JP3782480B2 - Display device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a display device used for a display of a personal computer, a viewfinder of a video camera recorder, and other various image information processing devices, and more particularly to a display device in which a circuit board and a display cell are supported by a cell support. Specifically, the present invention relates to a structure for supporting a circuit board on a cell support.
[0002]
[Prior art]
Conventionally, as a display device, an electroluminescence display (ELD), a plasma display (PD), a liquid crystal display (LCD) and the like are used in various fields.
[0003]
In this type of display device, a display cell formed by holding a liquid crystal between a pair of transparent substrates on which a large number of electrodes are formed has an adhesive on a cell fixing plate serving as a support for supporting the display cell. In addition, a driver board (circuit board) having a cell driving IC is arranged around the cell on the same cell fixing plate. The driver board includes a plurality of TAB-ICs each having a flexible tape connected to a terminal, and is electrically and mechanically connected to the display cell via a flexible TAB film of the TAB-IC. The driver board is supported by the cell fixing plate separately from the display cell so that the driver board does not jump greatly from the cell fixing plate when the display device receives vibration or impact.
[0004]
By the way, the cell fixing plate of the display device is made of glass reinforced polycarbonate, and the liquid crystal cell as the display cell is bonded by enclosing a liquid crystal material such as nematic liquid crystal or ferroelectric liquid crystal between a pair of glass plates. It consists of Therefore, these cell fixing plates and liquid crystal cells have different coefficients of thermal expansion. For this reason, when the environmental temperature changes or when a temperature stress is applied in the manufacturing process, the relative positions of the two change. At this time, if the driver board is fixed so as not to move with respect to the cell fixing plate, stress may be applied to the TAB film or a joint portion such as soldering at both ends thereof, and the driver board may be broken.
[0005]
Therefore, the driver board is supported so as to be able to move in a direction parallel to the cell fixing plate following the change in the relative position between the cell fixing plate and the liquid crystal cell.
[0006]
FIG. 6 is a main part perspective view showing a support structure of a driver board in a conventional display device, and FIG. 7 is a main part sectional view showing the same support structure.
[0007]
As shown in these drawings, conventionally, a long hole 21 or a U-shaped notch 22 is formed in the driver board 20, and a step screw 23 passed through the long hole 21 or the notch 22 is screwed to the cell fixing plate 25. By wearing, the driver board 20 was supported by the cell fixing plate 25 so as to be movable.
[0008]
[Problems to be solved by the invention]
However, in the support structure of the driver board 20 in the conventional display device as described above, the driver board 20 needs to have a space for forming the long hole 21 or the notch 22 in the driver board 20. It had become. In particular, when the driver board 20 is arranged on two adjacent sides of the display cell, the corner space SA shown in FIG. 6 is already occupied by the driver board 20 arranged on one side. There is no space for the fixed part (shown). Therefore, in order to fix the other driver board by the same method, there has been a problem that further space must be facilitated, resulting in an increase in the size of the apparatus.
[0009]
An object of the present invention is to provide a display device capable of assembling a circuit board in a compact manner while maintaining a good connection state between the circuit board and the display cell.
[0010]
[Means for Solving the Problems]
The present invention has been made in view of the above-described circumstances, and includes a display cell having a large number of electrodes, a cell support for supporting the display cell, and driving the display cell connected to the display cell. And a circuit board provided with a driving circuit, and the circuit board is movably supported by support means with respect to the cell support.
The supporting means is a holding plate that restricts the movement of the circuit board away from the cell support and supports the circuit board so as to move in a direction parallel to the cell support . In this case, the pressing plate may be a leaf spring for pressing the circuit board and the cell support.
[0011]
[Action]
Based on the above configuration, by using a pressing plate as the support means, the circuit board can be supported using a very small space on the upper surface of the circuit board. That is, the supporting space that must be secured on the circuit board can be made very small, and the circuit board can be downsized.
[0012]
In addition, by using a holding plate composed of a leaf spring, the circuit board can be moved in a direction parallel to the cell support, and there is no play in the direction perpendicular to the cell support, that is, there is no backlash. It becomes possible to support in the state which is not. At the same time, it is possible to cope with circuit boards having different thicknesses with the same size and shape of the holding plate.
[0013]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0014]
FIG. 1 is a plan view showing an entire liquid crystal display device according to the present invention, FIG. 2 is an exploded perspective view showing a main part of a driver board support structure in the liquid crystal display device, and FIG. FIG. 4 is a cross-sectional view taken along the line AA, and FIG. 4 is a cross-sectional view taken along the line BB of FIG. 1 showing the same support structure.
[0015]
As shown in FIG. 1, a liquid crystal cell (display cell) 2 for display is fixed to the center of a single cell fixing plate (cell support) 1 using an adhesive 3 and the liquid crystal cell. In the periphery of 2, a driver board (circuit board) 5 for driving cells is arranged. The driver board 5 has a plurality of TAB-ICs 6 mounted on the legs 1a of the cell fixing plate 1 and is electrically and mechanically connected to the liquid crystal cell 2 through a flexible TAB film 7. Has been. The TAB-IC 6 on the driver board 5 receives a drive signal from a control device (not shown) via a flat cable and drives the liquid crystal cell 2.
[0016]
The driver board 5 moves in a direction parallel to the cell fixing plate 1 following the change in the relative position between the cell fixing plate 1 and the liquid crystal cell 2 due to the environmental temperature change, as described in the conventional example. Supported to get. The liquid crystal display device according to the present invention is characterized by a support structure for the driver board 5 to the cell fixing plate 1.
[0017]
