JPH047519A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To securely fix and hold a liquid crystal cell by providing a through hole for exposing the liquid crystal cell which has its periphery drawn and pressing the connection part between the liquid crystal cell and a driving element. CONSTITUTION:The through hole 41 for exposing the liquid crystal cell 1 whose periphery is drawn is formed in the center of a frame body 4 which is formed of a metallic plate to store the liquid crystal cell and driving element 2. In this frame body 4, elastic rubber 5 is installed which abuts on the corner end edge (for example, cut part S at the intersection projection part between upper and lower substrates) of the liquid crystal cell 1, and this is made of a cylindrical elastic body and fixed convering the boss 32 of a holder 3. Thus, the frame body 4 is drawn at the peripheral edge of the thorough hole 41 to produce no burr at the end edge of the metallic plate, the frame body hardly deforms because of a formed step, and the connection part between the liquid crystal cell 1 and driving element 2 is pressed by the frame body 4 to prevent the connection part from being peeled. Consequently, the liquid crystal cell 1 is securely fixed and held.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a liquid crystal display device, so-called a liquid crystal module, which integrally includes a liquid crystal cell, a driving element, and an illumination means.

(B) Prior Art Conventionally, liquid crystal display devices have been provided in a form that integrates a liquid crystal cell, its driving element, and illumination means, and is easy to use in devices such as word processors and personal computers. Such a liquid crystal display device is disclosed in, for example, Japanese Unexamined Patent Publication No. 2-3
As disclosed in Japanese Patent Application No. 3125, etc., a drive element is arranged around a liquid crystal cell, and the liquid crystal cell and lighting means are stacked and housed in a metal frame or the like.

(c) Problems to be Solved by the Invention However, such liquid crystal display devices have several problems.

First, a through hole is provided in the metal frame to expose the effective display surface of the liquid crystal cell, but since a punching method is used to form the through hole, a hole is created, and if the hole is placed inside, the liquid crystal The surface of the cell may be scratched or the liquid crystal cell may crack, and if the liquid crystal display is placed on the outside, it may damage the decorative panel of the device when the liquid crystal display device is installed in the device. Although such scratches and scratches are small, since the entire surface of the display device attracts attention, even a slight scratch is extremely noticeable and is inconvenient.

Next, the display area of liquid crystal cells has become larger year by year, and recently there are many 85-sized to A4-sized ones, and the wiring is connected over a long length, so the positioning of the liquid crystal cell requires a large panel. This must be done with an accuracy of approximately ±0°5mm.

On the other hand, the display center may shift due to the molding accuracy of the positioning means (generally a resin molded product), the liquid crystal cell may not be stored in the specified position, or the positioning means and the liquid crystal cell may overlap with each other when a metal frame is fitted. This often results in damage to the liquid crystal cell, and the distance from the effective display surface of the liquid crystal cell to the edge of the display device is long due to the arrangement of the driving elements, making it insufficiently secured with the metal frame, and the liquid crystal cell may be damaged after assembly. Movement and poor conduction occurred at the connection parts, and in particular, the wiring material often peeled off at the connection part between the drive element and the liquid crystal cell.

Furthermore, by stacking the liquid crystal cell and the illumination means, not only does the liquid crystal display device become thicker, but also the contrast change due to the temperature dependence of the liquid crystal cell tends to occur mainly in the part near the light source due to the heat generated by the illumination means. Display quality is significantly degraded.

(d) Means for Solving the Problems The present invention has been made in view of these points, and includes a liquid crystal cell, a drive element connected to the periphery of the liquid crystal cell, and a drawing process applied to the periphery. It has a through hole that exposes the liquid crystal cell, and has an elastic rubber inside that contacts the corner edge of the liquid crystal cell, so that at least the liquid crystal cell and the driving element are pressed so as to press the connection part between the liquid crystal cell and the driving element. It is provided with a frame made of a metal plate for storage, and an illumination means laminated on the back of the liquid crystal cell and having a light source on the side and a reflector that covers the bottom and the light source, more preferably a part with elastic rubber. This fixes the frame and the lighting means.

(E) If the peripheral edge of the working hole is drawn, not only will the edge of the metal plate not be burred, but the formed step will make it difficult to deform, and the metal plate will be held securely. In addition, the elastic rubber provides a margin for positioning the liquid crystal cell and prevents damage to the cell.

In the lighting means, the light source is covered with a reflective plate, so the heat is diffused by the anti-elbow plate.

Furthermore, by fixing it with an elastic rubber part, it is possible to obtain a pressing force along the edge of the liquid crystal cell, and since it is located in the relatively central part of the frame, the heat dissipation space can be reduced by using a lighting means with a relatively small area. You can create shapes and create a thin appearance.

(F) Embodiment FIG. 1 is an exploded perspective view of a liquid crystal display device of the present invention, and FIGS. 2 and 3 are sectional views of essential parts of the device.

In the figure, reference numeral 1 denotes a liquid crystal cell, for example, a field-effect type called super-twist nematic in which a twistedly aligned liquid crystal is sandwiched between two glass substrates. are stacked and have polarizing plates on the top and bottom, and terminals made of transparent electrodes (not shown) are provided around the periphery.

Reference numeral 2 denotes a drive element connected to terminals on the periphery of the liquid crystal cell 1 either directly or by a connection means such as heat sealing.
ding: Nikkei Microdevice Magazine February 1990 issue 1
A drive element using a drive element (see page 03) is directly fixed, held on the back side by a printed circuit board 21, and connected to this.

