JP2000019513A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily carry out the mounting and dismounting of a CFL to and from a unit case without using a tool, such as a screw driver. SOLUTION: The side wall 26 of the unit case 21 of the liquid crystal display device having a side light type backlight unit constituted by arranging the cold cathode tube (CFL) 40 of a straight tube type into a light source housing part existing alongside a light transmission plate in the unit case 21 is provided with an aperture 231 which allows the putting in and out of the CFL 40 along its axis direction in communication with the light source housing part.

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 having a sidelight type backlight unit on the back side of a liquid crystal display panel, and more particularly, to a technology capable of easily replacing the backlight. Things.

[0002]

2. Description of the Related Art A backlight unit is disposed on the rear side of a transmissive or transflective liquid crystal display panel. The backlight unit is roughly classified into a direct type and a sidelight type. FIG. 6 shows a configuration of a CFL storage unit of a sidelight type backlight unit having a straight tube type cold cathode tube (CFL) as a conventional example. It is shown.

FIG. 6 is an exploded perspective view of the CFL storage section 2 of the backlight case 1 as viewed from the rear side thereof. Although not shown, a light guide plate is arranged in the backlight case 1. The liquid crystal display panel is disposed below the backlight case 1 in FIG.

[0004] The CFL storage section 2 includes a backlight case 1
Is formed as a concave portion 2a along one side surface (light receiving surface) of a light guide plate (not shown).
A CFL3 as a light source is stored in a.

[0005] The CFL 3 is a straight tube type, and tube end holders 3a, 3b made of soft synthetic resin are attached to both ends thereof, and lead wires 4a, 4b for power supply are drawn out from the tube end holders 3a, 3b. And each of them is a connector 5
It is connected to the.

The CFL storage section 2 is provided with a strip-shaped cover plate 6 formed so as to fit into the upper opening of the recess 2a. In this conventional example, a cover plate 6 serves as a mounting means for the backlight case 1, and a tongue piece 6 a having a through hole for screwing is formed at a central portion thereof, and locking claws 6 b formed on both sides of the cover plate 6. , 6b.

On the other hand, on the backlight case 1 side, a female screw hole 7a is provided at a position corresponding to the tongue piece 6a having a through hole, and a female screw hole 7a is provided at a position corresponding to each locking claw 6b. Stop holes 7b, 7b are provided respectively.

After the CFL 3 is stored in the concave portion 2a of the CFL storage portion 2, the cover plate 6 has its locking claws 6b,
6b is put on the CFL housing portion 2 so as to be locked in the locking holes 7b, 7b of the backlight case 1, and a tongue piece 6a with a through hole at the center thereof is screwed into the female screw hole 7a. It is screwed by the screw 7.

[0009]

FIG. 7 shows the cover plate 6 attached to the CFL housing 2 in this manner.
However, according to this conventional example, there are the following problems.

First, since the cover plate 6 and the screws 7 for fixing the cover plate 6 to the backlight case 1 are required, the number of parts increases accordingly. Next, since a mold for molding the cover plate 6 is required, the cost cannot be denied.

Further, even if the cover plate 6 is attached and detached, the work procedure involves a screwing operation of the screw 7 and the workability is not good. Further, since this kind of cover plate 6 contributes to downsizing of the entire apparatus, CF
It is formed so as to fit into the concave portion 2 a of the L housing 2.

For this reason, when removing the cover plate 6, as shown in FIG. 6, after removing the screws 7, the cover plate 6 must be further pryed open with, for example, a flathead screwdriver 8. This is especially C
This makes the replacement of the FL3 more difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to eliminate the need for a CFL cover plate and to use a CFL for a unit case without using a tool such as a screwdriver. It is an object of the present invention to provide a liquid crystal display device which can be easily attached and detached.

[0014]

In order to achieve the above object, the present invention comprises a liquid crystal display panel and a backlight unit disposed on the back side of the liquid crystal display panel, wherein the backlight unit is a liquid crystal display. A unit case having a light irradiating window on the surface facing the display panel, and a straight tube type disposed in a light guide plate provided in the unit irradiating window and a light source storage portion on the side of the light guide plate. In a liquid crystal display device of a sidelight type having a cold cathode fluorescent lamp (CFL), an opening is formed in a side wall of the unit case so as to communicate with the light source housing and to allow the CFL to be taken in and out along the axial direction. It is characterized by being.

As described above, since the CFL can be inserted into and taken out of the light source housing from the side of the unit case, not only the cover plate becomes unnecessary, but also
The exchange can be easily performed.

