JP2005234436A - Fixture and liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixture by which heat radiation efficiency of heat generated when a light source emits light is further enhanced and to provide a liquid crystal display. <P>SOLUTION: The fixture 2 consists of a metal member 7 fixed to a side surface 1a of a liquid crystal display unit 1 and a heat radiation member 9 intervening between the metal member 7 and the side surface 1a of the liquid crystal display unit 1 and having thermal conductivity higher than that of the metal member 7. The heat radiation member 9 has a contact part 9a coming into contact with the side surface 1a of the liquid crystal display unit 1 and a heat radiation part 9b provided extended from the contact part 9a so as not to be superposed on the side surface 1a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes an attachment having a function for attaching the liquid crystal display unit to the casing, and a function for releasing the heat of the light source provided in the liquid crystal display unit into the air or the casing, and the same. The present invention relates to a liquid crystal display device.

  Conventionally, as a liquid crystal display device, a light source such as a fluorescent lamp is arranged on the light incident end face of the light guide plate, and the light from the light source is guided to the back side of the liquid crystal panel using this light guide plate to illuminate the liquid crystal panel. An edge light type backlight type liquid crystal display device is known.

  The light source also generates heat during light emission (especially when a fluorescent lamp is used as the light source, the amount of heat generated at the electrode portions at both ends of the fluorescent lamp is large), and unevenness in brightness may occur in the liquid crystal panel due to the heat. is there. In addition, if the light source is not sufficiently dissipated and the temperature becomes high, the light emission efficiency from the light source decreases and the brightness of the liquid crystal panel decreases.

Therefore, conventionally, a heat radiating plate made of aluminum is provided on the back surface of the liquid crystal display unit, or in Patent Document 1 below, a heat radiating member made of copper foil is provided so as to cover the electrode portion of the fluorescent lamp, and heat generated by the fluorescent lamp. Is radiated to the outside through the heat radiating member.
Japanese Patent Laid-Open No. 10-106329

  However, in recent years, in order to increase the brightness of liquid crystal panels, two or more fluorescent lamps have been used as light sources, and the amount of heat generated from fluorescent lamps has increased as the number of fluorescent lamps has increased. ing. If so, there are limits to the conventional heat dissipation measures, and more effective heat dissipation measures are required.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a liquid crystal display device in which heat radiation efficiency of heat generated when a light source emits light is further improved.

  The fixture of the present invention is a metal member fixed to the side surface of the liquid crystal display unit, and is interposed between the metal member and the side surface of the liquid crystal display unit, and has a thermal conductivity larger than the thermal conductivity of the metal member. The heat dissipation member has a contact portion that is in contact with the side surface of the liquid crystal display unit and a heat dissipation portion that is extended from the contact portion so as not to overlap the side surface of the liquid crystal display unit. It is characterized by.

  The liquid crystal display device of the present invention includes a liquid crystal display unit and a fixture attached to a side surface of the liquid crystal display unit. The fixture is a metal member fixed to the side surface of the liquid crystal display unit, and the metal member. And a heat dissipating member having a thermal conductivity larger than that of the metal member, the heat dissipating member being in contact with the side surface of the liquid crystal display unit, And a heat dissipating part extended from the contact part so as not to overlap the side surface of the liquid crystal display unit.

  The heat from the light source is transmitted to the contact portion of the heat dissipation member that is in contact with the side surface through the side surface of the liquid crystal display unit, and is further dissipated into the air inside the housing from the heat dissipation portion that is not superimposed on the side surface. This is radiated to the outside space of the housing through the housing or exhausted from the vent to the outside of the housing by forced convection such as a fan. Alternatively, when the heat dissipating part is in contact with the housing, heat is transferred directly from the heat dissipating part to the housing and radiated to a space outside the housing. As described above, an excessive increase in the temperature of the light source and the liquid crystal display unit is suppressed by utilizing a phenomenon in which heat moves from the high temperature portion to the low temperature portion. The heat dissipating part provided in the heat dissipating member is not overlapped with the side surface of the liquid crystal display unit, that is, in the air inside the housing or in contact with the housing, which is a lower temperature part than the light source or the liquid crystal display unit. Therefore, the heat transmitted from the contact portion can be efficiently released from the heat radiating portion to the air inside the housing or the housing, which is a lower temperature portion.

