JP2000137208A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to screw a backlight unit, a circuit board, a chassis plate or the like at a time by using one screw by inserting a male screw, which is screwed down to a screw accepting part, to each hole for the screw of the unit case, the circuit board and the chassis plate and then screwing them to a case main body. SOLUTION: A circuit board 40 is mounted on a backlight unit 30. A chassis plate 50 is provided at the back side of the case main body 10 so as to cover the circuit board 40. The chassis plate 50 is screwed on to each supporting pole 14 in the four corners. Though the backlight unit 30 and the circuit board 40 are possible to slide against the case main body 10, each part is screwed on to the case main body 10 by one male screw 60 inserted from the chassis plate side 50, at the time of the assembly. Then, the male screw is screwed down to a screw accepting part through a hole 312 for the screw, thereby each part can be screwed to the case main body 10 at a time by using only one screw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device with a backlight, and more particularly, to a technique for fixing a backlight unit, a circuit board, and a chassis plate to a case body.

[0002]

2. Description of the Related Art In particular, when a CFL (cold-cathode tube) is used as a backlight of a liquid crystal display panel, maintenance is taken into consideration because CFLs are frequently exchanged as compared with other light sources (for example, light emitting diodes). Usually, the backlight unit is detachable from the case body by, for example, a slide mechanism.

On the back side of the backlight unit, a circuit board for driving a backlight or a liquid crystal display panel is arranged, and a chassis plate for radio wave shielding is also provided as a back cover so as to cover the circuit board. .

[0004]

As described above, in a liquid crystal display device with a backlight, the backlight unit is slidably attached to the case body.
In addition, a circuit board, a chassis plate, and the like are also attached. Conventionally, each of them is individually screwed to the case body. For this reason, many screwing operations are required and productivity is poor.

In addition, even if the circuit board is connected to the chassis plate and grounded, conventionally, for example, a metal leaf spring is soldered to the ground pattern of the circuit board, and the leaf spring is connected to the chassis plate. However, this work was also complicated, and improvement in this respect was also required.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to provide a backlight unit, a circuit board, a chassis plate and the like.
It is an object of the present invention to provide a liquid crystal display device that can be screwed at a time with a set of screws.

According to the present invention, the above object has a case body formed in a frame shape having an opening, a liquid crystal display panel is arranged on one surface side of the case body, and the other of the case body. A backlight unit and a circuit board for irradiating the liquid crystal display panel with light through the opening on the surface side of the liquid crystal display device, and the circuit board side is covered with a chassis plate; A screw receiving portion is provided in a predetermined portion of the unit case, and a screw insertion hole coaxially aligned with the screw receiving portion is formed in each of the unit case of the backlight unit, the circuit board, and the chassis plate, The unit case, the circuit board, and the chassis plate are lifted up with male screws screwed into the screw receiving portions through the respective screw insertion holes. It is achieved by screwing the case body.

According to the present invention, an earth pattern is formed around the screw insertion hole of the circuit board,
Between the circuit board and the chassis plate, a cylindrical conductive spacer is coaxially positioned with respect to each of the screw insertion holes, and is disposed with the male screw. The ground pattern of the circuit board can be electrically connected to the chassis plate via the conductive spacer.

In this case, the conductive spacer may be made of metal such as brass or conductive rubber. Further, it is not always necessary to be a complete cylindrical body, and for example, a part may be C-shaped in section cut in a slit shape along the axial direction.

When the case body is made of a synthetic resin, the screw receiving portion can be a cylindrical boss integrally formed with the case body. In this case, a tapping screw is used as a male screw. .

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a first embodiment of the present invention. FIG. 1 is a sectional view of the liquid crystal display device of this embodiment in an upside down state.
FIG. 2 is an exploded perspective view of the main part. FIG. 3 is a plan view of the case main body, and FIG. 4 is a sectional view taken along line AA of FIG.

This liquid crystal display device has a case main body 10 serving as a skeleton of the device. As shown in the plan view of FIG. 3, the case main body 10 is made of a synthetic resin frame 11 having an opening 10a, and a panel for accommodating the liquid crystal display panel 20 is provided on the lower surface side in FIG. A storage section 12 is formed. As shown in FIG. 4, a light diffusing plate (or sheet) 13 is arranged in the panel storage portion 12 so as to cover the opening 10a.

In FIG. 1, on the upper surface side of the case main body 10 (the rear surface side as viewed from the liquid crystal display panel 20 side), pillars 14 for screwing are provided at four corners thereof. In this embodiment, the case main body 10 is rectangular, and a pair of right and left columns provided at the lower corners of FIG.
a and 14b, and a pair of right and left columns provided at each corner on the opposite side is 14c and 14d.
Side walls 15a and 15d are provided between columns 4a and 14d, between columns 14b and 14c, and between columns 14c and 14d, respectively.
b, 15c are formed, and the support 14a
And 14b are open.

The space surrounded by the side walls 15a, 15b, and 15c is the component storage section 16, in which the backlight unit 30 and the circuit board 40 are stored. The backlight unit 30 has a unit case 31 having a built-in CFL (not shown) as a light source. The unit case 31 is slidable with respect to the component storage section 16 with a doorway between the columns 14a and 14b.

To this end, guide rails 151 and 151 are provided on the side walls 15a and 15b, whereas the guide rails 15 are provided on both sides of the unit case 31.
Guide grooves 311 and 311 are formed as mating members 1 and 151. In FIG. 1, the sliding direction of the backlight unit 30 is a direction orthogonal to the paper surface.