In this case, a side plate for routing a lead wire drawn from the CFL and having a coating made of a soft polymer material is continuously provided on the side wall of the unit case, and the lead plate is locked to the side plate. It is preferable that a claw is provided to hold the CFL in the light source housing via the lead wire. According to this, the CFL can be easily fixed without using a screw that requires a tool or the like.

Further, by forming the locking claw into a shape cut and raised from the side plate, it becomes possible to integrally form the locking claw together with the side plate with the unit case with a resin.

A tube end holder made of a soft polymer material is provided at one end of the CFL, and a folded lead extending to the tube end holder along the CFL is connected to the tube end electrode at the other end. , The CFL has a slim shape, and the space for the CFL storage portion in the unit case can be saved.

Further, the CFL can be easily fixed by providing a flange plate provided with an opening on the upper edge side of the opening to be fitted with the projection provided on the tube end holder.

[0020]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to an embodiment shown in the drawings. FIG. 1 is a cross-sectional view of the liquid crystal display device according to this embodiment viewed from the direction of the line AA in FIG. 2, FIG. 2 is a plan view of a backlight unit used in the liquid crystal display device, and FIG. FIG.

As shown in FIG. 1, this liquid crystal display device has a transmissive or transflective liquid crystal display panel 10.
And a backlight unit 20 disposed on the back side of the liquid crystal display panel 10 via a spacer 15 made of rubber or the like. These are housed in an outer case 30.

The liquid crystal display panel 10 has a pair of transparent electrode substrates 11 and 12 bonded together via a peripheral sealing material (not shown), and a predetermined liquid crystal substance is sealed in the cell. Each transparent electrode substrate 11, 12 has a polarizing film 13, 1
3 are stuck. Further, on one transparent electrode substrate 12, a terminal portion 121 on which an extraction electrode group is formed is continuously provided.

The backlight unit 20 has a unit case 21 made of synthetic resin. The unit case 21 has an upper surface facing the liquid crystal display panel 10 opened as a light irradiation window, and a light guide plate 22 is housed therein. On the light receiving surface 221 side of the light guide plate 22, a light source housing 23 is provided along the light receiving surface 221, and a straight tube type CFL (cold cathode tube) 40 is housed in the light source housing 23. .

The bottom of the unit case 21 has a CFL4
An appropriate inclination is provided for directing light from 0 to the liquid crystal panel 10 side, and a light reflection sheet 24 is additionally provided from the bottom surface and the side surface of the light source housing portion 23 to the upper surface thereof. A light diffusion sheet 25 is provided on the upper surface of the light guide plate 22.
Is provided.

The terminal portion 121 of the liquid crystal display panel 10 includes
One end of a TCP (tape carrier package) substrate 50 on which an LSI chip 51 as a liquid crystal driving electronic component is mounted is connected. The other end of the TCP board 50 is connected to a circuit board 53 on the bottom side of the unit case 21 via a bus board 52 such as a flexible printed board.

Referring now to FIG. 4, which is a perspective view of a main part on the bottom side of the backlight unit 20, one side wall 26 of the unit case 21 has an opening communicating with the light source housing 23. Portion 231 is formed, and C
The FL 40 can be put into and taken out of the light source housing 23 through the opening 231. Also, the unit case 21
A side plate 27 is continuously provided so as to protrude from the side wall 26 side.

A tube end holder 41 made of a soft polymer material is attached to one end of the CFL 40 for the purpose of protecting and insulating a soldered portion.

The tube electrode on the other end of the CFL 40 is
A folded lead 42 is connected to the tube end holder 41 along the FL 40.

From the pipe end holder 41, two lead wires 44 for supplying power to the CFL 40 are drawn out. The lead wire 44 has a coating made of a soft polymer material, and although not shown in detail, one of the leads is made of CFL4.
0 is connected to the tube end electrode on one end side, and the other lead is an extension lead of the folded lead 42 from the tube end electrode on the other end side. The end of the lead wire 44 is provided with a connector 5 similar to the conventional one.

In the present invention, as the soft polymer material used as the covering material of the tube end holder 41 and the lead wire 44, silicone rubber or fluorine rubber is preferably exemplified from the viewpoint of elasticity and heat resistance.

The lead wire 44 is routed over the side plate 27 to a predetermined power supply unit. The side plate 27 is provided with a locking claw 28 for locking a part of the lead wire 44. . In this embodiment, the locking claw 28 is integrally formed with the side plate 27 and is cut and raised from the side plate 27 in an inverted L-shape with a tip protruding downward.