  The metal member that is fixed to the side surface of the liquid crystal display unit with the heat dissipation member interposed has a function that is conventionally required for the fixture, that is, a function for fixing the liquid crystal display unit to the housing. . Moreover, the role which escapes the heat | fever transmitted through the contact part of the said heat radiating member which is contacting the metal member in the air inside a housing | casing or a housing | casing is also played.

  Further, if the heat dissipating part is bent from the contact part to the back side of the liquid crystal display unit, the heat dissipating part is positioned so as to overlap the back surface of the liquid crystal display unit. Does not invite an increase. Therefore, since the heat radiation portion can be expanded with a relatively large area without worrying about an increase in the planar size of the liquid crystal display device, the heat radiation area can be increased and the heat radiation efficiency can be improved accordingly.

  Furthermore, if the heat radiating part is brought into contact with the back surface of the liquid crystal display unit, the heat from the liquid crystal display unit can be directly transferred to the heat radiating part, the cooling efficiency of the liquid crystal display unit can be improved, and uneven brightness caused by heat. It is possible to suppress degradation of image quality such as.

  Further, if the metal member and the heat radiating member described above are integrated with each other, air in the heat conduction path between them can be eliminated, and the heat conduction efficiency from the heat radiating member to the metal member can be improved. It is possible to increase the contribution of the metal member to the heat dissipation and further improve the heat dissipation efficiency in combination with the heat dissipation member.

  According to the fixture of the present invention, the heat from the light source provided in the liquid crystal display unit can be released via the heat radiating member in contact with the side surface of the liquid crystal display unit, and the cooling efficiency of the liquid crystal display unit is increased. be able to.

  According to the liquid crystal display device of the present invention, the heat from the light source provided in the liquid crystal display unit can be released through the heat radiating member in contact with the side surface of the liquid crystal display unit, and the cooling efficiency of the liquid crystal display unit is improved. Can be increased. As a result, the brightness of the display surface can be improved, brightness unevenness can be prevented, and thermal deformation or failure of the parts can also be prevented. As a result, image quality and reliability can be improved.

  FIG. 1 is a schematic plan view of the liquid crystal display device according to the present embodiment. The liquid crystal display device includes a liquid crystal display unit 1 having a square display screen and a pair of attachments 2 attached to the left and right side surfaces 1a and 1b of the liquid crystal display unit 1, respectively.

  A schematic cross-sectional view of the liquid crystal display unit 1 is shown in FIG. The liquid crystal display unit 1 includes a liquid crystal panel 10, a light guide plate 21 disposed on the back surface (opposite surface of the display surface) of the liquid crystal panel 10, and a prism sheet 23 b disposed between the liquid crystal panel 10 and the light guide plate 21. An optical sheet such as a diffusion sheet 23 a, a reflection sheet 20 disposed on the back surface of the light guide plate 21, a light source 5 disposed opposite to the light incident end surface 21 a of the light guide plate 21, and a light source 5 are provided. Reflector 22.

  FIG. 12 is an exploded perspective view of the liquid crystal display device. The liquid crystal panel 10 encloses a liquid crystal material in two glass substrates 35, 36, forms a color filter on the upper (display screen side) glass substrate 35, and the lower (light guide plate 21 side) glass substrate 36. Is formed with thin film transistors, and polarizing plates 34a and 34b each having a function of passing light in one direction and blocking light in other directions by absorption, reflection or scattering are disposed outside the upper and lower glass substrates 35 and 36, respectively. Configured.

  In addition, the liquid crystal display device further includes a circuit board 38 on which a driving integrated circuit (driver IC) 39 for driving the liquid crystal panel 10 and a controller (control integrated circuit) for controlling them are mounted.