According to this embodiment, the circuit board 40 is mounted on the backlight unit 30. A chassis plate 50 is covered on the back side of the case body 10 so as to cover the circuit board 40. The chassis plate 50 is screwed to each of the columns 14 at the four corners.

The backlight unit 30 and the circuit board 40 are slidable with respect to the case body 10,
According to the present invention, at the time of assembly, each of these members is formed by one male screw 60 inserted from the chassis plate 50 side.
Screwed to case body 10.

Referring to FIG. 2, the case body 10 is provided with a screw receiving portion for the male screw 60. In this embodiment, the screw receiving portion is provided as a cylindrical boss 111 at a central portion on the entrance side of the component storage portion 16, that is, at an intermediate position between the columns 14a and 14b. The case body 10 is made of a synthetic resin, and the boss 111 is formed integrally with the case body 10. A tapping screw is used for the male screw 60.

In each of the backlight unit 30, the circuit board 40, and the chassis plate 50, screw insertion holes 312, 401, and 5, which are coaxially aligned with the boss 111, are provided.
01 are formed respectively.

An earth pattern 402 is formed around the screw insertion hole 401 of the circuit board 40. To establish conduction between the ground pattern 402 and the chassis plate 50,
Between the circuit board 40 and the chassis plate 50, a cylindrical spacer 61 having conductivity is provided with each of the screw insertion holes 40.
1,501 and coaxially. In this example, the spacer 61 is made of a brass sleeve, and is fixed to the screw insertion hole 501 of the chassis plate 50 by caulking.

According to this configuration, the backlight unit 30 and the circuit board 40 are housed at predetermined positions in the component housing portion 16 of the case main body 10, so that the boss 111, the screw insertion hole 501 of the chassis plate 50, and the spacer 61
With respect to the backlight unit 30 and the circuit board 4
0 is screwed into the boss 111 by inserting the male screw 60 from the chassis plate 50 side, and thereby the backlight unit 30 and the circuit board 40 can be fixed. The ground pattern 402 and the chassis plate 50 are electrically connected. By removing the male screw 60, the backlight unit 30 and the circuit board 40 can be pulled out of the case body 10.

In the above embodiment, the chassis plate 50 is screwed to each of the columns 14, but may be fixed to the case body 10 only with the male screw 60. In the above embodiment, the circuit board 40 is connected to the backlight unit 30.
Although mounted on the top, only the circuit board 40 may be slidable on the case body 10 as a single unit.

On the contrary, the backlight unit 3
The embodiment in which the circuit board 40 and the circuit board 40 are housed in the component housing 16 from the back side of the case body 10 is also included in the present invention. Further, by modifying the above-described embodiment, the liquid crystal display panel 20 may be arranged so as to face the opening 10a on the component housing 16 side of the case body 10.

[0024]

As described above, according to the present invention,
While providing a screw receiving part at a predetermined part of the case body,
Screw insertion holes that are coaxially aligned with the screw receiving portions are respectively formed in the backlight unit, the circuit board, and the chassis plate, and male screws are screwed into the screw receiving portions through the respective screw inserting holes. Thereby, each member can be screwed to the case body at a time with one screw.

Therefore, the assembling and disassembly are easy, and the number of screwed portions can be reduced. Therefore, it is possible to cope with a narrower frame, a smaller size, etc., which are recently required for the liquid crystal display device.

Further, according to the present invention, by arranging the tubular conductive spacer between the ground pattern of the circuit board and the chassis plate, conduction between the two can be achieved by screwing. it can. Therefore, the conventional leaf spring terminal plate dedicated to grounding and the work of soldering the same are not required, and the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a liquid crystal display device according to the present invention.

FIG. 2 is an exploded perspective view of a main part of the embodiment.

FIG. 3 is a plan view showing a case body in the embodiment.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Case main body 10a Opening 111 Boss 12 Panel storage part 14 Support 16 Parts storage part 20 Liquid crystal display panel 30 Backlight unit 31 Unit case 312, 401, 501 Screw insertion hole 40 Circuit board 402 Ground pattern 50 Chassis board 60 Male screw 61 Spacer

Claims (2)

[Claims] 1. A case body formed in a frame shape having an opening, a liquid crystal display panel is arranged on one surface side of the case body, and the opening is passed through the opening on the other surface side of the case body. A backlight unit for irradiating the liquid crystal display panel with light and a circuit board are arranged, and the circuit board side is covered with a chassis plate. In the liquid crystal display device, a screw receiving portion is provided at a predetermined portion of the case body. The unit case of the backlight unit, a screw insertion hole coaxially aligned with the screw receiving portion is formed in each of the unit case, the circuit board, and the chassis plate. The circuit board and the chassis plate are connected to each other by a male screw screwed into the screw receiving portion through each screw insertion hole. The liquid crystal display device characterized in that it is screwed to. 2. A ground pattern is formed around a screw insertion hole of the circuit board, and a coaxial position is provided between the circuit board and the chassis plate with respect to each of the screw insertion holes. A cylindrical conductive spacer to be aligned is arranged, and with the screwing by the male screw, the ground pattern of the circuit board is electrically connected to the chassis plate via the conductive spacer. The liquid crystal display device according to claim 1, wherein: