WO2010113362A1

WO2010113362A1 - Illuminating device, display device and television receiver

Info

Publication number: WO2010113362A1
Application number: PCT/JP2009/071214
Authority: WO
Inventors: 泰守黒水
Original assignee: シャープ株式会社
Priority date: 2009-03-31
Filing date: 2009-12-21
Publication date: 2010-10-07

Abstract

An illuminating device (12) is provided with a light source (17), a chassis (14) which houses the light source (17), and a grounding member (80) which grounds the light source (17). The grounding member (80) has a base material (81) and a grounding terminal (89) formed on the base material (81). The grounding terminal (89) is connected to the base material (81) and the chassis (14).

Description

Lighting device, display device, and television receiver

The present invention relates to a lighting device, a display device, and a television receiver.

For example, since a liquid crystal panel used in a liquid crystal display device such as a liquid crystal television does not emit light, a backlight device is separately required as a lighting device. The backlight device is installed on the back side (the side opposite to the display surface) of the liquid crystal panel, and includes a large number of lamps (for example, cold cathode tubes), a case for housing the lamps, and each lamp. A circuit board that controls turning on / off of the light is known (for example, Patent Document 1).

The apparatus disclosed in Patent Document 1 is provided with a metal frame having an opening on the lower surface side of a case, and an electronic component on a circuit board is disposed in the opening so that the electronic component is a metal frame. It is supposed that it is prevented from sticking to the surface and leakage is suppressed. Furthermore, the heat radiation effect with respect to the heat generation of the electronic components mounted on the circuit board is enhanced by bringing the frame into close contact with the lower surface of the case.

JP 2000-47208 A

(Problems to be solved by the invention)
By the way, in recent years, the brightness of the lamp has been increased, and particularly, the lamp itself tends to become high temperature as the gas pressure and current are increased. However, in the apparatus disclosed in Patent Document 1, it is difficult to effectively suppress the increase in temperature of the lamp because no heat dissipation measure is provided on the lamp side. Various electronic components on the circuit board close to the lamp are generally fixed to the circuit board by soldering. Accordingly, when the temperature of the lamp is increased, the temperature of the circuit board is also increased, and the solder portion of the circuit board is increased in temperature, so that thermal stress is generated and the solder portion may be damaged.

The present invention has been made based on the above situation, and an object of the present invention is to provide an illumination device that can efficiently dissipate heat generated from a light source. Another object of the present invention is to provide a display device provided with the illumination device and a television receiver provided with the display device.

(Means for solving the problem)
In order to solve the above-described problem, an illumination device of the present invention includes a light source, a chassis that houses the light source, and a grounding member for grounding the light source. A ground terminal formed on a base material, wherein the ground terminal is connected to the base material and the chassis.

According to such a configuration, the heat generated by the lighting of the light source is transmitted to the base member of the ground member and the chassis via the ground terminal. In general, although the ground terminal is formed on the base material to ground the light source, the base material has a small area and thus has a small heat dissipation capability, and the light source is easily heated. On the other hand, since the chassis accommodates the light source and has a large area, it is possible to dissipate heat over a wide range by connecting the ground terminal not only to the base material but also to the chassis. As a result, the heat generated from the light source can be efficiently dissipated, and the temperature of the light source can be suppressed from increasing.

The chassis may be made of metal.
As a result, heat transfer in the chassis is improved and a high heat dissipation effect can be obtained.

A circuit board on which electronic components are soldered may be disposed on the opposite side of the chassis from the light source.
As described above, when the electronic component is provided with a soldered circuit board, when the temperature of the light source is increased, the circuit board also rises in temperature, and the soldered portion is subjected to thermal stress. The part will be damaged. Therefore, by adopting the configuration of the present invention, it is possible to suppress the temperature rise of the circuit board and to make it difficult for thermal stress to be applied to the solder portion.

The ground terminal may be connected vertically to the chassis.
According to such a configuration, since the length of the ground terminal can be made as small as possible, efficient heat dissipation can be realized.

The grounding member may have a leg portion projecting toward the chassis, and the leg portion may be in contact with the chassis.
In this case, since the heat generated from the cold cathode tube is transmitted to the support plate and the chassis via the legs, it is possible to suppress the temperature of the cold cathode tube from increasing.

The lighting device of the present invention includes a light source including an electrode that enables electrical connection with the outside, a chassis that houses the light source, the light source, and is electrically connected to the electrode, A grounding member for grounding the light source, and the grounding member is connected to the chassis.
According to such a configuration, heat generated by lighting the light source is transmitted to the chassis via the ground member. Since the chassis accommodates the light source and has a large area, heat can be radiated over a wide range by connecting the grounding member to the chassis. As a result, the heat generated from the light source can be efficiently dissipated, and the temperature of the light source can be suppressed from increasing.

When the chassis is made of metal, heat transfer in the chassis is improved and a high heat dissipation effect can be obtained.

The chassis and the ground member may be connected by arc welding.
The chassis and the ground member may be connected by laser welding.
Alternatively, the chassis and the ground member can be connected by solder.
In this case, the chassis and the grounding member can be firmly connected, and high reliability can be obtained in the lighting device.

The lighting device of the present invention includes a light source, a chassis that houses the light source, a grounding member for grounding the light source, and a heat radiating plate that radiates heat from the light source separately from the chassis. And the grounding member is connected to the heat sink.
According to such a configuration, the heat generated by the lighting of the light source is transmitted to the heat radiating plate via the ground member. As a result, the heat generated from the light source can be efficiently radiated from the heat radiating plate, and the temperature rise of the light source can be suppressed.

The chassis can be made of resin.
By providing the heat radiating plate as described above, it is not necessary for the chassis to have a high heat radiating property, so that the chassis can be made of a resin that can be easily processed.

The heat sink can be made of metal.
As a result, heat transfer within the heat radiating plate is improved, and a high heat radiating effect can be obtained.

The said heat sink shall be distribute | arranged to the opposite side to the said light source with respect to the said chassis.
According to such a configuration, since the heat radiating plate is arranged on the outside (back side) of the chassis, the heat radiated from the heat radiating plate does not go into the chassis and can be radiated efficiently. Become.

The ground member may be connected perpendicularly to the heat sink.
According to such a configuration, the distance between the ground member and the heat radiating plate can be made as small as possible, so that efficient heat radiation can be realized.

The light source includes a glass tube and a base attached to an end of the glass tube so as to cover the outside of the glass tube, and the base is connected to the grounding member. be able to.
In this case, the heat generated from the light source is radiated from the base through the ground terminal to the ground member and the chassis.

Next, in order to solve the above-described problems, a display device of the present invention includes the above-described lighting device and a display panel that performs display using light from the lighting device.
According to such a display device, since the lighting device having excellent heat dissipation is provided, it is possible to provide a display device with high reliability and durability that hardly causes thermal fatigue due to the influence of high heat.

A liquid crystal panel can be exemplified as the display panel. Such a display device can be applied as a liquid crystal display device to various uses such as a display of a television or a personal computer, and is particularly suitable for a large screen.

Moreover, the television receiver of this invention is provided with the said display apparatus.
According to such a television receiver, it is possible to provide a device having excellent operation reliability and durability.

(The invention's effect)
According to the present invention, it is possible to provide a highly reliable lighting device by efficiently radiating heat generated from a light source.

1 is an exploded perspective view showing a schematic configuration of a television receiver according to Embodiment 1 of the present invention. Exploded perspective view showing schematic configuration of liquid crystal display device Sectional drawing which shows the structure of the AA line cross section of the liquid crystal display device of FIG. The top view which shows schematic structure of the backlight apparatus with which the liquid crystal display device of FIG. 2 is equipped. The perspective view which shows schematic structure of a relay connector Partial enlarged front view showing the connection structure between the relay connector and the cold cathode tube Side view showing schematic configuration of relay connector Explanatory drawing which shows the aspect by which the nozzle | cap | die of the cold cathode tube was inserted by the relay connector The perspective view which shows schematic structure of a cold cathode tube Side view showing the configuration of a base externally fitted to a cold cathode tube The perspective view which shows schematic structure of a grounding member The perspective view which shows the structure of the light source holding part with which a grounding member is equipped. Sectional view showing the cold cathode tube cap locked to the stopper Partial enlarged front view showing the connection configuration between the light source holding part and the cold cathode tube The perspective view which shows the structure of the back surface side of a grounding member The principal part expanded sectional view which shows the cross-sectional structure of the liquid crystal display device of the state which attached the cold cathode tube to the grounding member Sectional drawing which shows the modification of the connection aspect of a grounding member and a chassis. Sectional drawing showing a mode that the cold cathode tube was inserted by the grounding member in the backlight apparatus which concerns on Embodiment 2 of this invention. The principal part expanded sectional view which shows the cross-sectional structure of the liquid crystal display device of the state which attached the cold cathode tube to the grounding member of FIG. The principal part expanded sectional view which shows the cross-sectional structure of the state which attached the cold cathode tube to the grounding member in the liquid crystal display device which concerns on Embodiment 3 of this invention.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. In the present embodiment, a television receiver TV including the liquid crystal display device 10 is illustrated.
As shown in FIG. 1, the television receiver TV according to the present embodiment includes a liquid crystal display device 10 (display device), front and back cabinets Ca and Cb that are accommodated so as to sandwich the liquid crystal display device 10, and a power source P. And a tuner T. The liquid crystal display device 10 has a horizontally long rectangular shape as a whole, and includes a liquid crystal panel 11 as a display panel and a backlight device 12 (illumination device) as an external light source, as shown in FIG. It is integrally held by a bezel 13 or the like having a shape.

Next, the liquid crystal panel 11 and the backlight device 12 constituting the liquid crystal display device 10 will be described (see FIGS. 2 to 4).
The liquid crystal panel 11 is configured such that a pair of glass substrates are bonded together with a predetermined gap therebetween, and liquid crystal is sealed between the glass substrates. One glass substrate is provided with a switching element (for example, TFT) connected to a source wiring and a gate wiring orthogonal to each other, a pixel electrode connected to the switching element, and the other glass substrate is opposed to An electrode and a color filter in which colored portions such as R (red), G (green), and B (blue) are arranged in a predetermined arrangement are provided.

The backlight device (illumination device) 12 is a so-called direct-type backlight device, and a light source (here, a cold cathode tube) is provided directly below the back surface of the panel surface (ie, display surface) of the liquid crystal panel 11 along the panel surface. 17 is used).

The backlight device 12 includes a substantially box-shaped chassis 14 whose upper surface is open, and a plurality of optical members 15 (a diffusion plate, a diffusion sheet, and a lens sheet, which are attached in order from the lower side in the drawing). , A reflective polarizing plate) and a frame 16 for holding these optical members 15 on the chassis 14. Further, in the chassis 14, there are a cold cathode tube 17, a lamp clip 18 for attaching the cold cathode tube 17 to the chassis 14, a lamp holder 19 that holds an end of the cold cathode tube 17, and a group of cold cathode tubes 17. And the holder 20 that collectively covers the lamp holder 19 group. In the backlight device 12, the optical member 15 side is the light emitting side from the cold cathode tube 17.

The chassis 14 is made of metal such as aluminum, and is formed in a shallow, substantially box shape including a rectangular bottom plate 14a and side surfaces rising from the sides. As shown in FIG. 4, the chassis 14 accommodates a plurality of cold cathode tubes 17 arranged in parallel. Further, the chassis 14 is provided with a reflection sheet 14b on the side opposite to the light emission side of the cold cathode tube 17 (the inner surface side of the bottom plate 14a of the chassis 14), thereby forming a light reflection surface.

The reflection sheet 14b is made of synthetic resin, and the surface thereof is white with excellent light reflectivity. As shown in FIG. 4, the reflection sheet 14b is laid so as to cover almost the entire area along the inner surface of the chassis 14. The bottom surface of the chassis 14 is integrated. With this reflection sheet 14b, the light emitted from the cold cathode tube 17 can be reflected toward the optical member 15 such as a diffusion plate.

On the surface of the chassis 14 opposite to the side where the cold cathode tube 17 is attached (the outer surface and the back surface of the bottom plate 14a of the chassis 14), as shown in FIG. An inverter board (circuit board) 30 is attached to the left side end in FIG. That is, in the present embodiment, the cold cathode tube 17 is so-called one-side driven. The inverter board 30 is formed as a whole from a synthetic resin such as paper phenol, on which various electronic components are mounted. Specifically, a lead component 30a such as a transformer or a capacitor is mounted on the back surface (surface opposite to the chassis 14) of the inverter board 30, and on the front surface (surface on the chassis 14 side), A wiring pattern (not shown) is formed, and a chip component 30b such as a resistor, a diode, or a capacitor is mounted. Among these, the lead of the lead component 30 a is soldered to the wiring pattern in a state of protruding to the front side surface through the through hole of the inverter substrate 30. On the other hand, the chip component 30 b is surface-mounted on the wiring pattern on the surface on the front side of the inverter substrate 30.

When the inverter board 30 is assembled, a wall portion 42 of the relay connector 19 (described later) protruding to the back side of the chassis 14 and a board connection portion 53 disposed along the wall portion 42 are provided with the receiving electrode portion 31. Plugged into. As a result, power can be supplied from the inverter board 30 to the relay connector 19.

Next, the relay connector 19 will be described with reference to FIGS. The relay connector 19 is attached to the chassis 14 and connected to one end of the cold cathode tube 17.
FIG. 5 is a perspective view showing a schematic configuration of the relay connector, FIG. 6 is a partially enlarged front view showing a connection structure between the relay connector and the cold cathode tube, FIG. 7 is a side view showing the schematic configuration of the relay connector, and FIG. It is explanatory drawing which shows the aspect by which the nozzle | cap | die of the cathode tube was inserted by the relay connector.
As shown in FIG. 5, the relay connector 19 includes a holder 40 made of synthetic resin and a relay terminal 50 made of metal such as stainless steel housed in the holder 40. The holder 40 includes a box-shaped portion 41 having a block shape as a whole, and a wall portion 42 (see FIGS. 7 and 8) that protrudes from the back surface of the box-shaped portion 41 to the bottom side (the back surface side of the chassis 14). The

The box-shaped portion 41 is formed with a storage chamber 43 that opens from the front surface to the side surface (the side surface opposite to the side edge of the chassis 14). Among the openings of the storage chamber 43, the opening on the upper surface side (front side in FIG. 6, upper side in FIG. 7) is a receiving port for fitting an end portion (a base 70 described later) of the cold cathode tube 17 from the upper surface side. 44. On the other hand, the opening on the front side of the storage chamber 43 (the right side in FIG. 6, the front side in FIG. 7) is the cold cathode tube 17 in a state where the end (base 70) of the cold cathode tube 17 is stored in the storage chamber 43. An escape port 45 for avoiding interference with the glass tube 60 is used. The relief opening 45 is formed with a stopper 46 having an opening edge projecting inwardly in a plate shape, and the opening shape of the relief opening 45 is narrowed to a substantially U shape by the stopper 46. The opening width of the relief port 45 having a substantially U shape is smaller than the outer diameter of the main body 71 of the base 70 and the same as or slightly larger than the outer diameter of the glass tube 60 of the cold cathode tube 17. Has been. A rear end portion of the opening edge of the escape port 45 is a semicircular recess 47, and the radius of curvature of the recess 47 is the same as or slightly larger than the radius of curvature of the outer periphery of the glass tube 60. . Further, a portion of the opening edge of the escape port 45 on the front side of the recess 47 is a pair of guide portions 48.

The wall portion 42 is a plate-like member that can be inserted into the mounting hole 14h provided in the chassis 14, and a pair of retaining projections 49 are formed on the side surfaces (left and right sides in FIG. 7) of the wall portion 42. (See FIG. 7). The retaining protrusion 49 has a function of preventing the relay connector 19 from coming out of the chassis 14 when the relay connector 19 is inserted into the chassis 14.

On the other hand, the relay terminal 50 is held inside the holder 40. The relay terminal 50 is formed by bending a metal plate punched into a predetermined shape, and is formed by bending a pair of vertically symmetrical elastic pressing pieces 51 made of curved plate pieces and connecting the elastic pressing pieces 51 to each other at the bottom. The receiving part 52 (fitting receiving part) which makes | forms, and the connection part 53 for board | substrates which protrudes on a flat plate to the back side are provided.

The pair of elastic pressing pieces 51 are accommodated in the storage chamber 43 in a state where elastic bending in a direction away from each other is allowed, and the pair of elastic pressing pieces 51 in a free state where the elastic pressing pieces 51 are not elastically bent. The minimum distance between 51 is set to be smaller than the outer diameter of the main body 71 of the base 70 of the cold cathode tube 17.

The receiving portion 52 has a ring-like shape that surrounds a part of the peripheral surface of the base 70 provided in the cold cathode tube 17 and opens upward to allow the cold cathode tube 17 to be attached and detached (see FIG. 8). On the other hand, the board connection portion 53 is exposed from the back surface of the box-shaped portion 41 to the outside of the holder 40 and protrudes along the wall portion 42 to the bottom side (lower side in FIG. 7) of the holder 40.

When the relay connector 19 is assembled to the chassis 14, as shown in FIG. 8, the wall portion 42 of the holder 40 is inserted into the mounting hole 14 h from the inner surface side of the chassis 14, and the retaining projection 49 is formed on the rear surface of the chassis 14. It is locked to the opening edge of the mounting hole 14h. As a result, the holder 40 is fixed in a state in which movement in the assembly direction (through direction of the mounting hole 14 h) is restricted with respect to the chassis 14, and the relay connector 19 is assembled to the chassis 14. In this case, the wall portion 42 and the board connection portion 53 are projected to the rear side of the chassis 14.

Next, the cold cathode tube 17 connected to the relay connector 19 will be described with reference to FIGS.
FIG. 9 is a perspective view showing a schematic configuration of the cold cathode tube, and FIG. 10 is a side view showing a configuration of a base fitted on the cold cathode tube.

The cold cathode tubes 17 have an elongated tubular shape, and a large number of the cold cathode tubes 17 are accommodated in the chassis 14 in a state in which the length direction (axial direction) coincides with the long side direction of the chassis 14 (see FIG. 4). . As shown in FIG. 9, the cold cathode tube 17 includes an elongated glass tube 60 sealed at both ends, and an outer lead made of an elongated metal (for example, iron-nickel alloy) having a circular cross section protruding from both ends of the glass tube 60. 61 and a substantially cylindrical base (lead part) 70 disposed at both ends of the glass tube 60.
The inside of the glass tube 60 is filled with mercury or the like, and a phosphor is applied to the inner wall surface thereof. The parts covered by the caps 70 at both ends are set as non-light emitting parts, and other central parts are arranged. A part (that is, a part where the phosphor is applied) is a light emitting part.

The base 70 is a single part formed by bending or punching a metal (for example, stainless steel) plate material punched into a predetermined shape. The base 70 includes a main body 71 that is externally fitted to both ends of the glass tube 60, and a conductive piece 72 that extends from the end of the main body 71.

The main body 71 has a cylindrical shape concentric with the glass tube 60 as a whole, and the inner diameter of the main body 71 is slightly larger than the outer diameter of the glass tube 60. The main body 71 is formed such that three portions of the

elastic holding pieces

71a and 71b are arranged at a pitch of an equal angle (that is, 120 °) in the circumferential direction by cutting a part of the main body 71 into a slit shape. .

One of the pair of

elastic holding pieces

71a and 71b, the first elastic holding piece 71a as a whole extends in a cantilever shape in the axial direction (specifically, slightly inward in the radial direction). Thus, the base end can be elastically bent in the radial direction. The extended end portion of the first elastic holding piece 71a is bent obliquely outward in the radial direction, and a contact portion 74a where the outer surface of the bend (that is, the surface facing the inner side) contacts the outer peripheral surface of the glass tube 60 is provided. Have. A virtual circle connecting the contact portions 74a of the three pieces of the first elastic holding piece 71a is a concentric circle with the main body 71, and the diameter of the virtual circle is such that the first elastic holding piece 71a is elastically bent. When there is no free state, the dimension is smaller than the outer diameter of the glass tube 60.

On the other hand, of the pair of

elastic holding pieces

71a and 71b, the other second elastic holding piece 71b is disposed so as to be adjacent to the first elastic holding piece 71a in the circumferential direction. The second elastic holding piece 71b as a whole is extended in a cantilevered manner in a direction opposite to the first elastic holding piece 71a (specifically, slightly inwardly in the radial direction). The base end thereof can be elastically bent in the radial direction. The extended end portion of the second elastic holding piece 71b is a contact portion 74b that comes into contact with the outer peripheral surface of the glass tube 60, and the virtual circle connecting the contact portions 74b of the three pieces of second elastic holding piece 71b is The diameter of the virtual circle is smaller than the outer diameter of the glass tube 60 when the second elastic holding piece 71b is in a free state where it is not elastically bent.