  As shown in FIG. 9, the light guide plate 21 is made of a transparent resin material having reflective dots 21b formed on the surface. One end face of the light guide plate 21 is a light incident end face 21a that receives light from the light source 5, and the light source 5 is disposed so as to face the light incident end face 21a.

  The light source 5 is, for example, a cold cathode fluorescent lamp that extends in a direction along the lower end surface of the liquid crystal panel 10 as shown in FIG. The electrode portions 5a and 5b at both ends of the light source 5 are connected to a driver 37 for driving the light source 5, as shown in FIG. The light source is not limited to a cold cathode fluorescent lamp, and a hot cathode fluorescent lamp, a light emitting diode, an EL (Electro Luminescence) element, or the like can be used.

  Next, the fixture 2 will be described. The fixture 2 includes a metal member 7 and a heat radiating member 9. The metal member 7 is attached to the side surface 1a (1b) of the liquid crystal display unit 1 and extends along the side surface 1a (1b) to one end portion of the band plate portion 7a. It consists of a substantially square mounting portion 7b. When the metal member 7 is attached to the side surface 1a (1b) of the liquid crystal display unit 1, the band plate portion 7a is parallel to the side surface 1a (1b), whereas the attachment portion 7b is parallel to the display screen of the liquid crystal panel 10. It is said. The attachment portion 7b is provided at a position extending from the strip plate portion 7a. Since the metal member 7 fixes the liquid crystal display unit 1 with respect to the housing, mechanical strength is required to stably support the liquid crystal display unit 1 on the housing even when an external impact is applied. Therefore, it consists of stainless steel, iron, magnesium, etc. excellent in mechanical strength.

  Further, as shown in FIG. 4, two through holes 13 a and 13 b and two screw holes 14 a and 14 b are formed in the band plate portion 7 a. The through holes 13a and 13b and the screw holes 14a and 14b are formed at substantially equal intervals along the longitudinal direction of the band plate portion 7a. The through holes 13a and 13b are located on both ends in the longitudinal direction of the band plate portion 7a, and screw holes 14a and 14b are located between the through holes 13a and 13b.

  Next, the heat radiating member 9 will be described. The heat dissipating member 9 is in contact with the side surface 1a (1b) of the liquid crystal display unit 1 and is bent substantially at right angles to the contact portion 9a, and does not overlap the side surface 1a (1b) of the liquid crystal display unit 1. Thus, the heat dissipating part 9b is provided so as to be extended from the contact part 9a. The cross-sectional shape of the heat dissipating member 9 is L-shaped as shown in FIG. The contact portion 9a and the heat radiating portion 9b both have a strip shape with the same length, and the width of the heat radiating portion 9b is larger. The heat radiating member 9 is formed into an L shape by, for example, bending. Alternatively, the contact portion 9a and the heat radiating portion 9b may be joined separately, but the mechanical strength can be increased by integrating them by bending as described above.

  When the heat dissipating member 9 is attached to the side surface 1a (1b) of the liquid crystal display unit 1, the contact portion 9a is contacted along the side surface 1a (1b), whereas the heat dissipating portion 9b is connected to the rear surface (display) of the liquid crystal display unit 1. Facing the other side of the surface). Unlike the metal member 7, the main function of the heat dissipating member 9 is heat dissipation that releases heat from the light source 5 and the liquid crystal display unit 1 to the air in the housing or the housing. Is also made of a material with high thermal conductivity. For example, it is made of aluminum. Alternatively, copper may be used. Or not only a single metal but an aluminum alloy and a copper alloy may be sufficient.

  Further, as shown in FIG. 4, four through holes 12 a to 12 d are formed in the contact portion 9 a of the heat radiating member 9. These through holes 12a to 12d are formed at substantially equal intervals along the longitudinal direction of the contact portion 9a.

  Next, attachment of the heat dissipation member 9 and the metal member 7 to the liquid crystal display unit 1 will be described.

