JP2598432Y2 - Matrix type liquid crystal display - Google Patents

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, and more particularly to a matrix type liquid crystal display.

[0002]

2. Description of the Related Art In recent years, regulations concerning electromagnetic wave noise standards and safety standards have become strict in matrix type liquid crystal display devices. As a countermeasure against the above-mentioned regulations, electrical conduction between the metal frame of the liquid crystal display device and the ground wiring of the printed wiring board is established, the potential of the metal frame is fixed at the ground level, and the impedance of the ground wiring of the printed wiring board is reduced. Has been implemented.

FIG. 3 is a sectional view showing a conventional means for electrically connecting a metal frame to a ground wiring of a printed wiring board. In this figure, 1 is a color filter substrate, 2
Is an array substrate overlaid with the color filter substrate,
Reference numeral 3 denotes a plastic frame supporting the array substrate 2, reference numeral 4 denotes a printed wiring board supported by the plastic frame 3 for driving a liquid crystal panel, and reference numeral 6 denotes a metal frame which presses and locates each constituent member against the plastic frame 3. , 7 TAB-IC, 8 is interposed between the TAB-IC 7 and the metal frame 6 silicone
Down rubber, 9 screws that secure the metal frame 6 in the plastic frame 3, 10 respectively show Subesagomu interposed between the metal frame 6 and the TAB-IC 7.

In the conventional matrix type liquid crystal display device having the above structure, the metal frame 6 and the printed wiring board 4
Is electrically connected to the ground wiring as follows. That is, as shown in FIG.
4 is fixed to the printed wiring board 4 by affixing it to the metal frame 6 with screws 9 or FIG.
As shown in FIG. 7, instead of the joint tightening with the screws 9, the metal frame 6 and the printed wiring board 4 are soldered to establish electrical continuity.

[0005]

The above-mentioned conventional structure has the following problems. That is, as shown in FIG. 3, in the conduction by the joint tightening with the screw 9, the electrical resistance is likely to increase due to insufficient tightening of the screw 9. If there is such insufficient tightening, the electric potential of the metal frame 6 becomes unstable and electromagnetic radiation noise increases. Further, in the conduction formation by soldering shown in FIG. 4, soldering failure on the metal frame 6 side is apt to occur, and not only an increase in electrical connection resistance is observed, but also the workability of soldering itself is poor, which is not preferable in manufacturing. .

The present invention has been made based on the above circumstances, and provides a matrix-type liquid crystal display device capable of ensuring electrical conduction between a metal frame and ground wiring of a printed wiring board.

[0007]

A matrix type liquid crystal display device according to the present invention comprises a matrix type liquid crystal panel, a printed wiring board required for driving the liquid crystal panel, and a metal for protecting the liquid crystal panel and the printed wiring board. In a liquid crystal display device comprising a frame and electrically connecting between the metal frame and ground wiring of the printed wiring board, a hole penetrating a ground wiring portion of the printed wiring board and a hole provided in the metal frame are respectively provided. The electrical continuity is formed by a coupling plug made of a conductive elastic body having projections to be fitted on both end surfaces. As the conductive elastic body, conductive rubber is suitable. Further, for example, the coupling plug is arranged such that a large number of fine wires whose surfaces are plated with gold in an insulating silicone rubber are aligned, and both ends thereof are exposed to both end surfaces of the insulating silicone rubber. It is formed using a conductive rubber that is buried.

[0008]

In the matrix type liquid crystal display device of the present invention having the above-mentioned structure, the electrical connection between the printed wiring board ground wiring and the metal cover is formed by the projection printed wiring board provided on both end surfaces of the coupling plug made of conductive rubber. Also, since it is obtained by fitting into a metal cover, there is no increase in electrical resistance due to insufficient tightening of the screws, and there are no problems caused by this.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 in which the same parts as those in FIGS.
FIG. 3 is a cross-sectional view showing a main part of one embodiment of the present invention. In this figure, a printed wiring board 4 is arranged on a plastic substrate 3 as in a conventional liquid crystal display device. Then, a hole 4a that penetrates a part of the ground wiring of the printed wiring board 4 to fit the coupling plug 5 made of conductive rubber.
And a hole 6a for the same purpose is provided at a position of the metal frame 6 facing the hole 4a. Coupling tap 5
Is the same as the spacer rubber 10 in the conventional liquid crystal display device shown in FIGS.
A large cross section 5a having a function of maintaining a gap between the B-IC 7 and the hole 4 protruding from one end face thereof;
a, and a projection 5c projecting from the other end face and fitting into the hole 6a. The protrusions 5b and 5c have the function of determining the relative position between the metal frame 6 and the printed wiring board 4, respectively.

