KR20240037395A - Light assembly fixing structure of backlight unit - Google Patents

Abstract

The present invention relates to a fixing structure for a light source module used as a backlight light source of a display device. This embodiment relates to a light source fixing structure for a direct backlight device in which a light source module with multiple light sources mounted on a substrate is fixed inside the cover bottom. In the structure, the cover bottom includes a first fastening protrusion protruding upward from the bottom surface, and a second fastening protrusion protruding upward from the floor surface at a position spaced apart from the first fastening protrusion, and the light source module includes: It includes a first fastening groove formed in the substrate at a position corresponding to the first fastening protrusion, and a second fastening groove formed while providing an insertion hole in the width direction of the substrate at a position corresponding to the second fastening protrusion, After the first fastening protrusion is inserted into the first fastening groove and fastened, the second fastening protrusion is inserted into the second fastening groove through the insertion hole and fastened by rotation of the substrate, thereby achieving fixation.

Description

Light source fixing structure of backlight device {Light assembly fixing structure of backlight unit}

The present invention relates to a display device, and more specifically, to a structure for fixing a light source module used as a backlight light source of a display device.

Unlike other display devices, the Liquid Crystal Display Device (LCD), a flat display device, does not emit light on its own and therefore requires a separate external light source to produce an image. Therefore, the LCD further includes a backlight device as an external light source in addition to the liquid crystal panel, and the backlight device uniformly supplies a high-brightness surface light source to the liquid crystal panel, thereby realizing high-quality images.

As such, backlight devices refer to lighting devices for realizing images on display devices such as LCDs, and are classified into direct lighting type or edge lighting type backlight devices depending on the location of the light source. The direct backlight device illuminates the liquid crystal panel by directly emitting light from the lower light source through the diffusion plate and optical sheet, while the side-type backlight device indirectly illuminates the liquid crystal panel from the light source on the side through the light guide plate and optical sheet. It is a method of illuminating and illuminating.

As a light source for backlight devices, light emitting diodes (hereinafter referred to as 'LEDs') are mainly used, which have advantages such as small size, low power consumption, and high reliability.

Figure 1 is an exploded perspective view showing a direct backlight device according to the prior art, and Figure 2 is a cross-sectional view showing the fixing structure of the light source module, which is the main part of Figure 1.

As can be seen in Figure 1, the direct backlight device has a plurality of light source modules 20 mounted on the inner surface of a square plate-shaped cover bottom 10, and a diffusion plate 30 and a prism are placed on the upper side of the light source module 20. The sheets 40 are stacked, and the guide panel 50 is fastened to the cover bottom 10 on the upper side of the prism sheet 40.

Here, the light source module 20 forms an LED array by fastening a plurality of LED packages 22 at regular intervals on a strip-shaped substrate 21 having a predetermined width and length.

This light source module 20 is fixed to the inner surface of the cover bottom 10, and the light source module 20 is fixed to the cover bottom 10 through a double-sided tape 23, as shown in (a) of Figure 2. It is fixedly attached or fixedly fastened to the cover bottom 10 via a screw 24 as shown in (b).

The method of fixing the light source module 20 using double-sided tape 23 has the advantage of easy assembly of the light source module. However, if a defect occurs in the LED package 22 and the light source module 20 must be replaced, the substrate 21 ) is not easily separated from the cover bottom (10) and thus cannot be replaced.

In addition, the method of fixing the light source module 20 using the screw 24 has the advantage of being able to easily separate the light source module 20 from the cover bottom 10 when the LED package 22 is defective, but it does not constitute an LED array. Since a plurality of screws 24 must be fastened to one light source module 20, there is a problem in that the assembly process of the light source module becomes complicated due to fastening a large number of screws.

In order to solve this problem, the present applicant introduced 'light source fixing structure of backlight device' in Korean Patent Publication No. 10-2016-0053439. The light source fixing structure of the prior patent document forms a cover bottom fastening part, wherein the fastening part includes a vertical part bent upward where a part of the bottom surface of the cover bottom is cut, and an extension part bent again in the horizontal direction from the top of the vertical part and extending. And, the end of the extension part consists of a locking part that protrudes downward.

The fastening part of the prior patent document is easy to fasten and has the effect of stably fixing the substrate of the light source module. However, since it must be formed by cutting the bottom surface of the cover bottom made of aluminum and repeating the process of bending it several times, shape processing is required. This is so difficult that it cannot be applied in practice.

Korean Patent Publication No. 10-2016-0053439

The present invention was proposed to solve the above problems. In a direct-type backlight device, the PCB board constituting the light source module is fixed to the cover bottom, and the light source fixing structure of the backlight device is easy to process and assemble. The task is to provide.