  The metal member 7 and the heat radiating member 9 are integrated in advance before being attached to the liquid crystal display unit 1. As shown in FIG. 4, after the contact portion 9a of the heat radiating member 9 and the strip plate portion 7a of the metal member 7 are overlapped (through holes 13a and screw holes 14a formed in the strip plate portion 7a, The screw hole 14b and the through hole 13b are respectively matched with the through holes 12a, 12b, 12c and 12d formed in the contact portion 9a), and the through holes 12b and 12c formed in the contact portion 9a of the heat radiating member 9, respectively. The screws 16 are passed, and the screws 16 are screwed into the screw holes 14 a and 14 b formed in the band plate portion 7 a of the metal member 7. Thereby, the metal member 7 and the heat radiating member 9 are mutually fixed, and are made into one piece. Since the heat dissipating member 9 has an L shape, the mechanical strength of the metal member 7, which is mostly composed of the flat plate-like band plate portion 7 a, can be increased by integrating the metal member 7 and the heat dissipating member 9. That is, the mechanical strength of the fixture 2 composed of both of them increases due to the synergistic effect of the heat dissipation member 9 and the metal member 7.

  In addition, a screw hole may be formed in the contact part 9a of the heat radiating member 9, and the screw 16 may be screwed into the contact part 9a of the heat radiating member 9 from the band plate part 7a side of the metal member 7. However, when the heat dissipating member 9 is made of aluminum in order to give high heat dissipation, the formation of a screw hole with high accuracy in relatively soft aluminum in the metal can be made, for example, in stainless steel as the material of the metal member 7. Since it is difficult to compare, it is preferable that there is no step of forming screw holes in the heat dissipation member 9 made of aluminum.

  The metal member 7 and the heat radiating member 9 that are integrated as described above are attached to the side surface 1 a of the liquid crystal display unit 1 by screws 15. The screw 15 includes a through hole 13a of the band plate portion 7a of the metal member 7, a through hole 12a of the contact portion 9a of the heat radiation member 9 matched therewith, and a through hole 13b of the band plate portion 7a and a contact portion matched thereto. It penetrates through the through hole 12d of 9a and is screwed into a screw hole (not shown) formed in the side surface 1a of the liquid crystal display unit 1.

  Thereby, as shown in FIG. 3, the heat radiating member 9 has its contact portion 9a in contact with the side surface 1a of the liquid crystal display unit 1 and is fixed to the side surface 1a. The heat radiating part 9 b of the heat radiating member 9 is bent toward the back side of the liquid crystal display unit 1 and is in contact with the back side of the liquid crystal display unit 1.

  The metal member 7 is fixed to the side surface such that the contact portion 9a of the heat dissipation member 9 is sandwiched between the band plate portion 7a and the side surface 1a of the liquid crystal display unit 1.

  As shown in FIG. 10, the head of the screw 16 in which the metal member 7 and the heat radiating member 9 are integrated enters the concave portion 24 formed in the contact portion 9a of the heat radiating member 9, and enters the contact portion 9a. Since it does not protrude from the surface, good contact between the contact portion 9a of the heat dissipation member 9 and the side surface 1a of the liquid crystal display unit 1 can be obtained, and the contact portion 9a of the heat dissipation member 9 can be efficiently performed from the side surface 1a of the liquid crystal display unit 1. Can transmit heat.

  In the above attachment, since the metal member 7 and the heat radiating member 9 are integrated in advance, the attachment to the liquid crystal display unit 1 can be performed more easily than handling separately. Also, parts management becomes easy.

  Similarly, the heat radiating member 9 and the metal member 7 are attached to the other side surface 1b (not shown in FIGS. 3 and 4).

  And the attachment part 7b of each metal member 7 attached to the left and right side surfaces 1a and 1b extends from the side surfaces 1a and 1b as shown in FIG. 1, and the attachment part 7b is screwed to the housing. Thus, the liquid crystal display unit 1 is fixed to the casing.

