WO2012053413A1

WO2012053413A1 - Lighting device and liquid-crystal display device

Info

Publication number: WO2012053413A1
Application number: PCT/JP2011/073510
Authority: WO
Inventors: 達朗黒田
Original assignee: シャープ株式会社
Priority date: 2010-10-20
Filing date: 2011-10-13
Publication date: 2012-04-26

Abstract

The present invention provides: a lighting device that efficiently dissipates heat generated by a light-emitting element, minimizing decreases in the service life and emission efficiency of said light-emitting element; and a liquid-crystal display device provided with said lighting device. This lighting device is provided with a substrate to which a light-emitting element is attached, a heatsink, and a substrate anchor plate. The substrate is attached to one surface of the heatsink, and the substrate anchor plate is attached to the surface of the heatsink opposite the surface to which the substrate is attached. The lighting device is also provided with a heat-dissipating columnar member fitted into through-holes provided in the substrate and the heatsink. The surfaces of said heat-dissipating columnar member in contact with the substrate and the heatsink are smooth.

Description

Illumination device and liquid crystal display device

The present invention relates to a lighting device and a liquid crystal display device. More specifically, the present invention relates to a lighting device and a liquid crystal display device that suppress deterioration in performance and lifetime due to heat generation of a light emitting diode element.

The illumination device is a device that emits light, and is used in a display device using a non-self-luminous display element. For example, it is used in a liquid crystal display device using a liquid crystal display element. Since the liquid crystal display element is a non-self-luminous display element, in the liquid crystal display device, it is necessary to irradiate the liquid crystal display element with illumination light from a lighting device (backlight). Such a liquid crystal display device is indispensable as a means for displaying information and images. For example, in recent years, portable information terminals represented by cellular phones and PDAs (Personal Digital Assistants). Devices are widely used, and a liquid crystal display panel having advantages such as thinness, light weight, and low power consumption is used as the display panel.

In a backlight used in a conventional liquid crystal display device, a cold cathode tube has been used as a light source. However, in recent years, since it is excellent in terms of small size, low power consumption, etc., a light emitting diode (hereinafter, “ LED "or" LED element ") is mainly used.

By the way, in the illuminating device which uses a LED element as a light source, with the temperature rise by the heat_generation | fever from a LED element, while the lifetime characteristic of a LED element deteriorates, luminous efficiency falls and it becomes difficult to ensure required light quantity. May occur. In particular, in the illumination device used in the above-described liquid crystal display device, it is required to make the illumination device thinner and smaller, but this makes it difficult to further release the heat generated from the LED element, and the lifetime of the LED element. There is a risk of deteriorating characteristics and reducing luminous efficiency.

With regard to this point, it is conceivable to make a structure with good heat dissipation to suppress the temperature rise of the LED element, specifically, heat dissipation with good thermal conductivity on both sides of the wiring board on which the LED element is mounted. There has been proposed an LED backlight in which a body is provided and the radiator is in direct contact with the frame (see, for example, Patent Document 1). FIG. 15 is a schematic cross-sectional view of an LED backlight according to Patent Document 1. As shown in FIG. 15, in the LED backlight, the LED light source 110 is provided on the wiring board 115, and a first heat radiator 122 is arranged on the back surface of the wiring board 115, Is provided with a second radiator 123. The first radiator 122 and the second radiator 123 are arranged so as to contact the frame 124. Thereby, the heat generated from the LED light source 110 is efficiently transmitted to the

radiators

122, 123 and the frame 124. As a result, the heat from the LED element can be efficiently radiated outside the LED backlight.

JP 2006-216244 A

However, even the LED backlight according to Patent Document 1 described above cannot sufficiently dissipate the heat generated from the LED element, which may lead to deterioration in the life characteristics of the LED element and reduction in light emission efficiency. There was room for improvement.

The present invention has been made in view of the above situation, and efficiently radiates heat generated from a light-emitting element, and suppresses deterioration of life characteristics and light emission efficiency of the light-emitting element and a liquid crystal including the same. The object is to provide a display device.

The present inventor has conducted extensive studies on the above-mentioned problems. As a result, even if a plate-like heat radiator (hereinafter, also referred to as a heat sink) is used, the reason why the heat generated from the light-emitting element cannot be sufficiently dissipated is the light emission. It has been found that the circuit board (hereinafter also referred to as a substrate) to which the element is attached has a low thermal conductivity. For this reason, the heat accumulated on the substrate is not sufficiently transmitted to the heat sink attached to the substrate, and continues to be accumulated on the substrate. As a result, the life characteristics of the light emitting element are deteriorated and the light emission efficiency is lowered. Based on this cause, the present inventor further studied, and as a result, a hole is formed in the substrate and the heat radiating plate, and a columnar heat radiating body (hereinafter, also referred to as a heat radiating columnar member) having a high thermal conductivity. The heat accumulated in the substrate is further transferred to the heat dissipation plate via the heat dissipation columnar member, and as a result, the heat generated from the light emitting element is dissipated more efficiently, and the life characteristics of the light emitting element The inventors have arrived at the present invention by conceiving that deterioration of light emission and reduction in luminous efficiency can be suppressed.

That is, one aspect of the present invention is a lighting device including a substrate to which a light emitting element is attached, a heat radiating plate, and a substrate fixing plate, and the substrate is attached to one surface of the heat radiating plate. The substrate fixing plate is attached to a surface of the heat radiating plate opposite to the surface to which the substrate is attached, and the lighting device is a heat radiating member fitted in a through hole provided in the substrate and the heat radiating plate. A columnar member for heat dissipation, and the columnar member for heat dissipation is a lighting device in which a surface in contact with the substrate and the heat dissipation plate has a smooth surface. Hereinafter, this form is also referred to as a first form.

The heat-dissipating columnar member includes a core structure having no cavity inside and a tubular structure having a through hole inside.

In addition, according to the first embodiment, since the smooth heat radiating columnar member is fitted into the through hole, the heat radiating columnar member can be easily attached, and the heat radiating columnar member can be attached to the substrate or the heat radiating plate. It can prevent damage.

The configuration of the lighting device is not particularly limited by other components as long as such components are formed as essential.

Hereinafter, the preferable form of the said illuminating device is demonstrated in detail.

In the first embodiment, the illumination device further includes a light guide plate, and the substrates are arranged in a pair with the light guide plate interposed therebetween, and the heat radiation columnar member and the other of the one of the pair of substrates. It is preferable that the light emitting element of the substrate is disposed so as to be opposed, and the light emitting element of the one substrate and the columnar member for heat dissipation of the other substrate are disposed so as to be opposed. Thereby, since the light emitting element and the columnar member for heat dissipation are respectively arranged in the opposing arrangement of the pair of substrates, the light from the light emitting element can be uniformly irradiated onto the light guide plate.

In the first embodiment, it is preferable that the heat radiating columnar member is further fitted into a through hole provided in the substrate fixing plate. Hereinafter, this form is also referred to as a second form. As a result, the heat accumulated in the substrate can be efficiently transmitted not only to the heat radiating plate but also to the substrate fixing plate, so that the heat generated from the light emitting element can be radiated more efficiently, and the life characteristics of the light emitting element are deteriorated. A decrease in luminous efficiency can be further suppressed. Moreover, since the columnar member for heat dissipation can play a role of fixing the substrate, the heat dissipation plate, and the substrate fixing plate, it is not necessary to fix them with screws or the like, and it becomes possible to save members and labor. .

2nd form WHEREIN: It is preferable that the said columnar member for heat dissipation has a collar in one terminal part. Hereinafter, this form is also referred to as a third form. Thereby, it can prevent that a board | substrate falls out from the columnar member for heat dissipation.

The collar refers to a planar structure formed substantially perpendicular to the extending direction of the heat radiating columnar member. More specifically, the term “substantially perpendicular” here refers to an angle of 85 ° to 90 ° with respect to the extending direction of the columnar member for heat dissipation.

The heat radiating columnar member may be formed in a tapered shape. Also by this, it can prevent that a board | substrate, a heat sink, and a board | substrate fixing plate fall out from the columnar member for heat dissipation.

In the third embodiment, it is preferable that the heat radiating columnar member is a circular tube, and the other end portion of the heat radiating columnar member is bent outward after being fitted into the substrate fixing plate. Thereby, a board | substrate, a heat sink, and a board | substrate fixing plate can be fixed more firmly by the columnar member for heat dissipation.

In the third embodiment, it is preferable that the heat radiating columnar member is a circular tube, and the other end portion of the heat radiating columnar member is a member whose pressure is increased after fitting into the substrate fixing plate and the diameter thereof is widened. . Thereby, it becomes possible to fix a board | substrate, a heat sink, and a board | substrate fixing plate still more firmly by the columnar member for heat dissipation. Moreover, since the adhesiveness between the columnar member for heat dissipation and the substrate fixing plate is improved by the pressure, the thermal conductivity from the columnar member for heat dissipation to the substrate fixing plate is further improved.

In the second embodiment, the heat radiating columnar member is a circular core having a slit formed at one end portion, and the circular core on the side on which the slit is formed has a flange, and the heat radiating columnar member The other end of the member preferably has a collar. Thereby, it becomes possible to firmly fix the substrate, the heat radiating plate, and the substrate fixing plate by the heat radiating columnar member, and the columnar structure for heat radiation once attached by elastically deforming the columnar structure having the slit portion. It is also possible to remove the member.

The said collar part means the nail | claw-shaped folding structure by which the front-end | tip was notched.

Another aspect of the present invention is a liquid crystal display device that includes a liquid crystal sealed between a pair of substrates disposed opposite to each other, and also includes the illumination device. As a result, the heat accumulated in the LED substrate is sufficiently transmitted to the heat radiating plate through the heat radiating columnar member, and as a result, the heat generated from the LED element is efficiently radiated, the deterioration of the life characteristics of the LED element and the light emission. Reduction in efficiency can be suppressed.

The configuration of the liquid crystal display device is not particularly limited by other components as long as such components are essential.

According to the illumination device and the liquid crystal display device, the heat accumulated in the substrate can be transmitted to the heat dissipation plate through the heat dissipation columnar member, so that the heat generated from the light emitting element can be radiated more efficiently. In addition, it is possible to suppress the deterioration of the life characteristics of the light emitting element and the decrease in light emission efficiency.

1 is a schematic plan view of a liquid crystal display device according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the liquid crystal display device taken along line A1-A2 shown in FIG. FIG. 3 is a schematic plan view of the LED element of the liquid crystal display device according to Embodiment 1 and the surrounding structure. It is a side surface schematic diagram of the LED element of the liquid crystal display device which concerns on Embodiment 1, and its surrounding structure. FIG. 3 is a schematic top view of the LED element of the liquid crystal display device according to Embodiment 1 and the surrounding structure. It is a plane schematic diagram of the LED element with which the liquid crystal display device which concerns on Embodiment 2 is equipped, and its periphery structure. FIG. 6 is a schematic top view of an LED element included in a liquid crystal display device according to Embodiment 2 and a surrounding structure. It is a plane schematic diagram of the LED element with which the liquid crystal display device which concerns on Embodiment 3 is equipped, and its periphery structure. It is an upper surface schematic diagram of the LED element with which the liquid crystal display device which concerns on Embodiment 3 is provided, and its periphery structure. FIG. 6 is a schematic view according to a modification of the heat radiating columnar members of the first to third embodiments. It is a cross-sectional schematic diagram of the columnar member for heat dissipation with which the liquid crystal display device which concerns on Embodiment 4 is provided. It is a schematic diagram which shows the process of deforming the columnar member for heat dissipation of FIG. It is a cross-sectional schematic diagram which shows the columnar member for heat dissipation of FIG. 9 deform | transformed by the process of FIG. It is a cross-sectional schematic diagram which shows the columnar member for heat dissipation of FIG. 9 deform | transformed by the process different from FIG. It is the upper surface and side surface schematic diagram of the columnar member for heat dissipation with which the liquid crystal display device which concerns on Embodiment 7 is provided. It is a cross-sectional schematic diagram which shows a mode that the columnar member for heat dissipation of FIG. 13 is attached to LED board etc. It is a cross-sectional schematic diagram of the LED backlight which concerns on patent document 1. FIG.

Embodiments will be described below, and the present invention will be described in more detail with reference to the drawings. However, the present invention is not limited to these embodiments.

Embodiment 1
Hereinafter, the illumination device and the liquid crystal display device according to Embodiment 1 will be described in detail with reference to FIGS. 1 to 3-3. FIG. 1 is a schematic plan view of a liquid crystal display device according to Embodiment 1, and FIG. 2 is a schematic cross-sectional view of the liquid crystal display device taken along line A1-A2 shown in FIG. -3 is a schematic plan view, a schematic side view, and a schematic top view of the LED element of the liquid crystal display device according to Embodiment 1 and the surrounding structure. The illumination device according to the first embodiment includes a light guide plate 5, an optical sheet 6, a plurality of LED elements 10, an LED substrate 11, a heat radiating plate 12, an LED substrate fixing plate 13, screws 14 and 15, and a heat radiating columnar member 31. Is done. The liquid crystal display device according to the first embodiment includes the lighting device, the support member 16, and the liquid crystal panel 30. The plurality of LED elements 10 are mounted on an LED substrate 11, and a heat radiating plate 12 is attached to the back side of the LED substrate 11. The LED board 11 includes a power connector 17 that connects wiring for connecting to a power source. Further, the LED board fixing plate 13, the heat radiating plate 12, and the LED board 11 are fixed by screws 14. The LED board 11 and the heat radiating plate 12 are provided with through holes, and a plurality of heat radiating columnar members 31 are fitted into the through holes. The LED substrate fixing plate 13 has two surfaces that are perpendicular to each other, and the heat radiating plate 12 is attached to one surface of the two surfaces. Further, the LED board fixing plate 13 is fixed to the support member 16 with screws 15 through the other surface. The light guide plate 5 is mounted on the support member 16 so that the light incident surface is disposed at a position facing the plurality of LED elements 10. An optical sheet 6 is disposed on the upper surface of the light exit surface of the light guide plate 5. Further, the liquid crystal panel 30 is attached on the optical sheet 6.

As shown in FIG. 1, the LED substrate 11 and the LED substrate 41 are arranged with the light guide plate 5 interposed therebetween, and the heat dissipation columnar member 31 attached to the LED substrate 11 and the LED attached to the LED substrate 41. The element 10 is disposed opposite to the element 10. Further, the LED element 10 attached to the LED substrate 11 and the heat dissipating columnar member 31 attached to the LED substrate 41 are arranged to face each other. As a result, light from the LED element 10 attached to the LED board 41 is emitted to a region where the LED element 10 attached to the LED board 11 cannot emit light sufficiently, and the LED attached to the LED board 41 Since light from the LED element 10 attached to the LED substrate 11 is emitted to a region where the element 10 cannot emit light sufficiently, the light guide plate 5 can be irradiated with light uniformly. In addition, LED board |

substrates

11 and 41 may each differ in arrangement | positioning of LED element 10, and arrangement | positioning of LED element 10 is the same, and after arrange | positioning so that a structural member may mutually oppose, one board | substrate is attached. It may be shifted from the front to the side and used in a staggered arrangement.

As the LED element 10 that is a light source, a white LED element may be used, or LED elements of three colors of red, blue, and green may be appropriately combined and used. The light guide plate 5 is a member that takes in light emitted from the LED element 10 as a light source from a light incident surface and emits light substantially uniformly from a light output surface having a larger area than the light incident surface. Light incident on the light incident surface of the light guide plate 5 repeats surface reflection in the light guide plate 5 and spreads in the light guide plate 5. When light hits a reflective dot (not shown) provided on the light guide plate 5, the light is scattered there and emitted from the light exit surface of the light guide plate. The LED board 11 is a printed wiring board for fixing and wiring the LED element 10. The heat radiating plate 12 is a member for radiating the heat generated from the LED element 10 and is made of a material having high thermal conductivity, for example, a metal material such as aluminum, copper, silver, or an alloy thereof, or aluminum nitride. Formed from a ceramic material.

The heat-dissipating columnar member 31 is also a member for dissipating heat generated from the LED element 10, and is a material having high thermal conductivity, for example, a metal material such as aluminum, copper, silver, or an alloy thereof. It is formed from a ceramic material such as aluminum nitride.

The optical sheet 6 is a member for suppressing the occurrence of large luminance unevenness and color unevenness by mixing light traveling at different angles and reorienting the angle at the same point in the plane.

As shown in FIG. 3C, a plurality of heat radiation columnar members 31 formed in a circular tube are fitted into the through holes provided in the LED substrate 11 and the heat radiation plate 12. Thereby, the heat generated from the LED element 10 and accumulated in the LED substrate 11 is transmitted to the heat radiating columnar member 31, and further, the heat is transmitted from the heat radiating columnar member 31 to the heat radiating plate 12. It is possible to suppress the heat from continuing to accumulate.

According to the liquid crystal display device according to the first embodiment, the heat accumulated in the LED substrate is sufficiently transmitted to the heat dissipation plate through the heat dissipation columnar member, and as a result, the heat generated from the LED element is efficiently dissipated, It is possible to suppress the deterioration of the life characteristics of the LED element and the decrease in light emission efficiency.

In the first embodiment, the heat radiating columnar member 31 is formed in a circular tube shape (eyelet shape, bush shape), but the shape of the heat radiating columnar member 31 is not limited thereto, and, for example, has no space inside. It may be formed in a core shape. Moreover, the cross section perpendicular | vertical with respect to the expansion | extension direction of the columnar member 31 for thermal radiation is not restricted circularly, A polygon and an indeterminate form may be sufficient.

Embodiment 2
In the first embodiment, the LED substrate, the heat radiating plate, and the screw for fixing the LED substrate fixing plate, and the heat radiating columnar member are attached to different locations, respectively, but in the second embodiment, a circular tube shape is used. The screw is attached through the formed heat radiation columnar member. The second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic plan view of the LED element included in the liquid crystal display device according to the second embodiment and its peripheral structure, and FIG. 5 is a schematic top view of the LED element included in the liquid crystal display device according to the second embodiment and its peripheral structure. FIG.

As shown in FIG. 4, the screw 14 is disposed in the hole of the heat dissipation columnar member 32 formed in a circular tube shape, and the LED substrate 11, the heat dissipation plate 12, and the LED substrate fixing plate 13 are fixed. According to this, since space can be saved rather than attaching the heat-dissipating columnar member 32 and the screw 14 to different locations on the LED substrate 11, the degree of freedom in designing the arrangement of the LED elements 10 can be increased. it can. Further, since the heat radiating columnar member 32 and the screw 14 are in contact with each other, heat can be efficiently transmitted from the heat radiating columnar member 32 to the LED substrate fixing plate 13 via the screw 14.

Also in the second embodiment, as shown in FIG. 5, the LED substrate 11 and the LED substrate 41 are arranged with a light guide plate (not shown) interposed therebetween, and the heat dissipation columnar member 32 and the LED substrate attached to the LED substrate 11. The LED element 10 attached to 41 is arranged to face each other. Further, the LED element 10 attached to the LED substrate 11 and the columnar member 32 for heat dissipation attached to the LED substrate 41 are arranged to face each other. Note that the two sets of screws 14 and the heat-dissipating columnar member 32 indicated by dotted lines in FIG. 5 indicate that at least one of the two sets may be attached.

Embodiment 3
In Embodiment 1, the heat dissipating columnar member and the LED substrate and the through hole provided in the heat dissipating plate were fitted, but in Embodiment 3, the heat dissipating columnar member was added to the LED substrate and the heat dissipating plate, Further, it is fitted into a through hole provided in the LED board fixing plate.

Hereinafter, the liquid crystal display device according to Embodiment 3 will be described in detail with reference to FIGS. 6 and 7. Descriptions of matters common to the other embodiments are omitted here. FIG. 6 is a schematic plan view of the LED element included in the liquid crystal display device according to the third embodiment and its peripheral structure. FIG. 7 is a schematic top view of the LED element included in the liquid crystal display device according to the third embodiment and its peripheral structure. FIG. In the third embodiment, as shown in FIG. 6, the columnar member 33 for heat dissipation formed in a circular core shape is fitted into the through holes provided in the LED substrate 11, the heat dissipation plate 12, and the LED substrate fixing plate 13. Is done.

Also in the third embodiment, as shown in FIG. 7, the LED substrate 11 and the LED substrate 41 are arranged with a light guide plate (not shown) interposed therebetween, and the heat dissipating columnar member 33 attached to the LED substrate 11 The LED element 10 attached to the LED substrate 41 is disposed to face the LED board 41. In addition, the LED element 10 attached to the LED substrate 11 and the columnar member 33 for heat dissipation attached to the LED substrate 41 are arranged to face each other.

According to the liquid crystal display device according to the third embodiment, the heat accumulated in the LED substrate 11 by the heat radiating columnar member 33 can be efficiently transmitted not only to the heat radiating plate 12 but also to the substrate fixing plate 13. The heat generated from 10 can be radiated more efficiently, and the deterioration of the life characteristics and the light emission efficiency of the LED element 10 can be further suppressed. Moreover, since the columnar member 33 for heat radiation also plays a role of fixing the LED substrate 11, the heat dissipation plate 12, and the substrate fixing plate 13, the screw 14 in the first embodiment is not necessary, and members and labor can be saved.

A modification of the heat radiating columnar members of the first to third embodiments will be described with reference to FIG. FIG. 8 is a schematic view according to a modification of the heat dissipating columnar members of the first to third embodiments.

As shown in FIG. 8, the shape of the heat dissipating columnar member 35 of the first to third embodiments may be a circular core having a taper. The heat dissipation plate 12 is detached from the heat dissipation columnar member 35 by inserting the heat dissipation columnar member 35 from the smaller circle diameter with respect to the LED substrate 11, the heat dissipation plate 12, and the LED substrate fixing plate 13. Can be prevented.

Embodiment 4
In Embodiment 3, the shape of the heat radiating columnar member is a circular core, but in Embodiment 4, the heat radiating columnar member is a circular tube having a flange at one end.

Hereinafter, the liquid crystal display device according to Embodiment 4 will be described in detail with reference to FIG. Descriptions of matters common to the other embodiments are omitted here. FIG. 9 is a schematic cross-sectional view of a heat dissipation columnar member provided in the liquid crystal display device according to the fourth embodiment. As shown in FIG. 9, the heat dissipation columnar member 34 of the fourth embodiment is a circular tube, and one end portion of the circular tube has a collar (hereinafter also referred to as a flange) 29. As shown in FIG. 9, the heat radiation columnar member 34 is inserted into and penetrates the LED substrate 11, the heat dissipation plate 12, and the LED substrate fixing plate 13 from the edge where the flange 29 is not attached. The LED substrate 11 is firmly supported by the flange 29 of the columnar member 34.

Embodiment 5
In the fourth embodiment, the heat radiation columnar member is a circular tube having a collar at one end portion. In the fifth embodiment, the heat radiation columnar member is further fitted into the through hole of the substrate fixing plate. The other end of the heat radiating columnar member is bent outward.

Hereinafter, the liquid crystal display device according to the fifth embodiment will be described in detail with reference to FIGS. 10 and 11. Descriptions of matters common to the other embodiments are omitted here. FIG. 10 is a schematic diagram showing a process of deforming the heat radiation columnar member of FIG. 9, and FIG. 11 is a cross-sectional schematic diagram showing the heat radiation columnar member of FIG. 9 deformed by the process of FIG.

As shown in FIG. 10, the heat dissipation columnar member 34 of the fifth embodiment is pressed into the through hole of the LED substrate 11, the heat dissipation plate 12, and the LED substrate fixing plate 13, and then the bending tool 50 is pressed. As shown in FIG. 11, the protrusion is plastically deformed and bent outward. Accordingly, the LED substrate 11 can be supported by the flange 29, and the LED substrate fixing plate 13 can be firmly supported by the portion bent by plastic deformation. Therefore, the LED substrate 11, the heat radiating plate 12, and the LED substrate fixing plate 13 can be more firmly fixed without falling off the heat radiating column member 34.

Embodiment 6
In the fifth embodiment, the other end portion of the heat radiating columnar member is bent outward after the heat radiating columnar member is fitted into the through hole of the substrate fixing plate. In the sixth embodiment, the end of the heat radiating columnar member is folded. Pressure is applied to the part to widen the diameter of the end part.

Hereinafter, the liquid crystal display device according to Embodiment 6 will be described in detail with reference to FIG. Descriptions of matters common to the other embodiments are omitted here. 12 is a schematic cross-sectional view showing the heat-dissipating columnar member of FIG. 9 modified by a process different from FIG.

As shown in FIG. 12, in the sixth embodiment, the through hole of the substrate fixing plate 13 is expanded in a dish shape as a premise. After the heat dissipation columnar member 34 of the sixth embodiment is inserted into the through holes of the LED substrate 11, the heat dissipation plate 12, and the LED substrate fixing plate 13, pressure is applied from the LED substrate fixing plate 13 side by a bending tool or the like. The columnar member 34 for heat dissipation is spread in a dish shape, so that it becomes an eyelet shape and the caulking strength is increased. As a result, the LED substrate 11, the heat radiating plate 12, and the substrate fixing plate 13 can be more firmly fixed by the heat radiating columnar member 34. Moreover, since the adhesion between the heat radiation columnar member 34 and the substrate fixing plate 13 is improved by applying pressure, heat conduction from the heat radiation columnar member 34 to the substrate fixing plate 13 can be performed more efficiently. .

Embodiment 7
In the fifth and sixth embodiments, the heat radiating columnar member is irreversibly plastically deformed. However, in the seventh embodiment, the end of the heat radiating columnar member is divided by slitting, and the heat radiating columnar member is reversible. It is elastically deformed.

Hereinafter, the liquid crystal display device according to the seventh embodiment will be described in detail with reference to FIGS. 13 and 14. Descriptions of matters common to the other embodiments are omitted here. FIG. 13 is a schematic top and side view of the heat dissipating columnar member provided in the liquid crystal display device according to the seventh embodiment. FIG. 14 is a schematic cross-sectional view illustrating a state in which the heat dissipating columnar member of FIG. .

As shown in FIG. 13, the columnar member 36 for heat radiation according to the seventh embodiment has a columnar structure in which a slit portion 37 is formed, and the end portions divided by the slit of the columnar structure each have a flange portion 38. And has a flange 39 at the other end of the columnar member 36 for heat dissipation. According to this, as shown in FIG. 14, the LED substrate 11 is supported by the collar 39 and the LED substrate fixing plate 13 is supported by the flange portion 38. Therefore, the LED substrate 11, the heat dissipation plate 12, and The LED board fixing plate 13 does not fall out of the heat radiating columnar member 36 and can be fixed more firmly. Furthermore, by providing the slit portion 37, it is possible to remove the heat-dissipating columnar member 36 once attached by elastic deformation.

The first to seventh embodiments may be appropriately combined.

The present application claims priority based on the Paris Convention or the laws and regulations of the country to which the transition is based on Japanese Patent Application No. 2010-235772 filed on October 20, 2010. The contents of the application are hereby incorporated by reference in their entirety.

1: liquid crystal display device 5: light guide plate 6: optical sheet 10: LED element 11, 41: LED substrate 12: heat sink 13: LED substrate fixing plate 14, 15: screw 16: support member 17: power connector 29: collar ( Flange)
30:

Liquid crystal panels

31, 32, 33, 34, 35, 36: Heat-dissipating columnar member 37: Slot 38: collar 39: collar 50: bending tool 110: LED light source 115: wiring board 121: circuit board 122: First radiator 123: second radiator 124: frame

Claims

A lighting device including a substrate to which a light emitting element is attached, a heat radiating plate, and a substrate fixing plate,
The substrate is attached to one surface of the heat sink,
The substrate fixing plate is attached to the opposite side of the surface of the heat sink to which the substrate is attached,
The lighting device includes a columnar member for heat dissipation fitted into a through hole provided in the substrate and the heat dissipation plate,
The lighting columnar member has a smooth surface in contact with the substrate and the heat dissipation plate.
The illumination device further includes a light guide plate,
A pair of the substrates are arranged with the light guide plate in between,
The heat dissipation columnar member of one substrate of the pair of substrates and the light emitting element of the other substrate are arranged to face each other, and the light emitting element of the one substrate and the heat dissipation columnar member of the other substrate are opposed to each other. The lighting device according to claim 1, wherein the lighting device is arranged.
The lighting device according to claim 1, wherein the heat dissipating columnar member is further fitted into a through-hole provided in the substrate fixing plate.
The lighting device according to claim 3, wherein the heat dissipating columnar member has a flange at one end portion.
5. The lighting device according to claim 4, wherein the heat radiating columnar member is a circular tube, and the other end portion of the heat radiating columnar member is bent outward after being fitted into the substrate fixing plate. .
5. The heat dissipating columnar member is a circular tube, and the other end of the heat dissipating columnar member is a member whose pressure is increased after being fitted into the substrate fixing plate and the diameter thereof is widened. The lighting device described.
The heat dissipating columnar member is a circular core having a slit formed on one end portion, and the circular core on the side on which the slit is formed has a flange, and the other end of the heat dissipating columnar member is The lighting device according to claim 3, wherein the portion has a collar.
A liquid crystal display device comprising a liquid crystal sealed between a pair of opposed substrates,
A liquid crystal display device comprising the illumination device according to any one of claims 1 to 7.