Additionally, the present invention aims to provide a light source fixing structure for a backlight device in which a light source module can be stably fixed to the cover bottom in a direct-type backlight device.

This embodiment to solve the above problem is a light source fixing structure of a direct backlight device in which a light source module with a plurality of light sources mounted on a substrate is fixed inside the cover bottom, and the cover bottom is located on the upper side of the bottom surface. It includes a first fastening protrusion protruding, and a second fastening protrusion protruding upward from the bottom surface at a position spaced apart from the first fastening protrusion, wherein the light source module is attached to the substrate at a position corresponding to the first fastening protrusion. A first fastening groove is formed, and a second fastening groove is formed while providing an insertion hole in the width direction of the substrate at a position corresponding to the second fastening protrusion, and the first fastening protrusion is connected to the first fastening groove. After the substrate is inserted and fastened, the second fastening protrusion is inserted through the insertion hole into the second fastening groove through the insertion hole and fastened to the second fastening groove, thereby fixing the substrate.

Additionally, the first fastening protrusion may be formed at the center of the bottom surface of the cover bottom in the longitudinal direction of the light source module.

Additionally, one or more pairs of the second fastening protrusions may be formed at positions spaced apart from the first fastening protrusions by a predetermined distance on both sides of the light source module in the longitudinal direction.

Additionally, the second groove may have a guide protrusion through which the substrate in the insertion hole area protrudes toward the insertion hole.

Additionally, the guide protrusion may have a convex curved shape.

In addition, the shortest width (w2) of the insertion hole formed by the guide protrusion will be formed at a ratio of 85% to 95% (0.85*w1≤w2≤0.95*w1) compared to the width (w1) of the second groove. You can.

Additionally, the tip width (w3) of the insertion hole may be formed to be larger than the width (w1) of the second groove.

Additionally, the tip width (w3) of the insertion hole may be formed at a ratio of 105% to 115% (1.05*w1≤w3≤1.15*w1) compared to the width (w1) of the second fastening groove 212.

In the present invention, the fastening means between the cover bottom and the light source module has a simple protrusion structure and a groove structure, which has the effect of making the fastening means very easy to process.

In addition, the present invention has the effect of making assembly very easy by fastening the cover bottom and the light source module through simple insertion and rotation operations.

Additionally, the present invention has the effect of stably fixing the light source module to the cover bottom even after assembly.

1 is an exploded perspective view showing a direct backlight device according to the prior art;
Figure 2 is a cross-sectional view showing the fixing structure of the light source module, which is the main part of Figure 1;
Figure 3 is an exploded perspective view showing a direct backlight device according to this embodiment;
4 is a plan view showing the assembled state of the light source module according to this embodiment;
Figure 5 is an enlarged view showing the detailed configuration of the second fastening groove, which is the main part of Figure 4;
Figure 6 is a cross-sectional view showing the assembled state of the light source module according to this embodiment;
Figure 7 is a process chart showing the assembly process of the light source module according to this embodiment.

The technical problems achieved by the present invention and its implementation will become clear by the preferred embodiments described below. Hereinafter, preferred embodiments of the present invention will be examined in detail with reference to the attached drawings.

It should be understood that the differences in this embodiment, described later, are not mutually exclusive. That is, without departing from the spirit and scope of the present invention, the specific shape, structure, and characteristics described may be implemented in other embodiments with respect to one embodiment, and the positions of individual components within each disclosed embodiment. Alternatively, it should be understood that the arrangement may be changed, and similar reference signs in the drawings refer to the same or similar functions across various aspects, and the length, area, thickness, etc. may be exaggerated for convenience. In the description of this embodiment, expressions such as top, bottom, left, right, vertical, horizontal, first, second, etc. indicate relative positions, directions, and orders, and their technical meaning is not limited by dictionary meaning. will be.

Figure 3 is an exploded perspective view showing a direct backlight device according to this embodiment, Figure 4 is a plan view showing the assembled state of the light source module according to this embodiment, and Figure 5 is a detail of the second fastening groove, which is the main part of Figure 4. It is an enlarged view showing the configuration, Figure 6 is a cross-sectional view showing the assembly state of the light source module according to this embodiment, and Figure 7 is a process diagram showing the assembly process of the light source module according to this embodiment.

First, referring to FIG. 3, the backlight device of this embodiment includes a cover bottom 100, a light source module 200 mounted on the inner surface of the cover bottom, and a diffusion plate ( 300), a prism sheet 400, and a guide panel 500 fastened to the cover bottom 100 on the upper side of the prism sheet 400. Additionally, the backlight device may further include a reflective sheet (not shown) mounted on the inner surface of the cover bottom 100 below the light source module 200.