If necessary, driving elements 22 such as bias circuits and control elements are wired with flat cables 23 and placed nearby, but in order to make the display device thinner, these driving elements 22 are It is preferable to arrange it on the back side of the holding frame 3.

3 is a holding frame on which the liquid crystal cell 1 and drive element 2 are placed;
It is made of a resin molded product, etc., and has a through hole 31 in the center, and is provided with a boss 32 that is a protrusion with a through hole located slightly outside the corner edge of the liquid crystal cell 1.

Reference numeral 4 denotes a frame body made of a metal plate that houses the liquid crystal cell 1 and the drive element 2, and has a through hole 41 in the center that exposes the liquid crystal cell 1, which has been drawn around the periphery. Moreover, this frame 4 has an elastic rubber 5 disposed therein, which comes into contact with the corner edge of the liquid crystal cell 1 (for example, the notch-shaped portion S in the intersecting protrusion of the upper and lower substrates). Holding frame 3 consisting of the body
It is fixed by placing it over the boss 32 of. When the holding frame 3 is not used, it may be wound around a fixing screw or the like separately implanted in the frame body 4.

In the example shown in the figure, the frame 4 has fixing holes 43 at locations corresponding to the bosses 32 where the elastic rubber 5 is located, mounting sections 44 at the four corners for fixing the display device itself to the equipment, and the side surfaces. By bending the provided claws 45 on the back surface of the holding frame 3, a so-called display portion is integrated. Through hole 43
may be large enough to be penetrated by an integrated screw, which will be described later, but is preferably larger than the boss 32, so that the liquid crystal cell 1 will not accidentally rest on the boss 32 or the elastic rubber 5 during assembly. However, since the situation can be visually determined through the through hole 43 of the frame 4, the liquid crystal cell 1 will not be damaged.

Furthermore, since the through hole 41 exposes the effective display surface, the step 46 facing the inner surface formed by the drawing process is located near the periphery of the liquid crystal cell 1, but this step 46 directly , or press the connecting portion A between the liquid crystal cell 1 and the drive element 2 against the holding frame 3 via the cushioning material 51 at or near the stepped portion 46 .

Reference numeral 6 denotes illumination means laminated on the back side of the liquid crystal cell 1, which includes a light guide plate 61 made of transparent acrylic resin or the like with a light diffusion sheet 62 laid on the surface, and a cold cathode tube arranged on the side surface of the light guide plate 61. The light source driving means (
For example, when an inverter circuit) 66 is required, the reflector 64
It is preferable to place it outside of the area for heat dissipation and noise prevention.

This reflective plate 64 is made of a molded metal plate or the like, and has through holes 6 for fixing it in locations corresponding to the bosses 32 where the elastic rubber 5 is located.
5 is provided. By passing the integrated bisfoil together with the frame body 4 and the holding frame 3 through the through hole 65, the display portion and the illumination means described above are integrated. The location corresponding to the elastic rubber 5 means that it is located at the edge of the corner of the liquid crystal cell l, so if it is placed at the four corners of the liquid crystal cell, the liquid crystal cell l and the drive element will be located on the straight line connecting these four points. 2 to the illumination means 6 with the frame 4 more reliably.

(G) Effects of the Invention In the present invention, as described above, if the frame is drawn at the periphery of the through hole, not only will the edge of the metal plate not have any cracks, but it will also be less likely to deform due to the formed step. Since this frame presses the connecting portion between the liquid crystal cell and the drive element, not only the fixing of the liquid crystal cell is ensured, but also separation of the connecting portion can be prevented. Furthermore, since the liquid crystal cell is positioned using elastic rubber, there is sufficient margin for positioning the liquid crystal cell, and the liquid crystal cell is not damaged. In the lighting means, a reflector covers the light source, so the heat is diffused by the reflector.
Heat distribution becomes uniform. Therefore, the contrast of only a specific portion does not change, and display quality can be maintained at a high level.

Furthermore, when the parts are fixed using elastic rubber, a pressing force is obtained along the edges of the liquid crystal cell, so that the component parts can be fixed more reliably. Furthermore, in this case, since the integral fixation is at a relatively central portion of the frame, the illumination means can have a relatively small area. That is, since the illumination means only needs to have a light guide plate area larger than the effective display surface, it can be made smaller than at least the area where the driving elements are arranged. This creates a space around the back surface of the frame, which can be used as a heat radiation space B, allowing efficient heat radiation from the heat generating section. Furthermore, although the display section of devices that use such liquid crystal display devices is often independent, it is possible to provide a sloped section on the rear side of the display section of such devices so that the area on the back side is smaller than the front surface. To give the user an impression that the thickness of the display section is thin.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a liquid crystal display device of the present invention, and FIGS. 2 and 3 are sectional views of main parts of the fixed portion and the central portion of the long side of the device. ...Liquid crystal cell, ...Drive element, ...Holding frame, ...Frame body, 1...Through hole (of frame body), 5...Elastic rubber, 6 ...Lighting means.

Claims (1)

[Claims] (1) A liquid crystal cell, a drive element connected to the periphery of the liquid crystal cell, and an elastic rubber that has a through hole that exposes the liquid crystal cell that has been drawn around the periphery and that contacts the corner edge of the liquid crystal cell. a frame body made of a metal plate that houses the liquid crystal cell and the driving element so as to press the connecting part between the liquid crystal cell and the driving element; 1. A liquid crystal display device comprising: illumination means having a bottom surface and a reflector that covers a light source.