  Next, the operation of the liquid crystal display device 1 will be described. When power is supplied to the light source 5, light is emitted from the light source 5. The light emitted from the light source 5 is collected by the reflector 22 shown in FIG. 9 or directly enters the light incident end face 21 a of the light guide plate 21. The light is uniformly reflected toward the liquid crystal panel 10 by the reflective dots 21 b formed on the light guide plate 21 or the reflection sheet 20 disposed on the back surface of the light guide plate 21. The direction of light emitted from the light guide plate 21 is changed by the diffusion sheet 23a and the prism sheet 23b so that the light enters the liquid crystal panel 10 substantially perpendicularly.

  The light emitted from the light source 5 is accompanied by heat generation, and in particular, the amount of heat generated at the electrode portions 5a and 5b at both ends is increased. In the present embodiment, the heat generated by the light source 5 can be released to a lower temperature portion through the heat radiating member 9. That is, the heat generated from the light source 5 is first transmitted to the metal reflector 22, and the heat is transmitted to the metal bezel 3 (shown in FIGS. 1 and 4) formed around the liquid crystal display unit 1. 3 is transmitted to the contact portion 9a of the heat dissipating member 9 that is in contact with the side surface of the heat dissipating member 3, and further transmitted from the contact portion 9a to the heat dissipating portion 9b.

  As a result, an excessive temperature rise of the liquid crystal display unit 1 (especially an excessive temperature rise near the light source 5 as a heating element) can be prevented, so that the brightness of the display screen can be improved and uneven brightness can be prevented. Generation of wrinkles due to thermal expansion of the optical sheet such as the sheet 23b can be prevented, and further, deterioration of characteristics due to high heat of the polarizing plate can be prevented. As described above, it is possible to prevent image quality deterioration and malfunction or failure of each component.

  Furthermore, since the heat radiating part 9b is in contact with the back surface of the liquid crystal display unit 1, heat from the liquid crystal display unit 1 can be directly transmitted to the heat radiating part 9b, and the cooling efficiency of the liquid crystal display unit 1 can be further improved. .

  In addition, since the metal member 7 and the heat radiating member 9 are integrally fixed to each other by the screwing described above, the heat conduction efficiency from the heat radiating member 9 to the metal member 7 can be increased, and the heat radiation can be reduced. The contribution of the metal member 7 can be increased, and the heat dissipation efficiency can be further improved in combination with the heat dissipation member 9.

  The mechanical strength for stably fixing the liquid crystal display unit 1 to the housing can be secured by the metal member 7 made of stainless steel. The heat dissipating member 9 is not attached to the housing, and is merely sandwiched between the side surface of the liquid crystal display unit 1 and the metal member 7, so that the dimensional accuracy is not so high.

  In addition, since heat is transmitted to the metal member 7 from the heat radiating member 9 in contact therewith, the metal member 7 also contributes to cooling of the light source 5 and the liquid crystal display unit 1. On the contrary, the heat radiating member 9 not only has a function of radiating heat but also supplements the mechanical strength of the metal member 7 by combining with the metal member 7, and as a result, contributes to improving the mechanical strength of the fixture 2. .

  As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to this, A various deformation | transformation is possible based on the technical idea of this invention.

  FIG. 5 shows a fixture according to a first modification. The heat dissipating member 19 in this fixture has a heat dissipating part 19b bent with respect to the contact part 19a in contact with the side surface 1a (1b) of the liquid crystal display unit 1, and the back surface of the liquid crystal display unit 1 contrary to the above embodiment. It is bent in the opposite direction.

  FIG. 6 shows a fixture according to a second modification. The heat dissipating member 17 in this fixture is parallel to the contact portion 17a so that the contact portion 17a is in contact with the side surface 1a (1b) of the liquid crystal display unit 1 and the contact plate 17a is sandwiched between the contact portion 17a. And a portion 17b for connecting the contact portion 17a and the portion 17c to increase the surface area contributing to heat dissipation.

  FIG. 7 shows a fixture according to a third modification. In the heat radiating member 26 in this fixture, the contact part 26a that is in contact with the side surface 1a (1b) of the liquid crystal display unit 1 extends in the thickness direction of the liquid crystal display unit 1 and protrudes from the liquid crystal display unit 1. Heat dissipating portions 26a and 26b that do not overlap the side surface 1a (1b) are provided.