FIG. 2A is a perspective view showing the details of the coupling plug. In this figure, the large cross section 5 of the coupling line 5 is shown.
a, each of the protrusions 5b and 5c is made of conductive rubber, and the outer periphery of the large diaper 5a is covered with an insulating silicone rubber.
Is provided.

The coupling plug 5 has the projection 5b fitted into the hole 4a of the printed wiring board 4, and the projection 6c is engaged with the hole 6a to cover the metal cover 6 on the printed wiring board 4. A caulking portion (not shown) is provided around the hole 6a of the metal cover 6, and by caulking the caulking portion, the coupling wire 5 and the metal frame 6 form an electrical contact, and the metal cover 6 6 and the ground wiring of the printed wiring board 4 are electrically connected.

In the liquid crystal display device of the present invention having the above-mentioned structure, the formation of the electrical continuity between the printed wiring board ground wiring and the metal cover is not obtained by co-tightening with a coupling screw, but is made of conductive rubber. Since the protrusions provided on both end surfaces of the coupling plug are obtained by fitting into the printed wiring board and the metal cover, an increase in electric resistance due to insufficient tightening of the screw, an indefinite potential of the metal frame due to this,
There is no increase in electromagnetic radiation noise.

FIG. 2B is a perspective view of a modification of the main part. In this modified example, the conductive rubber portion of the coupling plug 5 is formed by arranging a large number of fine metal wires 5e whose surfaces have been subjected to gold plating in an insulating silicone rubber material 5d in the same direction. The parts are respectively exposed and embedded at both end surfaces of the coupling plug 5. The same operation and effect as in the embodiment shown in FIG. 1 can be obtained by the coupling plug 5 having this configuration.

[0014]

As is apparent from the above description, in the liquid crystal display device of the present invention, the electrical connection between the metal frame and the ground wiring of the printed wiring board is made of conductive rubber without being screwed together. Since the plug projection is obtained by fitting the plug projection into both, the electrical conduction can be easily formed. In addition, the protrusion not only determines the relative position between the metal frame and the printed wiring board, but also prevents the displacement of the coupling plug itself. Also,
Since the coupling stopper according to the present invention also serves as a spacer rubber in a conventional liquid crystal display device, the number of components can be reduced and the structure of the device can be simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 2A is an enlarged perspective view of a main part of the embodiment, and FIG.
9 is an enlarged perspective view of a modification of the main part.

FIG. 3 is a cross-sectional view showing a conventional means for electrically connecting a metal frame to a ground wiring of a printed wiring board.

FIG. 4 is a sectional view showing a modified example of the electric conduction means.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02F 1/1345 G02F 1/1333 G09F 9/00 G09F 9/30

Claims (3)

(57) [Scope of request for utility model registration] A matrix type liquid crystal panel, a printed wiring board necessary for driving the liquid crystal panel, a metal frame for protecting the liquid crystal panel and the printed wiring board, and a ground for the metal frame and the printed wiring board. In a liquid crystal display device in which wiring is electrically connected, a conductive elastic body having projections at both end surfaces, each of which is fitted into a hole passing through a ground wiring portion of the printed wiring board and a hole provided in the metal frame. A matrix type liquid crystal display device, wherein the electrical conduction is formed by a coupling plug made of: 2. The matrix type liquid crystal display device according to claim 1, wherein the conductive elastic body is a conductive rubber. 3. A connecting plug is provided such that a large number of fine wires having a surface plated with gold in an insulating silicone rubber are aligned, and both ends thereof are exposed to both end surfaces of the insulating silicone rubber. 2. The matrix type liquid crystal display device according to claim 1, wherein the matrix type liquid crystal display device is formed using a buried conductive rubber.