JP2003217329A - Assembling method, structure of back light unit and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for easily assembling a slidably detachable back light unit. <P>SOLUTION: A sheet reflector 15 having holes 15j, 15k, 15m, 15n to be inserted with protrusive nails 33-36 is laid on a jig 30 having the protrusive nails 33-36 in the four corners of its bottom surface 31, and a light guide plate 14 is placed on the reflector 15 so that it is fit in a frame confined by the protrusive nails 33-36 inserted in the holes 15j, 15k, 15m, 15n of the reflector 15. In addition, a light source 11 is disposed facing the three sides of the light guide plate 14 so as to take the form of a channel shape, a holder 16 is disposed on the remaining one side to guide the lead wire 12 of the light source 11 along its guide groove 16a, the bending margins 15a of three sides around the reflector 15 are glued to the upper surface of the light guiding plate 14 by bending them into channel shapes so as to wrap up the light source 11, and the bending margin 15b of the remaining one side is glued to the side of the holder 16 by bending it to a L shape. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and structure for assembling a backlight unit of a display device having a liquid crystal screen.

[0002]

[Prior art]

[0003]

A backlight provided behind a liquid crystal panel is used for illuminating a liquid crystal display in a dark place. This backlight is generally assembled as an integrated product (backlight unit) including a light guide plate and a sidelight type lamp.

Since the characteristics of the backlight greatly depend on the absolute arrangement or relative positional relationship of the components such as the light guide plate, it is necessary to perform accurate positioning during assembly. For example, by providing the light guide plate with a mechanism that engages with the reflector, the positional relationship between the two can be accurately matched. Especially when the reflector doubles as the housing of the backlight unit, the lamp can be positioned,
The variation in the performance of each product can be reduced.

However, as the weight of liquid crystal display devices has been reduced in recent years, the backlight unit is also required to be thinner and smaller, and as a result, the material used for the reflector needs to be soft and lighter. Become.

Therefore, the present inventor devised a backlight unit which can be slidably inserted into and removed from the main body of the apparatus in pursuit of workability of maintenance such as lamp replacement. In this slide type backlight unit, since the light guide plate is inserted and removed as a frame by sliding the reflector on a flat surface, a thin sheet-like reflector is adopted in consideration of its slipperiness and lightness.

However, if a light guide plate is provided with projections and the projections are inserted into the holes provided in the reflector and aligned to assemble the backlight unit, when the backlight is used, the light of the lamp is emitted from the light guide plate. It leaks to the outside through the protrusion. Therefore, the brightness of the backlight is sacrificed.

The present invention has been made in view of the above problems, and an object thereof is to provide a method for easily assembling a slide detachable backlight unit.

[0009]

In order to achieve the above object, a method of manufacturing a backlight unit according to the present invention is a sheet having a hole having a plurality of projecting claws on its bottom surface and having holes through which the projecting claws are inserted. -Shaped reflector is laid, the light guide plate is placed on the reflector so that the protruding claws inserted into the holes of the reflector are fitted into the frame, and the light source is arranged opposite to the side surface of the light guide plate. It is characterized in that folding folds around the reflector are bent so as to be wrapped and adhered to the upper surface of the light guide plate. According to this method, only by mounting the light guide plate with the protruding claws inserted through the reflector as a frame, accurate positioning can be performed quickly.

Specifically, the method for manufacturing a backlight unit according to the present invention comprises a jig having protruding claws at the four corners of the bottom surface.
A sheet-like reflector having a hole through which the projection claw is inserted is laid, and a light guide plate is placed on the reflector so that the projection claw inserted into the hole of the reflector is fitted into the frame, and further the light guide plate of the light guide plate is inserted. The light sources are arranged to face each other in a U-shape on three side surfaces, the holder is arranged on the remaining one side surface, and the lead wire of the light source is guided along the guide groove of the holder, so that the light source can be wrapped around the light source. It is characterized in that the folding white on the three sides is bent into a U-shape and adheres to the upper surface of the light guide plate, and the remaining folding white on the one side is bent into an L-shape and adheres to the side surface of the holder. . According to this method, only by mounting the light guide plate with the protruding claws inserted through the reflector as a frame, accurate positioning can be performed quickly.

Then, inclined sides are chamfered at the two corners of the light guide plate, step portions are formed at the remaining two corners, and a pair of the projecting claws and the inclined sides are brought into contact with each other to form a remaining pair. If the protruding claw and the step are brought into contact with each other, it becomes easy to fit the light guide plate and remove the backlight after assembling.