A conductive piece 72 extending in a cantilever shape is formed on the front end edge of the main body 71. The conductive piece 72 includes an elongated portion 75 that continues to the front end portion of the main body portion 71, and a cylindrical portion 76 that protrudes further forward from the front end (extended end) of the elongated portion 75.

The elongated portion 75 is flush with the main body 71 and extends from the main body 71 in parallel to the axis thereof, and extends from the extended end of the base end 75a to the axis of the main body 71. An intermediate portion 75b extending radially inward, and a distal end portion 75c extending in parallel with the axis of the main body portion 71 from the extended end of the intermediate portion 75b. A cylinder is provided at the extended end of the distal end portion 75c. The continuous portions 76 are continuous. The width dimension of the elongated portion 75 is sufficiently smaller than the length dimension of the elongated portion 75, and accordingly, the elongated portion 75 is elastically deformed in the radial direction of the main body portion 71, the direction intersecting the radial direction (the elongated portion 75 Elastic deformation in the direction intersecting the length direction) and elastic torsional deformation around the elongated portion 75 itself are possible.

The cylindrical portion 76 is obtained by bending a portion projecting laterally from the extending end of the elongated portion 75 into a cylindrical shape, and the axis is disposed substantially coaxially with the main body portion 71. The tubular portion 76 can be displaced in the direction around the axis and the radial direction of the base 70 while elastically bending the elongated portion 75. The outer lead 61 of the cold cathode tube 17 is inserted into the cylindrical portion 76.

Next, an operation for attaching one end of the cold cathode tube 17 to the relay connector 19 will be described (see FIG. 8). At the time of attachment, the cold cathode tube 17 is made to approach the bottom plate 14 a of the chassis 14 in a horizontal state, and one end portion of the glass tube 60 and the base 70 are fitted into the accommodation chamber 43 of the relay connector 19. At this time, after one elastic pressing piece 51 is elastically bent so as to expand left and right by the main body portion 71 of the base 70, and after the main body portion 71 passes through the minimum interval portion of the pair of elastic pressing pieces 51, Both elastic

pressing pieces

51, 51 push the main body portion 71 into the inner side of the accommodation chamber 43 by the elastic restoring force and bring the main body portion 71 into contact with the receiving portion 52, thereby completing the mounting of the cold cathode tube 17. .

With the above attachment, the outer lead 61 is connected to the relay terminal 50 (receiving portion 52) through the base 70 so as to be electrically conductive. Further, the glass tube 60 is held in a state of being pressed against the concave portion 47 of the stopper 46 by the elastic restoring force of the pair of elastic pressing pieces 51, and when viewed in the axial direction of the cold cathode tube 17, It is located so that a part overlaps the stopper 46.

The attached cold cathode tube 17 is held by a pair of elastic pressing pieces 51 at both ends thereof, and is attached to the chassis 14 via the relay terminal 50 and the holder 40 which is an attachment base of the relay terminal 50.

Next, the ground member 80 to which the end of the cold cathode tube 17 opposite to the side connected to the relay connector 19 is connected will be described with reference to FIGS.
11 is a perspective view showing a schematic configuration of the grounding member, FIG. 12 is a perspective view showing a configuration of a light source holding portion provided in the grounding member, and FIG. 13 is a cross-sectional view showing a state in which the base of the cold cathode tube is locked by a stopper. 14 is a partially enlarged front view showing the connection structure between the light source holding part and the cold cathode tube, FIG. 15 is a perspective view showing the configuration of the back side of the ground member, and FIG. 16 is a state in which the cold cathode tube is attached to the ground member. It is sectional drawing which shows the cross-sectional structure of a liquid crystal display device.

As shown in FIG. 11, the grounding member 80 has an elongated support plate (base material) 81 and a plurality of light source holding portions 82 attached to the support plate 81. The grounding member 80 is disposed on the opposite side to the side on which the inverter board 30 is disposed in the long side direction of the chassis 14 (see FIG. 3).

The support plate 81 is made of a synthetic resin such as a glass epoxy resin. Three mounting holes 81h are formed through the support plate 81 at positions corresponding to the light source holding portions 82, and the leg portions 87 of the light source holding portion 82 are inserted into the mounting holes 81h. Is connected to the back side (the side opposite to the side where the cold cathode tube 17 is disposed).

As shown in FIGS. 12 to 14, the light source holding part 82 is obtained by bending a metal (for example, white alloy) plate material punched into a predetermined shape, and includes a base part 83 and a base part. A pair of vertically symmetrical elastic pressing pieces 84 extending from the upper and lower edges of 83 to the front side, and a stopper 85 extending from one side edge of the base 83 to the front side. The pair of elastic pressing pieces 84 are disposed on the side edge portion opposite to the stopper 85 and have a curved shape so as to swell toward the other side elastic pressing piece 84. The minimum distance between the pair of elastic pressing pieces 84 when the elastic pressing pieces 84 are not elastically bent is smaller than the outer diameter of the glass tube 60 of the cold cathode tube 17. The stopper 85 rises from the base portion 83 at a right angle to the axis of the cold cathode tube 17, and the stopper 85 is formed with a recess 86 that is recessed in a substantially arc shape.