That is, the driver board 5 is supported by the presser plate 9 that restricts the movement of the board 5 in the direction perpendicular to the cell fixing plate 1 so as not to jump greatly when subjected to vibration or impact. 1, the driver board 5L located on the left side of the liquid crystal cell 2 can move in the X direction (left and right direction), and the driver boards 5F and 5R located in the front and rear directions can move in the Y direction (front and back direction).
[0018]
In the case of this embodiment, each driver board 5 is supported at its both ends and the center by a presser plate 9. Of the presser plate 9, the presser plate 9 </ b> A that supports both end portions of each driver board 5 is bent in a step shape (FIG. 3), and the tip portion is a portion without the TAB film 7 on the upper surface of the driver board 5. Further, it is fixed to the cell fixing plate 1 using screws 10 so as to overlap with a slight gap (0.1 to 0.2 mm). Further, of the holding plates 9A that support both ends of each driver board 5, those that support both ends of the driver board 5L located on the left side of the liquid crystal cell 2, and driver boards 5F that are located before and after the liquid crystal cell 2, What supports the left end of 5R is integrated in L shape, and is fixed to the cell fixing plate 1 with one screw 10.
[0019]
In addition, the holding plate 9B that supports the central portion of each driver board 5 is bent at both ends at a right angle to form a U-shape (FIG. 4), the hole 11 formed in the bent portion, and the cell fixing The cell fixing plate 1 is fixed by engaging with protrusions 12 formed on the legs 1 a of the plate 1. Even in the case of the holding plate 9B, the bent portion and the driver board 5 are further formed in a state where a slight gap (0.1 to 0.2 mm) is left in the portion of the upper surface of the driver board 5 where the TAB film 7 is not provided. The board 5 is fixed in a state where a gap is provided so as not to prevent movement of the board 5 in a direction parallel to the cell fixing plate 1.
[0020]
As described above, by using the presser plate 9, the driver board 5 can be supported using a very small space on the upper surface of the board. That is, the support space that must be secured in the driver board 5 can be made very small, and the driver board 5 can be downsized. Further, if the two adjacent pressing plates 9A are integrated, the assembling work can be simplified.
[0021]
<Other Examples>
In the previous embodiment, the presser plate 9 was provided with a slight gap between it and the upper surface of the driver board 5. However, as shown in the cross-sectional view of the main part of FIG. Alternatively, a plate spring made of a synthetic resin may be used, and the tip of the holding plate 90 made of the plate spring may be brought into pressure contact with the upper surface of the driver board 5. However, the pressure contact force of the presser plate 90 does not hinder the movement of the driver board 5 in the direction parallel to the cell fixing plate 1.
[0022]
In this way, by using the holding plate 90 formed of a leaf spring, the driver board 5 can be moved in a direction parallel to the cell fixing plate 1 and there is no play in a direction perpendicular to the cell fixing plate 1. In other words, it can be supported in a state without any backlash. At the same time, it is possible to apply the pressing plate 90 having the same size and shape to the driver board 5 having different thicknesses.
[0023]
Further, the holding plate may be made of a conductive member, and may be used as a ground terminal by holding it at a predetermined potential. It is easy to secure the ground potential by electrically connecting the holding plate to the ground terminal of the circuit board.
[0024]
In each of the above embodiments, the display cell is a liquid crystal cell. However, of course, the present invention is not limited to this, and a display cell in which an optical modulation material such as an electroluminescent material or an electrochromic material is sandwiched between a pair of substrates may be used. A display cell having an electron-emitting device array, a display cell having an array of reflecting mirrors, or the like may be used. The display cells and the circuit board are preferably connected with a conductive adhesive or the like via a flexible wiring member such as a tape carrier.
[0025]
【The invention's effect】
As described above, in the display device according to the present invention, the circuit board for driving the cell is structured to be supported by the cell support using the presser plate, so that the support space that must be secured on the circuit board is provided. The circuit board can be miniaturized. As a result, the entire display device can be reduced in size.
[0026]
In addition, by configuring the holding plate with a leaf spring and press-contacting the upper surface of the circuit board, the circuit board can be supported without any play, and at the same time, with the same dimensions and shape. The presser plate can accommodate circuit boards having different thicknesses.
[Brief description of the drawings]
FIG. 1 is a plan view showing an entire liquid crystal display device according to the present invention.
FIG. 2 is an exploded perspective view of a main part showing a driver board support structure in the same liquid crystal display device.
3 is a cross-sectional view taken along line AA of FIG. 1 showing the same support structure.
4 is a cross-sectional view taken along the line BB of FIG. 1 showing the same support structure.
FIG. 5 is an exploded perspective view of a main part showing another support structure of the driver board in the liquid crystal display device according to the present invention.
FIG. 6 is a perspective view of a main part showing a driver board support structure in a conventional liquid crystal display device.
FIG. 7 is a cross-sectional view of a main part showing the same support structure.
[Explanation of symbols]
1 Cell fixing plate (cell support)
2 Liquid crystal cell (display cell)
5 Circuit boards 9, 90 Presser plate (supporting means)

Claims (4)

A display cell having a large number of electrodes, a cell support for supporting the display cell, and a circuit board provided with a drive circuit connected to the display cell for driving the display cell, In a display device in which a circuit board is movably supported by a support means with respect to the cell support,
The support means is a presser plate that supports the circuit board so that the circuit board can move away from the cell support and can move in a direction parallel to the cell support .
A display device characterized by that. The pressing plate is a leaf spring for pressing the circuit board and the cell support.
The display device according to claim 1. The support means allows the circuit board to move relative to the cell support when the cell support is thermally expanded.
The display device according to claim 1, wherein the display device is a display device. The circuit board has a substantially rectangular shape, and the support means allows movement along the longitudinal direction of the circuit board.
The display device according to claim 1, wherein the display device is a display device.

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