystal display device for fastening a predetermined circuit board to a cover is provided on a bottom surface of the cover, and the bottom surface of the circuit board is in surface contact with one region. And a nut having a seating portion to be seated thereon, a shaft portion fastened to the nut, and a head portion formed at an end of the shaft portion, and the height of the screw and the seating portion cooperatively fixing the circuit board with the nut is relatively low. And a gap compensating part provided between the circuit board and the head of the screw to compensate for a gap between the circuit board and the head of the screw.

Here, one end of the gap compensation part may be fixed to the head and the other end may be in contact with and supported on an upper surface of the circuit board.

The gap compensation portion is bent toward the circuit board from the outer circumferential surface of the head portion.

The lower surface of the gap compensation part is formed parallel to the circuit board, and preferably forms a relatively wide contact surface.

The gap compensation part may be integrally formed with the head of the screw.

On the other hand, one end of the gap compensation portion may be fixed to the circuit board and the other end may be supported in contact with the lower surface of the head.

In this case, the gap compensation portion is advantageously formed integrally with the circuit board.

The gap compensation part may be formed separately from the head of the screw and the circuit board, and may be fitted into a gap between the circuit board and the head of the screw.

The gap compensation portion may be ring-shaped or partially engraved.

Specific details of other embodiments are included in the detailed description and the drawings. Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. Like reference numerals refer to like elements throughout.

Hereinafter, a circuit board fastening structure for a liquid crystal display according to the present invention will be described in detail with reference to FIGS. 3 to 6.

First embodiment

4 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) in the liquid crystal display according to the first exemplary embodiment of the present invention.

As shown in this figure, a circuit board 15 (PCB) is disposed in one region of the cover 10 as a means for forming an electrical signal system. The circuit board 15 is fixed at the corresponding position by the screw 30. The screw 30 is responsible for the ground (Ground) function for the circuit board 15 in addition to the role of fixing the circuit board 15 to the cover 10.

In order to secure the amount of bite to the screw 30, a nut 20 (PEM Nut) is provided on the bottom of the cover 10. The nut 20 has a height at which the bottom of the circuit board 15 is seated while being in surface contact with the seat 22, and the height of the nut 20 is higher than that of the seat 22. The jaw portion 24 is made up. The seating portion 22 forms a relatively wide contact surface to more stably support the lower surface of the circuit board 15. The upper surface of the inner surface of the stepped part 24 is formed to be inclined so as to be shaped to the inclined portion 35 of the screw 30 to be described later.

The screw 30 includes a shaft portion 31 inserted into and fastened to a screw thread 20a formed on the inner surface of the nut 20, a head portion 33 provided at an end of the shaft portion 31, a shaft portion 31 and a head. The inclined portion 35 is formed between the portions 33.

Meanwhile, as described above, in the first embodiment of the present invention, the mounting portion 22 is lowered from the reference height L1 of FIG. 2 to the height L2 of FIG. 4 to slim the liquid crystal display. It was. By lowering the seating part 22 to the height L2 of FIG. 4, the circuit board 15 can be disposed to the lower side of the bottom of the cover 10, thereby making the overall liquid crystal display slim. have.

However, when the mounting portion 22 is lowered from the reference height L1 of FIG. 2 to the height L2 of FIG. 4, a gap Gap is formed between the circuit board 15 and the head 33 of the screw 30. However, this gap Gap is provided with a gap compensation part 40a, thereby solving the problem of occurrence of intermittent noise due to the gap Gap and a weakening force of the screw 30 at the same time.

The gap compensation portion 40a according to the first embodiment is formed integrally with the head portion 33 of the screw 30. Typically, the screw 30 is formed of copper or sus (SUS) material, so that the gap compensation portion 40a may be integrally formed when the screw 30 is manufactured.

Therefore, one end of the gap compensation part 40a is integrally fixed to the head 33 and the other end is supported by contact with the upper surface of the circuit board 15. That is, it has a shape bent toward the circuit board 15 from the outer peripheral surface of the head 33. At this time, the lower surface of the gap compensation portion 40a is formed parallel to the circuit board 15, it is advantageous to form a relatively wide contact surface. Only then will the upper surface of the circuit board 15 be more stably contacted. Of course, the length of the gap compensation part 40a is formed by the length of the gap Gap generated when the seating part 22 is lowered from the reference height L1 of FIG. 2 to the height L2 of FIG. 4.

Referring to the method of fastening the circuit board 15 to the cover 10 by such a configuration as follows.

First, the circuit board 15 is disposed on the seating portion 22 of the nut 20 while the through hole 15a of the circuit board 15 is fitted into the stepped portion 24 of the nut 20. The lower surface of 15) is to be in surface contact support to the seating portion (22).

Then, the shaft portion 31 of the screw 30 is inserted into the thread 20a formed on the inner surface of the nut 20 and fastened while rotating clockwise. Then, the lower surface of the circuit board 15 is in close contact with the seating part 22, and the upper surface of the circuit board 15 is lower surface of the gap compensation part 40a formed integrally with the head 33 of the screw 30. While being in close contact with it will be able to be firmly fixed in the position.

Therefore, as in the prior art, it is possible to prevent the occurrence of noise due to the assembly tolerance and to realize the slimming (Slim) of the liquid crystal display device while preventing the fastening force of the screw 30 to the circuit board 15 from being weakened.

Second Embodiment

FIG. 5 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) in a liquid crystal display according to a second exemplary embodiment of the present invention.