  FIG. 8 shows a fixture according to a fourth modification. The metal member 7 and the heat radiating member 9 in this fixture are not integrated with each other by screwing, but are integrated with a bonding material (such as an adhesive or a metal material for welding) 18. Alternatively, it may be fixed by caulking.

  FIG. 11 shows a fixture according to a fifth modification. The heat radiating member 30 in this fixture includes a contact portion 31 that is in contact with the side surface of the liquid crystal display unit 1 and a heat radiating portion 32 that is bent from the contact portion 31 to the back side of the liquid crystal display unit 1. A fin 32 a is provided on the opposite surface of the heat dissipating portion 32 opposite to the back surface of the liquid crystal display unit 1. The fins 32a increase the surface area of the heat radiating part 32 and further increase the heat radiation efficiency.

  The light source 5 may be disposed on the upper end side of the liquid crystal display unit 1 in FIG. Further, the number is not limited to one and may be two or more.

It is a top view of the liquid crystal display unit and fixture which comprise the liquid crystal display device which concerns on embodiment of this invention. It is a perspective view of the fixture concerning the embodiment. It is sectional drawing of the state in which the fixture which concerns on the embodiment was attached to the liquid crystal display unit side surface. It is an expansion perspective view of the principal part in FIG. It is sectional drawing of the state by which the fixture by the 1st modification was attached to the liquid crystal display unit side surface. It is sectional drawing of the state by which the fixture by the 2nd modification was attached to the liquid crystal display unit side surface. It is sectional drawing of the state by which the fixture by the 3rd modification was attached to the liquid crystal display unit side surface. It is sectional drawing of the state by which the fixture by the 4th modification was attached to the liquid crystal display unit side surface. 1 is a schematic cross-sectional view of a liquid crystal display device according to an embodiment of the present invention. It is sectional drawing of the screwing location of the metal member and heat radiating member which concern on embodiment of this invention. It is a perspective view of the fixture by the 5th modification. 1 is an exploded perspective view of a liquid crystal display device according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display unit, 1a, 1b ... Side surface, 2 ... Mounting tool, 3 ... Bezel, 5 ... Light source, 5a, 5b ... Electrode, 7 ... Metal member, 7a ... Band plate part, 7b ... Mounting part, 9 ... Heat dissipation 9a ... contact part, 9b ... heat radiation part, 10 ... liquid crystal panel, 17 ... heat radiation member, 17a ... contact part, 17b, 17c ... heat radiation part, 18 ... joining material, 21 ... light guide plate, 26 ... heat radiation member, 26a ... contact part, 26b ... heat dissipation part, 30 ... heat dissipation member, 31 ... contact part, 32 ... heat dissipation part.

Claims (6)

A metal member fixed to the side surface of the liquid crystal display unit;
A fixture comprising a heat dissipating member interposed between the metal member and the side surface and having a thermal conductivity greater than the thermal conductivity of the metal member,
The said heat radiating member has a contact part contacted with the said side surface, and a heat radiating part extended from the said contact part so that it may not overlap with the said side surface. The fixture characterized by the above-mentioned. The fixture according to claim 1, wherein the metal member and the heat radiating member are fixed to each other and integrated. A liquid crystal display device comprising a liquid crystal display unit and a fixture attached to a side surface of the liquid crystal display unit,
The fixture is a metal member fixed to the side surface;
It is interposed between the metal member and the side surface, and comprises a heat radiating member having a thermal conductivity larger than the thermal conductivity of the metal member,
The said heat radiating member has a contact part contacted with the said side surface, and a heat radiating part extended from the said contact part so that it may not overlap with the said side surface. The liquid crystal display device characterized by the above-mentioned. The liquid crystal display device according to claim 3, wherein the heat radiating portion is bent from the contact portion toward the back side of the liquid crystal display unit. The liquid crystal display device according to claim 4, wherein the heat radiating portion is in contact with a back surface of the liquid crystal display unit. The liquid crystal display device according to claim 3, wherein the metal member and the heat dissipation member are fixed to each other and integrated.

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