The cover bottom 100 has a hexahedral shape with an open top and forms the rear housing of the backlight device, and forms a space inside where the light source is stored. The cover bottom 100 can be formed by forming a square plate made of metal through a press process.

The light source module 200 constitutes an array in which a plurality of LED chips (not shown) are mounted at regular intervals on a substrate 210. A plurality of light source modules 200 are disposed within the cover bottom 100 according to the size of the backlight device.

The substrate 210 is printed with a predetermined circuit for driving the LED chip, and forms a strip shape with a predetermined width and length. A silver LED lens 220 is fastened to the top of each LED chip, and the light emitted from the LED chip passes through the LED lens 220 and is spread to a wide beam angle. The LED lens 220 may have a hemispherical dome shape.

The diffusion plate 300 is a light control element that diffuses light from a plurality of point light sources incident from the light source module 200 so that light of uniform brightness is emitted upward. The diffusion plate 300 is made of a transparent or translucent resin. For example, it may be made of a resin such as polymethylmethacrylate (PMMA), poly styrene (PS), meta styrene (MS), or polycarbonate (PC).

The prism sheet 400 is a light control element that controls the emission angle so that the diffused light passes in the vertical direction while passing through the diffusion plate 300. The light passing through the diffusion plate 300 exhibits a wide beam angle, and the prism sheet 400 controls the exit angle so that the light passing through the diffusion plate 300 travels in the vertical direction, so that the backlight device emits high brightness from the front. so that it can be displayed. This prism sheet 400 may be composed of a pair of sheets with a prism pattern formed on the lower surface, and each sheet is disposed on the upper and lower parts so that the prism patterns are orthogonal to each other.

In addition, a wavelength conversion sheet for converting the light of the LED chip into white light may be further laminated on the diffusion plate 300 depending on the type of LED chip, and optical sheets with various functions may be laminated as needed.

The guide panel 500 is fastened along the edge of the cover bottom 100 at the top of the prism sheet 400 to fix the diffusion plate 300 and the prism sheet 400 to the cover bottom 100. This guide panel 600 forms a square frame shape with an open center so that light from a surface light source can be emitted.

In the direct backlight device configured as described above, the light emitted from the LED chip of the light source module 200 is radially diffused as it passes through the LED lens 220, and is then connected to the upper diffusion plate 300 and prism sheet 400. As it passes through, it is converted into a surface light source and illuminates the liquid crystal panel (not shown).

Meanwhile, the backlight device of the present invention has a structure in which the light source module 200 is assembled and fixed to the cover bottom 100 by fastening means provided on the cover bottom 100 and the substrate 210. The backlight device for this purpose has a fastening means having a protrusion structure formed on the cover bottom, and a fastening means having a hole or groove structure formed on the substrate. Below, the assembly structure of the cover bottom and the light source module will be examined in detail according to embodiments.

Referring to Figures 3 and 4, the cover bottom 100 is formed with circular first fastening protrusions 110 and second fastening protrusions 120, respectively, on the bottom surface of the light source module 200.

The first fastening protrusion 110 may be formed at the center (C) of the cover bottom 100 in the longitudinal direction of the light source module 200 to be assembled, and is fastened to the first fastening groove 211 of the substrate 210. This comes true. The first fastening protrusion 110 functions as a rotation axis that allows the substrate 210 to rotate around the first fastening protrusion 110 after it is fastened.

The second fastening protrusion 120 may be formed at a position spaced apart from the first fastening protrusion 110 by a predetermined distance in both side directions with respect to the longitudinal direction of the assembled light source module 200. Accordingly, the second fastening protrusions 120 may be formed in at least one pair and are fastened to the second fastening grooves 212 of the substrate 210.

The first and second fastening protrusions 110 and 120 may be formed through a punching process on the bottom surface of the cover bottom 100, and may each have a predetermined diameter and height. In addition, since the first and second fastening protrusions 110 and 120 are formed to correspond to the positions where the light source modules 200 are assembled, a plurality of the first and second fastening protrusions 110 and 120 are formed in the width direction according to the number of light source modules 200.

And the light source module 200 has first and second fastening grooves 211 and 212 corresponding to the first and second fastening protrusions 110 and 120 formed on the substrate 210.

The first fastening groove 211 may be formed at the center C of the longitudinal substrate 210 and is fastened to the first fastening protrusion 110 of the cover bottom 100. Accordingly, the substrate 210 can rotate around the first fastening protrusion 110 while the first fastening protrusion 110 is inserted into the first fastening groove 211 .

The first fastening groove 211 may have a groove or hole structure and have a predetermined inner diameter. The first fastening protrusion 110 may be configured to be inserted into the first fastening groove 211 by interference fitting, and for this purpose, the first fastening groove 211 may have an inner diameter equal to the outer diameter of the first fastening protrusion 110. You can.

The second fastening groove 212 may be formed at a position spaced apart from the first fastening groove 211 by a predetermined distance in both side directions with respect to the substrate 210 in the longitudinal direction. That is, the second fastening grooves 212 are formed in at least one pair at positions corresponding to the second fastening protrusions 120, and are fastened to the second fastening protrusions 120 of the cover bottom 100.

The second fastening groove 212 is formed by opening a portion of the substrate 210 in the width direction and provides an insertion hole 213 into which the second fastening protrusion 120 is inserted in the width direction. In particular, the second fastening groove 212 is formed at a position symmetrical about the first fastening groove 211, and the second fastening groove 212 on one side and the second fastening groove 212 on the other side are connected to the substrate ( Insertion holes 213 are provided in different directions with respect to the width direction of 210). For example, as shown in FIG. 4, the second fastening groove 212 on one side has an insertion hole 213 formed on the upper side of the substrate 210, and the second fastening groove 212 on the other side has an insertion hole 213 formed on the upper side of the substrate 210. An insertion hole 213 is formed on the lower side of the substrate 210 . Accordingly, as the substrate 210 rotates around the first fastening protrusion 110, the second fastening protrusions 120 on both sides can be inserted into the second fastening groove 212 and fastening can be performed.

The second fastening groove 212 may have an inner diameter equal to the outer diameter of the second fastening protrusion 120.

Meanwhile, referring to FIG. 5, the insertion hole 213 of the second fastening groove 212 is provided with a guide protrusion 214 to guide the insertion of the second fastening protrusion 120 and prevent the inserted second fastening protrusion 120 from coming off. ) is formed by protruding. The guide protrusion 214 is preferably formed in a convex curved shape so that it can slide while in contact with the second fastening protrusion 120.

The width (w2) of the insertion hole 213 is formed to be somewhat smaller than the width (w1, i.e., inner diameter) of the second fastening groove 212 by the guide protrusion 214 protruding toward the insertion hole 213 (w2<w1). . Therefore, the second fastening protrusion 120 is inserted and fastened into the second fastening groove 212 along the insertion hole 213 of a narrow width (w2) by force forced from an external force, and after fastening, the guide protrusion 214 It is fixed so that it does not come off.

At this time, the width (w2) of the insertion hole 213 is preferably formed at a ratio of 85% to 95% compared to the width (w1) of the second fastening groove 212 (0.85*w1≤w2≤0.95*w1). , if formed with a width of less than 85%, the second fastening protrusion 120 may not be inserted, and if formed with a width exceeding 95%, the separation prevention effect may not appear. In this embodiment, the width w2 of the insertion hole 213 is formed at a ratio of 90% compared to the width w1 of the second fastening groove 212. For example, the second fastening groove 212 is 0.5 mm. It is formed with a width w1 of , and the insertion hole 213 is formed with a width w2 of 0.45 mm.

On the other hand, the tip width (w3) of the insertion hole 213 is slightly larger than the width (w1) of the second fastening groove 212 so that the second fastening protrusion 120 can be easily inserted and fastened. It is desirable to form a large size (w3>w1). When the second fastening protrusion 120 is inserted into the second fastening groove 212 due to the rotation of the substrate 210, curvature occurs depending on the distance between the central axis and the second fastening protrusion 120. At this time, the rotation Due to the curvature, the second fastening protrusion 120 may interfere with the edge of the tip of the insertion hole 213, thereby preventing insertion. Accordingly, the width of the tip of the insertion hole 213 is formed to be somewhat large, so that when the substrate 210 is rotated, the second fastening protrusion 120 is easily inserted into the second fastening groove 212 without interfering with the corner of the insertion hole 213. It can be.

At this time, the tip width (w3) of the insertion hole 213 is preferably formed at a ratio of 105% to 115% compared to the width (w1) of the second fastening groove 212 (1.05*w1≤w3≤1.15*w1 ), if formed with a width of less than 105%, the effect of preventing interference is almost non-existent, and if formed with a width exceeding 115%, the durability of the substrate may be reduced. In this embodiment, the tip width (w3) of the insertion hole 213 is formed at a ratio of 110% compared to the width (w1) of the second fastening groove 212. For example, the second fastening groove 212 is 0.5%. It is formed with a width w1 of mm, and the tip of the insertion hole 213 is formed with a width w3 of 0.55 mm.