In the second embodiment of the present invention, unlike the first embodiment described above, the gap compensation portion 40b is integrally formed on the circuit board 15. That is, one end of the gap compensation portion 40b is integrally fixed to the circuit board 15 and the other end is in contact with the lower surface of the head 33 of the screw 30. At this time, the length of the gap compensation part 40b is formed by the length of the gap Gap generated when the seating part 22 is lowered from the reference height L1 of FIG. 2 to the height L2 of FIG. 5.

With this configuration, the circuit board 15 is disposed on the seating portion 22 of the nut 20 while the through hole 15a of the circuit board 15 is fitted into the stepped portion 24 of the nut 20. The lower surface of the circuit board 15 is to be in surface contact with the mounting portion 22.

Then, the shaft portion 31 of the screw 30 is inserted into the thread 20a formed on the inner surface of the nut 20 and fastened while rotating clockwise. Then, the lower surface of the circuit board 15 is in close contact with the seating portion 22, and the lower surface of the head 33 of the screw 30 is on the upper surface of the gap compensation portion 40b formed integrally with the circuit board 15. It will be able to be firmly fixed in the position while being in close contact.

Therefore, the second embodiment can also prevent the noise caused by the assembly tolerance as in the prior art, while preventing the weakening of the fastening force of the screw 30 to the circuit board 15 to implement slimming (Slim) of the liquid crystal display device. It will be possible.

Third Embodiment

FIG. 6 is a cross-sectional view illustrating a circuit board fastening structure (region A of FIG. 1) in a liquid crystal display according to a third exemplary embodiment of the present invention.

Referring to this figure, in the third embodiment of the present invention, unlike the first and second embodiments described above, the gap compensation portion 40c is not integrally formed on the screw 30 or the circuit board 15. It is manufactured separately without. That is, the gap compensation part 40c is provided in the ring shape like a washer, or a partial piece shape.

With this configuration, first, the circuit board 15 is attached to the seating portion 22 of the nut 20 while the through hole 15a of the circuit board 15 is fitted into the stepped portion 24 of the nut 20. The bottom surface of the circuit board 15 is placed in surface contact with the seating part 22.

Next, the gap compensation portion 40c is disposed on the upper surface of the circuit board 15 in a ring shape or a partial piece shape. Then, the shaft portion 31 of the screw 30 is inserted into the thread 20a formed on the inner surface of the nut 20 and fastened while rotating clockwise.

Then, the lower surface of the circuit board 15 is in close contact with the seating portion 22, and the lower surface of the head 33 of the screw 30 is in close contact with the upper surface of the gap compensation portion 40c disposed on the circuit board 15. While pressurizing the gap compensation part 40c, the bottom surface of the gap compensation part 40c is brought into close contact with the top surface of the circuit board 15, so that the circuit board 15 can be firmly fixed at the corresponding position.

Accordingly, the third embodiment may also prevent noise generation due to assembly tolerances as in the prior art, and prevent the fastening force of the screw 30 on the circuit board 15 from being weakened, but also realize a slimming of the liquid crystal display device. It will be possible.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. Therefore, since the embodiments described above are provided to fully inform the scope of the invention to those skilled in the art, it should be understood that they are exemplary in all respects and not limited. The invention is only defined by the scope of the claims.

According to the circuit board fastening structure for a liquid crystal display device according to an embodiment of the present invention made as described above, it is possible to prevent the generation of noise due to the assembly tolerance. In addition, while preventing the fastening force of the screw on the circuit board from being weakened, there is an effect of realizing slimming of the liquid crystal display.

Claims (10)

In a circuit board fastening structure for a liquid crystal display device which fastens a predetermined circuit board to a cover, A nut provided on a bottom surface of the cover and having a seating portion in which a bottom surface of the circuit board is seated in surface contact with a bottom portion of the seating portion, and a stepped portion which is formed at a height higher than that of the seating portion; A screw for fastening the circuit board cooperatively with the nut having a shaft portion fastened by the nut and a head portion formed at an end of the shaft portion; And It includes a gap compensation portion provided between the circuit board and the head of the screw to compensate for the gap (Gap) between the circuit board and the head of the screw that occurs when the height of the seat is relatively low, And one end of the gap compensation part is fixed to the head part and the other end is integrally formed with the head part of the screw so as to be in contact with the upper surface of the circuit board. delete The method of claim 1, And the gap compensation part is bent toward the circuit board from the outer circumferential surface of the head and integrally formed with the head of the screw. The method according to claim 1 or 3, And a lower surface of the gap compensator is formed in parallel with the circuit board to form a relatively wide contact surface. delete In a circuit board fastening structure for a liquid crystal display device which fastens a predetermined circuit board to a cover, A nut provided on a bottom surface of the cover and having a seating portion in which a bottom surface of the circuit board is seated in surface contact with a bottom portion of the seating portion, and a stepped portion which is formed at a height higher than that of the seating portion; A screw for fastening the circuit board cooperatively with the nut having a shaft portion fastened by the nut and a head portion formed at an end of the shaft portion; And It includes a gap compensation portion provided between the circuit board and the head of the screw to compensate for the gap between the circuit board and the head of the screw that occurs when the height of the seat is relatively low, And one end of the gap compensator is fixed to the circuit board and the other end is integrally formed on the circuit board so as to be in contact with the lower surface of the head. delete delete delete 7. The method according to claim 1 or 6, The through-hole of the circuit board is inserted into the stepped portion of the nut, the bottom surface of the circuit board is a circuit board fastening structure for the liquid crystal display device, characterized in that the surface contact support.

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