Further, the base portion 83 is integrally formed with three leg portions 87. Of the three pieces, two pieces of leg portions 87 are between the elastic pressing piece 84 and the stopper 85, and are opposite to the elastic pressing piece 84 and the stopper 85 from the upper and lower edges of the base portion 83 (back side). The remaining one piece of the leg portion 87 is located on the opposite side of the elastic pressing piece 84 and the stopper 85 from the middle position of the two elastic pressing pieces 84 on the side edge of the base portion 83 opposite to the stopper 85 ( Projects to the back side.

The light source holding portion 82 is fixed to the support plate 81 by soldering with the leg portion 87 passing through the mounting hole 81h while being in a bare state (see FIG. 15). On the back surface side of the support plate 81, a ground pattern 88 extends with a uniform width so as to straddle the light source holding portions 82 arranged in parallel. Each light source holding portion 82 is electrically connected to the ground terminal 89 by the ground pattern 88.

As shown in FIG. 15, a ground terminal 89 is provided at one of the four corners of the rectangular ground pattern 88. The ground terminal 89 is a long and thin plate-like member made of metal, and is configured to rise substantially vertically with respect to the support plate 81 from the ground pattern 88.

Next, an operation of attaching the other end of the cold cathode tube 17 to the ground member 80 will be described (see FIG. 13). At the time of attachment, the cold cathode tube 17 is placed in a horizontal state so as to approach the bottom plate 14 a of the chassis 14, and one end portion of the glass tube 60 and the base 70 are fitted into the light source holding portion 82 of the ground member 80. At this time, after the pair of elastic pressing pieces 84 are elastically bent so as to expand left and right by the main body portion 71 of the base 70, and after the main body portion 71 passes through the minimum interval portion of the pair of elastic pressing pieces 84, Both elastic

pressing pieces

84, 84 hold the main body 71 by the elastic restoring force. Thus, the attachment of the cold cathode tube 17 is completed by bringing the main body portion 71 into contact with the base portion 83.

When the cold cathode tube 17 is attached to the ground member 80 as described above, the tip of the ground terminal 89 of the ground member 80 is connected to the ground pattern of the ground member 80 on the side where the ground member 80 is disposed, as shown in FIG. 88 and is in contact with the surface of the bottom plate 14a of the chassis 14 (the surface on the side where the cold cathode tubes 17 are disposed). More specifically, the ground terminal 89 rising substantially vertically from the support plate 81 is in contact with the bottom plate 14a perpendicularly and is fixed to the bottom plate 14a by soldering. As a result, the end of the cold cathode tube 17 can be grounded to the ground member 80 and the chassis 14 so that heat can be radiated to the ground member 80 and the chassis 14.

As described above, the backlight device 12 according to the present embodiment includes the cold cathode tube 17, the chassis 14 that houses the cold cathode tube 17, and the grounding member 80 for installing the cold cathode tube 17, The ground member 80 includes a support plate 81 and a ground terminal 89 formed on the support plate 81, and the ground terminal 89 is connected to the support plate 81 and the chassis 14.

According to such a configuration, heat generated by lighting the cold cathode tube 17 is transmitted to the support plate 81 and the chassis 14 via the ground terminal 89. In general, although the ground terminal 89 is formed on the support plate 81 of the ground member 80 to ground the cold cathode tube 17, the support plate 81 has a small area and thus has a small heat dissipation capability. The tube 17 is easily heated. Therefore, in the present embodiment, by connecting the ground terminal 89 not only to the support plate 81 but also to the chassis 14 having a large area, heat can be radiated over a wide range. As a result, the heat generated from the cold cathode tube 17 can be efficiently dissipated, and the high temperature of the cold cathode tube 17 can be suppressed.

Further, in the present embodiment, since the chassis 14 is made of metal, heat transfer within the chassis 14 is good, and a high heat dissipation effect can be obtained.

In the present embodiment, the inverter substrate 30 to which the lead component 30a and the chip component 30b are soldered is disposed on the opposite side of the chassis 14 from the cold cathode tube 17.
Thus, if it is set as the structure provided with the inverter board | substrate 30 with which various electronic components (the lead components 30a and the chip components 30b etc.) were soldered, when the cold cathode tube 17 becomes high temperature, a temperature rise will arise also in the inverter board | substrate 30. Thermal stress is applied to the soldered portion, and in some cases, the soldered portion is damaged. Thus, as in the present embodiment, the ground terminal 89 is connected to the support plate 81 and the chassis 14 so that the temperature rise of the inverter board 30 can be suppressed and the solder portion is hardly subjected to thermal stress. It becomes possible.

In the present embodiment, since the ground terminal 89 is connected perpendicularly to the chassis 14, the length of the ground terminal 89 can be made as small as possible, and efficient heat dissipation can be realized. It becomes.

In this embodiment, the cold cathode tube 17 includes a glass tube 60 and a base 70 attached to the end of the glass tube 60 so as to cover the outside of the glass tube 60, and the base 70 is a grounding member. 80.
In this case, heat generated from the cold cathode tube 17 is radiated from the base 70 through the ground terminal 89 to the ground member 80 and the chassis 14.