That is, an opening 2 formed by inserting a molding die (not shown) is inserted below the locking claw 28.
81, in this case, the locking claw 28 and the opening 2
The distance from the upper surface of 81 is slightly smaller than the thickness of the lead wire 44.

Therefore, by forcibly fitting the lead wire 44 from the end portion of the locking claw 28 so as to pass under the locking claw 28, a part of the lead wire 44 sinks into the opening 281 and is securely fixed by the locking claw 28. Will be retained.

At this time, the locking claw 2 is
By laying the lead wires 44 so that the lead wires 44 do not slack up to 8, the CFL 40 can be fixed in the light source housing 23 of the unit case 21 via the lead wires 44.

According to this configuration, when assembling the product, the CFL 40 is inserted into the light source accommodating portion 23 through the opening 231 and a part of the lead wire 44 is locked by the locking claw 28, thereby fixing the CFL 40. can do.

On the other hand, when replacing the CFL 40, the CFL 40 can be easily pulled out from the light source housing 23 by removing the lead wire 44 from the locking claw 28 and setting it free. There is no need to use tools such as a screwdriver for any work.

It should be noted that, as shown in FIG.
31 is an eave-like flange plate 2 having an opening 291 on the upper edge side
9 is provided, and the projection 4 provided on the tube end holder 41 is provided in this portion.
11 may be fitted to fix the CFL.

[0038]

As described above, according to the present invention,
In a liquid crystal display device having a sidelight-type backlight unit in which a straight-tube-type cold-cathode tube (CFL) is arranged in a light source storage portion located on a side of a light guide plate in a unit case, a light source is provided on a side wall of the unit case. Communicating with the storage section C
By providing an opening through which the FL can be taken in and out along the axial direction, the CFL can be easily attached to and detached from the unit case without using a tool such as a screwdriver, and a cover plate for the CFL is provided. Is also unnecessary.

The CFL is provided on the side wall of the unit case.
A side plate for routing the lead wire drawn out from the side plate is provided in series, and a locking claw for locking the lead wire is provided on the side plate, or a projection provided on the tube end holder on the upper edge side of the opening is fitted. By providing a flange plate provided with an opening to allow the CFL to be
Can be fixed in the light source housing.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 2 showing one embodiment of a liquid crystal display device according to the present invention.

FIG. 2 is a plan view of a backlight unit used in the embodiment.

FIG. 3 is a left side view of FIG. 2;

FIG. 4 is an essential part perspective view of the backlight unit as viewed from the bottom surface side.

FIG. 5 is a perspective view of a main part of a backlight unit according to another embodiment as viewed from the bottom surface side.

FIG. 6 is an exploded perspective view of a backlight unit used in a conventional liquid crystal display device as viewed from the back side thereof.

FIG. 7 is a rear perspective view of the conventional backlight unit with a cover plate attached thereto.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Liquid crystal display panel 20 Backlight unit 21 Unit case 22 Light guide plate 23 Light source storage part 231 opening 26 Side wall 27 Side plate 28 Locking claw 30 Outer case 40 CFL (cold-cathode tube) 41 Tube end holder 42 Folding lead 44 Lead wire

Claims (5)

[Claims] 1. A unit case including a liquid crystal display panel and a backlight unit disposed on the back side of the liquid crystal display panel, wherein the backlight unit has a light irradiation window on a surface facing the liquid crystal display panel. A liquid crystal display device of a sidelight type having a light guide plate provided in the unit case facing the light irradiation window and a straight-tube cold-cathode tube disposed in a light source storage portion beside the light guide plate. A liquid crystal display device, wherein an opening is formed in a side wall of the unit case so as to communicate with the light source accommodating portion and to allow the cold cathode tube to be inserted and removed along an axial direction thereof. 2. The unit case has a side plate connected to the side wall so as to extend a lead wire drawn out of the cold cathode tube and having a coating made of a soft polymer material and extending to the side wall. 2. The liquid crystal display device according to claim 1, further comprising a locking claw for holding the cold cathode tube in the light source housing via the lead wire. 3. The liquid crystal display device according to claim 2, wherein the locking claw is cut and raised from the side plate. 4. A tube end holder made of a soft polymer material is provided at one end of the cold cathode tube, and a tube end electrode at the other end of the cold cathode tube is provided along the cold cathode tube. 4. The liquid crystal display device according to claim 1, wherein a folded lead is connected to the tube end holder. 5. The liquid crystal according to claim 4, wherein an eave-shaped flange plate provided with an opening for fitting with a projection provided on the tube end holder is provided on an upper edge side of the opening. Display device.