Further, by providing wall surfaces on the three sides of the bottom surface of the jig that face the light source, the folding folds of the reflector can be easily bent, and the bent shape can be adjusted. In addition, if perforations are provided at the folding positions of the folding screen, it becomes easier to fold.

The backlight unit of the present invention has a structure that is easy to assemble on a jig having protruding claws at the four corners.
That is, a reflector on a sheet having a hole into which the projection claw is inserted and having a folding fold that can be bent in a U shape on the three sides, and the projection claw inserted into the hole are used as a frame. A light guide plate that is mounted on the reflector without a rock, a light source that is arranged to face three side faces of the light guide plate, a holder that is arranged on the other one side face of the light guide plate, and a light source that is connected to the light source. Along with
The structure is provided with two lead wires that are taken out to the back side of the light guide plate through the guide grooves in the longitudinal direction of the holder, and a connector connected to these lead wires. As is clear from this structure, when the completed backlight unit is viewed from the rear side, the reflector has a hole in which the protruding claw of the jig is inserted.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 10 is a front perspective view of the liquid crystal module 1 used in the display device. The liquid crystal module 1 includes a liquid crystal panel 3 inside a frame 2 having a display window 2a on the front surface, and the display surface of the liquid crystal panel 3 is exposed from the display window 2a of the frame 2.
The liquid crystal panel 3 is contained in a resin case 4. A cover 5 is attached around the frame body 2 to protect the frame body 2.

FIG. 11 is a perspective view of the liquid crystal module 1 as viewed from the rear side, showing a state in which the cover 5 is removed. A flat plate-shaped rear metal fitting 6 is attached to the rear surface side of the frame body 2 so as to have a gap of a predetermined thickness between the rear metal fitting 6 and the liquid crystal panel 3. A backlight unit 10 described later is detachably mounted in the gap.

A board 7 on which various functional parts are mounted is screwed to the rear surface of the rear metal fitting 6. On the back surface of the substrate 7, the insertion port 2b of the backlight unit 10 (see FIG.
3) side is provided with a connector 8 and a connector 13 of the backlight unit 10 is detachably coupled to the connector 8. Further, a shield 9 is screwed to the rear surface of the rear metal fitting 6 to protect a part of the substrate 7.

FIG. 12 shows the entire liquid crystal module 1 (a).
FIG. 3 is a cross-sectional view of the main part (b). In resin case 4,
The diffusion plate 21 and the lens film 2 are provided on the back side of the liquid crystal panel 3.
2. The three light control sheets 20 including the diffusion plate 23 and the diffusion plate 23 are sequentially stacked. The number of light control sheets 20 may be two, or may be a combination other than this. The light emitted from the light emitting surface of the backlight unit 10 is adjusted by the light control sheet 2
A value of 0 provides a surface light source with more uniform brightness, which makes the display on the liquid crystal panel 3 easier to see.

Here, the reason why the light control sheet 20 is not integrally incorporated in the backlight unit 10 is that these are parts that do not need to be replaced semipermanently, and the light guide plate 14 is not inserted when the backlight unit 10 is inserted or removed. It is also for preventing the light control sheet 20 from being rubbed and damaged.

FIG. 13 shows a state where the backlight unit 10 is extracted from the frame body 2. The backlight unit 10 uses the flat-type light guide plate 14 as a framework to form the frame 2
The reflector 15 can be inserted and removed by sliding the reflector 15 on the slide surface of the front surface of the rear metal fitting 6 from the insertion port 2b. Backlight unit 10
At the time of inserting / removing, the gap between the liquid crystal panel 3 and the rear metal fitting 6 is sealed by the backlight unit 10 itself,
The frame 2 has a structure in which dust and dust are unlikely to enter.

The structure of the backlight unit 10 will be described in detail below. 1 is a perspective view of the backlight unit 10 when assembled, FIG. 2 is a front perspective view of the completed backlight unit, and FIG. 3 is a rear perspective view thereof.

The light guide plate 14 is formed by using a transparent and planar rectangular plate-like member such as acrylic, and two adjacent corners 14a and 14b are chamfered to form an inclined side 14.
c, 14d. These inclined sides 14c, 14
d is formed so as to abut against the claws 33 and 34 of the jig 30, respectively. In addition, stepped portions 14j and 14k parallel to the short side 14h are formed by notches in the other two adjacent corners 14x and 14y. These step portions 14j and 14k are formed so as to contact the claws 35 and 36 of the jig 30, respectively, and are recessed inward with a slight step from the short side 14h.