[Modification of Embodiment 1]
As a grounding mode between the grounding member 80 and the chassis 14 in the first embodiment, a mode as shown in FIG. 17 may be employed. That is, in the first embodiment, the grounding terminal 89 of the grounding member 80 is connected to the chassis 14. However, as shown in FIG. 17, the legs 87 protruding from the grounding member 80 toward the chassis 14 are provided on the support plate. It is good also as a structure which penetrates 81 and is connected with the chassis 14. FIG. In this case, the heat generated by the lighting of the cold cathode tube 17 is transmitted to the support plate 81 and the chassis 14 via the legs 87, and it is possible to suppress the temperature rise of the cold cathode tube 17.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the configuration of the grounding member is changed from the first embodiment, and the others are the same as in the first embodiment. The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.
18 is a cross-sectional view showing a state in which the cold cathode tube is fitted in the ground member in the backlight device according to the present embodiment, and FIG. 19 shows a cross-sectional configuration of the liquid crystal display device with the cold cathode tube attached to the ground member. It is a principal part expanded sectional view.

The grounding member 90 is obtained by bending a metal (for example, white alloy) plate material punched into a predetermined shape. As shown in FIG. A pair of vertically symmetrical elastic pressing pieces 84 extending from the edge part to the front side and a stopper 85 extending from one side edge part of the base part 83 to the front side are provided. The base portion 83 is integrally formed with three leg portions 91. Of the three pieces, two leg portions 91 are between the elastic pressing piece 84 and the stopper 85, and are opposite to the elastic pressing piece 84 and the stopper 85 from the upper and lower edges of the base portion 83 (back side). The remaining one leg portion 91 protrudes from the middle position between the two elastic pressing pieces 84 on the side edge of the base portion 83 opposite to the stopper 85 (on the side opposite to the elastic pressing piece 84 and the stopper 85). Projects to the back side.

The ground member 90 holds the cold cathode tube 17 by fitting the cold cathode tube 17 (base 70) between the pair of elastic pressing pieces 84, and the electrode (base 70) of the cold cathode tube 17. Electrically connected. As described above, the cold cathode tube 17 according to the present embodiment includes an electrode (a base 70) that enables electrical connection with the outside. Further, the ground member 90 is attached to the metal chassis 14. At the time of this attachment, as shown in FIG. 19, the grounding member 90 is arc-welded to the surface of the bottom plate 14a of the chassis 14 (the surface on the side where the cold cathode tubes 17 are disposed), thereby grounding the grounding member 90. 90 is fixed to the chassis 14. In the present embodiment, the ground member 90 is connected to the chassis 14 by arc welding, but may be connected by, for example, laser welding or soldering.

As described above, the backlight device 12 according to the present embodiment includes the cold cathode tube 17, the chassis 14 that houses the cold cathode tube 17, the cold cathode tube 17, and the electrodes of the cold cathode tube 17. And a grounding member 90 for grounding the cold cathode tube 17, and the grounding member 90 is connected to the chassis 14.

According to such a configuration, the heat generated by lighting the cold cathode tube 17 is transmitted to the chassis 14 via the ground member 90. The chassis 14 accommodates the cold cathode tube 17 and has a large area. Therefore, by connecting the ground member 90 to the chassis 14, heat can be radiated over a wide range. As a result, the heat generated from the cold cathode tube 17 can be radiated efficiently, and the temperature rise of the cold cathode tube 17 can be suppressed.

In the present embodiment, since the chassis 14 is made of metal, heat transfer in the chassis 14 is good, and a high heat dissipation effect can be obtained.

In the present embodiment, the chassis 14 and the ground member 90 are connected by arc welding.
In this case, the chassis 14 and the grounding member 90 can be firmly connected, and high reliability can be obtained in the lighting device.

<Embodiment 3>
Next, Embodiment 3 of the present invention will be described with reference to FIG. In the third embodiment, the configuration of the grounding member and the grounding mode are changed from those in the first and second embodiments, and the others are the same as those in the first and second embodiments. The same parts as those in the first and second embodiments are denoted by the same reference numerals and redundant description is omitted.
FIG. 20 is an enlarged cross-sectional view of a main part showing a cross-sectional configuration in a state where a cold cathode tube is attached to the ground member in the backlight device according to the present embodiment.

The chassis 14 is made of resin and is formed in a shallow, substantially box shape including a rectangular bottom plate 14a and side surfaces rising from the sides. As shown in FIG. 20, a cold cathode tube 17 is accommodated on the surface side of the chassis 14. On the other hand, a heat radiating plate 100 is attached to the rear surface of the chassis 14 (the surface opposite to the side where the cold cathode tubes 17 are arranged). The heat radiating plate 100 is a metal plate-like member, and is attached to the chassis 14 by a screw member 101. The heat radiating plate 100 has a function of radiating heat generated from the cold cathode tubes 17.

The ground member 110 is obtained by bending a metal (for example, white alloy) plate material punched into a predetermined shape, and a leg portion 111 extending from the base portion 83 toward the bottom plate 14a of the chassis 14 is integrally formed. Has been. The leg 111 penetrates through the bottom plate 14a of the chassis 14 and is connected to the heat sink 100 attached to the back surface of the bottom plate 14a. More specifically, the leg portion 111 extending substantially vertically from the base portion 83 is in contact with the heat radiating plate 100 vertically, and is fixed to the heat radiating plate 100 by soldering.