Additionally, referring to FIG. 6, a cutout portion 121 may be formed on one side of the second fastening protrusion 120. The end of the substrate 210 in the area of the second fastening groove 212 is inserted into the incision 121, and the upper end of the second fastening protrusion 120 presses the end of the substrate 210 to fasten the substrate 210. This ensures stable contact with the bottom surface of the cover bottom (100). Accordingly, the substrate 210 is prevented from lifting or flowing upward, so that the assembly can be stably fixed.

Looking at the assembly process of the light source module 200 with reference to FIG. 7, first, the substrate 210 is inserted so that the first fastening protrusion 110 of the cover bottom 100 is inserted into the first fastening groove 211 as shown in (a). conclude. The first fastening protrusion 110 and the first fastening groove 211 are fastened in the vertical direction. At this time, since the second fastening protrusion 120 and the second fastening groove 212 must be avoided so as not to overlap each other in the vertical direction, the substrate 210 is tilted at a predetermined angle with respect to the horizontal direction in which final assembly is performed. Fastening is performed in the vertical direction.

After the first fastening protrusion 110 and the second fastening groove 212 are completely fastened and the substrate 210 is in close contact with the bottom surface of the cover bottom 100, the substrate 210 is tilted in an inclined direction as shown in (b). Rotate the first fastening protrusion 110 in the horizontal direction about the central axis. At this time, the left region of the substrate 210 rotates upward and the right region rotates downward, and the second fastening protrusions 120 on the left and right sides are inserted into the second fastening grooves 212, respectively. In the process of rotating the substrate 210 in this way, the second fastening protrusion 120 is additionally fastened by the second fastening groove 212, thereby completing the assembly of the light source module.

As in this embodiment, the light source module can be easily assembled to the cover bottom by the above-described fastening means and fastening process formed on the cover bottom and the substrate, and can be stably fixed even after assembly.

Although exemplary embodiments of the present invention have been shown and described as described above, various modifications and other embodiments will occur to those skilled in the art. These modifications and other embodiments are to be considered and included in the appended claims without departing from the true spirit and scope of the present invention.

100: Cover bottom 110: First fastening protrusion
120: second fastening protrusion 121: cutout
200: light source module 210: substrate
211: first fastening groove 212: second fastening groove
213: Insertion hole 214: Guide protrusion
300: diffusion plate
400: Optical sheet
500: Guide panel

Claims (8)

In the light source fixing structure of a direct backlight device in which a light source module with a plurality of light sources mounted on a substrate is fixed inside the cover bottom,
The cover bottom is,
It includes a first fastening protrusion protruding upward from the floor surface, and a second fastening protrusion protruding upward from the floor surface at a position spaced apart from the first fastening protrusion,
The light source module is,
a first fastening groove formed in the substrate at a position corresponding to the first fastening protrusion;
It includes a second fastening groove formed while providing an insertion hole in the width direction of the substrate at a position corresponding to the second fastening protrusion,
After the first fastening protrusion is inserted into the first fastening groove and fastened, the second fastening protrusion is inserted into the second fastening groove through the insertion hole and fastened by rotation of the substrate.
Light source fixing structure of the backlight device. According to claim 1,
The first fastening protrusion is formed at the center of the bottom surface of the cover bottom in the longitudinal direction of the light source module. According to claim 2,
The light source fixing structure of the backlight device, wherein one or more pairs of the second fastening protrusions are formed at positions spaced apart from the first fastening protrusions by a predetermined distance on both sides of the light source module in the longitudinal direction. According to claim 1,
The light source fixing structure of a backlight device, wherein the second groove includes a guide protrusion through which the substrate in the insertion hole area protrudes toward the insertion hole. According to claim 4,
A light source fixing structure for a backlight device, wherein the guide protrusion has a convex curved shape. According to claim 5,
The shortest width (w2) of the insertion hole formed by the guide protrusion is formed at a ratio of 85% to 95% (0.85*w1≤w2≤0.95*w1) compared to the width (w1) of the second groove. Light source fixing structure of the device. According to claim 1,
A light source fixing structure for a backlight device, wherein the tip width (w3) of the insertion hole is formed to be larger than the width (w1) of the second groove. According to claim 7,
The light source of the backlight device, wherein the tip width (w3) of the insertion hole is formed at a ratio of 105% to 115% (1.05*w1≤w3≤1.15*w1) compared to the width (w1) of the second fastening groove 212. Fixed structure.

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