The lamp 11 is composed of a cold cathode tube having a U-shaped planar shape, which is arranged so as to face the three sides 14e, 14f, 14g of the light guide plate 14 including the two corners 14a, 14b. . The lamp 11 has a central straight line portion 11a and left and right straight line portions 11b and 11c at both ends thereof, so that the lamp 11 is bent into an L-shape corresponding to the corners 14a and 14b of the light guide plate 14. Both ends of the lamp 11 are covered with silicon caps 19, and the two lead wires 1
2 and 12 are pulled out.

As the light guide plate 14 and the lamp 11, those conventionally used as parts of a backlight can be used as they are. Therefore, the backlight unit 10 can procure main components as inexpensive off-the-shelf products, and suppress a sharp increase in product price.

A holder 16 is provided on the short side 14h of the light guide plate 14 on which the lamp 11 is not provided. The holder 16 is made of a resin molded product having a dark color tone such as black or gray, and also plays a role of blocking light leaking from the light guide plate 14. In the longitudinal direction of the holder 16, the lead wire 1
The two guide grooves 16a extend, and the two lead wires 12 are guided so as not to sag on the groove 16a.
It is taken out from the take-out groove 16b to the back side of the light guide plate 14, bundled and connected to the connector 13.

The holder 16 is integrally formed with a claw 18 having a thin projection shape and made of the resin material of the holder 16. Further, a cylindrical screw receiver 17 is provided at the center of the holder 16. A screw groove into which the screw 24 (see FIG. 13) is screwed is cut on the inner surface of the screw receiver 17. Corresponding to the screw receiver 17, as shown in FIG. 13, the rear metal fitting 6 is provided with a circular screw holding portion 6a for fixing the screw 24.

Around the reflector 15 made of a resin sheet, as shown in the plan view of FIG. 4, folding whites 15a which are bent in a U-shape are provided on three sides facing the lamp 11, and the rest is left. The folding white 15b that is bent into an L shape is provided on one side of the. These folded white 1
Perforations 15c are provided in 5a and 15b so as to be easily bent along the bending line. In addition, the folding white 15b may be bent in a U-shape depending on the shape of the holder 16, or may be adhered to the holder 16 while being flat without being bent. In terms of strength, it is best to fold it in a U-shape.

The reflector 15 has two adjacent corners 1.
5u, 15v, inclined side 15 formed by chamfering
s, 15t. These inclined sides 15s, 15
Since t can be confirmed at a glance of the backlight unit 10, it can also be used to confirm the front and back and the direction of the backlight unit 10. Further, small rectangular insertion holes 15j and 15k are formed in the corners 15u and 15v in an oblique direction. These insertion holes 15j, 15k
Is the sliding direction of the backlight unit 10 (see FIG.
The direction of the arrow) and the claws 33, 34 of the jig 30 in a direction perpendicular to
It is provided for inserting. In addition, in the other two adjacent corners 15x and 15y, a small rectangular insertion hole 15 is also provided.
m and 15n are perforated. These insertion holes 15m, 1
5n is a claw 35 of the jig 30 in a direction perpendicular to the sliding direction of the backlight unit 10 (the direction of the arrow in FIG. 13).
It is provided for inserting 36.

Further, the reflector 15 is a holder 1
6 has a width corresponding to the length between the take-out grooves 16b, 16b, and is cut out in a rectangular shape from the folding sill 15b to the inside so that the lead wire 12 can be taken out to the back side of the light guide plate 14 from the cut-out portion 15d. Has become. 15e and 15f are
These are holes through which the screw receiver 17 and the claw 18 of the holder are inserted.

The jig 30 used for assembling the backlight unit 10 is, for example, a thin plate product of coated steel plate processed into a rectangular shape, and has a short side 30e and a long side 30f adjacent to each other.
A wall surface 32 is formed integrally with the bottom surface 31 at 30g. Corner 30a where short side 30e and long side 30f intersect, short side 3
In the corner 30b where 0e and the long side 30g intersect, the claws 33, 34
Are provided on the bottom surface 31, respectively. Also, the wall surface 32
In the corner 30c where the short side 30h and the long side 30f intersect, and the corner 30d where the short side 30h and the long side 30g intersect, the claws 35, 3 are provided.
6 are provided on the bottom surface 31, respectively. These nails 3
3, 34, 35, and 36, for example, by punching the bottom surface 31 in a U-shape and raising it to the side with the wall surface 32,
It can be easily formed.

The pair of claws 33, 34 are not parallel to the short side 30e but are formed obliquely so as to have a predetermined angle. The angle is defined by the inclined sides 14c, 1 of the light guide plate 14.
It coincides with the direction of 4d. Remaining pair of claws 35, 36
Are provided parallel to the short side 30h. The area on the bottom surface 31 surrounded by these four claws 33, 34, 35 and 36 defines the position where the light guide plate 14 is placed, as shown in FIG. When the light guide plate 14 is arranged on the bottom surface 31 of the jig 30 in this manner, the claws 33 and 34 and the inclined sides 14c and 14d are respectively brought into contact with each other as shown in FIG. 7A, and also shown in FIG. 7B. So that nail 3
The stepped portions 14j and 14k come into contact with the portions 5 and 36.

The procedure for assembling the backlight unit 10 according to the present invention will be described below with reference to FIG. First, the reflector 15 is laid on the bottom surface 31 of the jig 30.
At this time, the claws 33, 34, 35 and 36 are inserted into the insertion holes 15j, 15k, 15m and 15n at the four corners of the reflector 15, respectively. As a result, as shown in the cross-sectional view of FIG.
Bends along the inner surface of the wall surface 32 at the inner sewing surface 15c. In this way, the wall surface 32 plays a role of facilitating the folding white 15a of the reflector 15 to be bent in a U-shape and adjusting the bent shape.

Then, the front and back of the light guide plate 14 are checked so that the claws 33, 34, 35 and 36 are fitted into the frame, and then the light guide plate 14 is mounted straight on the reflector 15. This allows
The light guide plate 14 is arranged on the jig 30 without any looseness, and is accurately positioned.

Next, the three sides 14e, 14f of the light guide plate 14,
The lamp 11 is arranged so as to face 14g. At this time, in consideration of the dimensional tolerance of the lamp 11, as shown in the cross-sectional view of FIG. 8, the lamp 11 should be arranged substantially in the center of the space between the side surface of the light guide plate 14 and the folding groove 15a of the reflector 15. To Further, the short side 14h of the light guide plate 14
Place the holder at 16 along. At this time, the screw receiver 17 and the claw 18 are attached to the holes 15e and 15f of the reflector 15.
The lead wire 12 is guided along the groove 16a and the take-out groove 16b, and the connector 13 is brought to the back side of the light guide plate 14.

The folding white 15a is bent at the outer perforations 15c so as to wrap the lamp 11, and the folding white 15a is placed along the side surface of the holder 16.
B is bent into an L shape. Finally, as shown in the cross-sectional view of FIG. 9, double-sided tape 25 is formed on the inner surfaces of the folding creases 15a and 15b on the upper surface of the light guide plate 14 and the side surface of the holder 16, respectively.
Adhere with. As a result, the light guide plate 14, the lamp 11 and the holder 16 can be integrated with each other only by the reflector 15. The fragile lamp 11 is the reflector 1
Since it is protected by 5, the backlight unit 10 can be easily handled. When the backlight unit 10 is slowly lifted, the jig 30 that is no longer needed can be claws 33, 3
4, 35 and 36 come off and come off easily.

When the completed backlight unit 10 is viewed from the rear side, as shown in FIG. 3, the projections 15j, in which the claws 33, 34, 35 and 36 of the jig 30 are inserted, are provided at the four corners of the reflector 15, as shown in FIG. 15k, 15m and 15
n remains. However, since these are very small holes, there is no fear that the light of the lamp 11 leaks, and the reflection efficiency of the reflector 15 is hardly disturbed.

In the above embodiment, the jig may be a plate material obtained by processing a wooden board or plywood instead of the steel sheet. Then, a pin may be provided on this plate material as a positioning projection instead of the claw. Pin diameter is 0.1-0.2mm
Something can be used. You may provide one pin or multiple pins corresponding to one nail. An insertion hole corresponding to the pin is formed in the reflector 15.

[0037]

As described above, according to the present invention, it is possible to easily and accurately assemble a removable backlight unit that can be inserted into and removed from a display device by using the light guide plate as a framework. Assembling the backlight unit requires only one jig and no special device is used, so the work is very easy. Moreover, since the screw is not used to determine the positional relationship between the reflector and the light guide plate, the cost of parts can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a backlight unit when assembled.

FIG. 2 is a front perspective view of the finished backlight unit.

FIG. 3 is a rear perspective view of the finished backlight unit.

FIG. 4 is a plan view of a reflector.

FIG. 5 is a cross-sectional view of the vicinity of a wall surface in a state where a reflector is laid on a jig.

FIG. 6 is a plan view showing a state in which the light guide plate is fitted with the projecting claws of the jig as a frame.

7 is a perspective view of part A (a) and part B (b) of FIG. 6. FIG.

FIG. 8 is a cross-sectional view of the vicinity of a wall surface in a state where a reflector, a light guide plate and a lamp are arranged on a jig.

FIG. 9 is a cross-sectional view of the vicinity of the wall surface in a state where the backlight is completed on the jig.