As described above, the backlight device 12 according to the present embodiment includes the cold cathode tube 17, the chassis 14 that houses the cold cathode tube 17, the grounding member 110 for grounding the cold cathode tube 17, and the chassis 14. And a heat radiating plate 100 for radiating heat from the cold-cathode tube 17, and a grounding member 110 is connected to the heat radiating plate 100.
According to such a configuration, the heat generated by lighting the cold cathode tube 17 is transmitted to the heat radiating plate 100 via the ground member 110. As a result, the heat generated from the cold cathode tube 17 can be efficiently radiated from the heat radiating plate 100, and the high temperature of the cold cathode tube 17 can be suppressed.

Further, in the present embodiment, since the heat radiating plate 100 is made of metal, heat transfer within the heat radiating plate 100 is good, and a high heat radiating effect can be obtained.

Further, in the present embodiment, the heat sink 100 is disposed on the opposite side of the cold cathode tube 17 with respect to the chassis 14.

In the present embodiment, the chassis 14 is made of resin. By providing the heat radiating plate 100 as in the present embodiment, the chassis 14 does not need to have a high heat radiating property, so that the chassis 14 can be made of a resin that can be easily processed.
In this case, since the heat radiating plate 100 is disposed on the outer side (back side) of the chassis 14, the heat radiated from the heat radiating plate 100 does not go into the chassis 14 and can be radiated efficiently. .

In the present embodiment, the ground member 110 is connected to the heat sink 100 perpendicularly.
According to such a configuration, since the distance between the ground member 110 and the heat radiating plate 100 can be made as small as possible, efficient heat dissipation can be realized.

<Other embodiments>
As mentioned above, although embodiment of this invention was shown, this invention is not limited to embodiment described with the said description and drawing, For example, the following embodiment is also contained in the technical scope of this invention.

(1) In Embodiment 1 described above, the ground terminal is connected to the bottom plate of the chassis. However, the connection location of the ground terminal is not limited to this, and may be connected to a part of the chassis.

(2) In the first embodiment described above, the configuration in which one grounding terminal is provided for one grounding member has been exemplified, but any number of grounding terminals can be provided. By increasing the number of ground terminals, more efficient heat dissipation can be expected.

(3) In each of the above-described embodiments, the configuration in which heat is radiated from the base provided in the cold cathode tube through the ground terminal is exemplified. For example, the outer lead protruding from the cold cathode tube is electrically connected to the ground terminal to radiate heat. The configuration is also included in the present invention.

(4) In each embodiment described above, a cold cathode tube is used as a light source. However, the light source is not limited to this, and a hot cathode tube, a xenon tube, a fluorescent lamp, or the like may be used.

(5) The display device is not limited to a liquid crystal display device, and includes various display devices that require a lighting device on the back side of the display panel.

DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display device (display device), 11 ... Liquid crystal panel (display panel), 12 ... Backlight device (illumination device), 14 ... Chassis, 17 ... Cold cathode tube (light source), 30 ... Inverter board (circuit board) , 30a ... Lead component (electronic component), 30b ... Chip component (electronic component), 60 ... Glass tube, 70 ... Base, 80 ... Ground member, 81 ... Support plate (base material), 89 ... Ground terminal

Claims

A light source;
A chassis that houses the light source;
A grounding member for grounding the light source,
The ground member has a base material and a ground terminal formed on the base material,
The grounding terminal is connected to the substrate and the chassis.
The lighting device according to claim 1, wherein the chassis is made of metal.
3. The lighting device according to claim 1, wherein a circuit board on which electronic components are soldered is disposed on the opposite side of the chassis from the light source.
The lighting device according to any one of claims 1 to 3, wherein the ground terminal is connected perpendicularly to the chassis.
The grounding member has a leg that protrudes toward the chassis,
The lighting device according to claim 1, wherein the leg is in contact with the chassis.
A light source with electrodes that allow electrical connection to the outside;
A chassis that houses the light source;
A grounding member for holding the light source, electrically connected to the electrode, and grounding the light source,
The lighting device, wherein the ground member is connected to the chassis.
The lighting device according to claim 6, wherein the chassis is made of metal.
The lighting device according to claim 6 or 7, wherein the chassis and the ground member are connected by arc welding.
The lighting device according to claim 6 or 7, wherein the chassis and the ground member are connected by laser welding.
The lighting device according to claim 6 or 7, wherein the chassis and the ground member are connected by solder.
A light source;
A chassis that houses the light source;
A grounding member for grounding the light source;
Separately from the chassis, a heat radiating plate for radiating heat from the light source,
The said grounding member is connected to the said heat sink, The illuminating device characterized by the above-mentioned.
The lighting device according to claim 11, wherein the heat radiating plate is made of metal.
The lighting device according to claim 11 or 12, wherein the heat radiating plate is disposed on a side opposite to the light source with respect to the chassis.
The lighting device according to any one of claims 11 to 13, wherein the chassis is made of resin.
The lighting device according to any one of claims 11 to 14, wherein the grounding member is connected perpendicularly to the heat radiating plate.
The light source includes a glass tube, and a base attached to an end of the glass tube so as to cover the outside of the glass tube,
The lighting device according to claim 1, wherein the base is connected to the ground member.
A display device comprising: the illumination device according to any one of claims 1 to 16; and a display panel disposed on a light emission side of the illumination device.
The display device according to claim 17, wherein the display panel is a liquid crystal panel using liquid crystal.
A television receiver comprising the display device according to claim 17 or 18.