FIG. 10 is a front perspective view of a liquid crystal module.

FIG. 11 is a rear perspective view of the liquid crystal module.

FIG. 12 is a sectional view of the entire liquid crystal module (a) and a main part (b).

FIG. 13 is a perspective view showing a state where a backlight unit is taken out from the liquid crystal module.

[Explanation of symbols]

1 LCD module 10 backlight unit 11 lamps 12 lead wire 14 Light guide plate 15 reflector 15 holder 30 jigs 31 bottom 32 wall 33, 34, 35, 36 Projection claw

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) // F21Y 103: 00 F21Y 103: 00 (72) Inventor Tsutomu Fujita 3-201 Minamiyoshikata, Tottori City, Tottori Prefecture In Tottori Sanyo Electric Co., Ltd. (72) Inventor Katsumi Tanaka, 3-201 Minamiyoshikata, Tottori City, Tottori Prefecture Tottori Sanyo Electric Co., Ltd. (72) Inventor, Haku Aoki 3-201 Minamiyoshikata, Tottori City Tottori Sanyo Electric Co., Ltd. In-house F-term (reference) 2H091 FA14Z FA23Z FA41Z LA30

Claims (9)

[Claims] 1. A jig having a plurality of protruding claws on the bottom surface,
A sheet-like reflector having a hole through which the projection claw is inserted is laid, and a light guide plate is placed on the reflector so that the projection claw inserted into the hole of the reflector is fitted into the frame, and further the light guide plate of the light guide plate is inserted. After arranging the light source opposite to the side surface and bending the folding fold around the reflector so as to wrap the light source and adhering it to the upper surface of the light guide plate,
A method for assembling a backlight unit, wherein the jig is removed. 2. On a jig having protruding claws at the four corners of the bottom surface,
A sheet-like reflector having a hole through which the projection claw is inserted is laid, and a light guide plate is placed on the reflector so that the projection claw inserted into the hole of the reflector is fitted into the frame, and further the light guide plate of the light guide plate is inserted. The light sources are arranged opposite to each other on three side surfaces, the holder is arranged on the remaining one side surface, the lead wire of the light source is guided along the guide groove, and the three sides around the reflector are wrapped so as to wrap the light source. A backlight unit characterized by bending the folding white into a U-shape and adhering it to the upper surface of the light guide plate, and folding the remaining one side of the folding white and adhering it to the side surface of the holder, and then removing the jig. Assembly method. 3. The chamfered inclined sides are formed at two corners of the light guide plate, the step portions are formed at the remaining two corners, and the pair of protruding claws and the inclined sides are brought into contact with each other to form a remaining pair. 3. The method of assembling the backlight unit according to claim 2, wherein the protruding claw and the step are brought into contact with each other. 4. The bottom surface of the jig has a wall surface on three sides where the light source is arranged so as to facilitate bending of the folding fold of the reflector and to arrange the bent shape. Item 4. A method of assembling a backlight unit according to item 2 or 3. 5. The method of assembling a backlight unit according to claim 2, wherein the folding white has perforations at a bending position. 6. A structure of a backlight unit assembled on a jig having protruding claws at four corners, which has a hole into which the protruding claws are inserted and which can be bent into a U-shape on three sides. A reflector on a sheet on which a white is formed, a light guide plate which is placed on the reflector without rocking with the projecting claw inserted into the hole as a frame, and a light source which is arranged to face three side surfaces of the light guide plate. When,
A holder arranged on the other one side surface of the light guide plate;
A backlight including two lead wires that are connected to the light source and that are taken out to the back side of the light guide plate through the guide grooves in the longitudinal direction of the holder, and a connector connected to these lead wires. Unit structure. 7. The chamfered inclined sides are formed at two corners of the light guide plate, the step portions are formed at the remaining two corners, and the pair of protruding claws and the inclined sides are brought into contact with each other to form a remaining pair. 7. The structure of the backlight unit according to claim 6, wherein the protruding claw and the stepped portion are brought into contact with each other. 8. The structure of the backlight unit according to claim 6, wherein the folding screen has a perforation at a bending position. 9. A display device, comprising: a display device main body; and a backlight unit that is slid into and removed from the main body through an insertion opening of the main body, wherein the backlight unit includes a light guide plate and the light guide plate. A light source disposed on a side surface of the light plate, and a reflector that covers the back surface of the light guide plate and encloses the light guide plate and the light source and is adhered to an upper surface of the light guide plate are provided. The display device is characterized in that an insertion hole is formed through which the projection of (1) can be inserted in a direction perpendicular to the sliding direction of the backlight unit.