JP2010113214A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device in which a conductor electrically connecting a ground pattern of a printed circuit board with a metal bezel can be easily attached and detached without disengaging the metal bezel. <P>SOLUTION: The liquid crystal display device includes: a printed circuit board for driving a liquid crystal, the circuit board being disposed between a rim of a liquid crystal display panel and a sidewall of a metal bezel covering the rim, and separated from and approximately in parallel to the sidewall; and a planar conductor electrically connecting the sidewall of the metal bezel and a land of a ground pattern formed on the printed circuit board. An insertion hole is opened in an upper wall of the metal bezel so as to insert the conductor from the outside; and the top end of the conductor inserted into the insertion hole is brought into contact with both of the sidewall of the metal bezel and the land of the ground pattern on the printed circuit board, while the rear end of the conductor is detachably locked to the insertion hole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device with EMI countermeasures taken.

  In recent years, a liquid crystal display device has been used as a display unit for home appliances such as computers and televisions. FIG. 7 is a cross-sectional view schematically showing the main part of the structure of a general liquid crystal display device.

  As shown in the figure, the liquid crystal display panel 2 included in the liquid crystal display device 60 includes a pair of substrates, which are a thin film transistor (TFT) array substrate 21 and a color filter (CF) substrate 22, arranged in parallel and facing each other at a predetermined interval. The liquid crystal is filled between the substrates 21 and 22.

  In general, the TFT array substrate 21 is formed with a plurality of gate wirings, a plurality of source wirings, and pixel electrodes arranged in each region partitioned in a grid pattern by these wirings. A common electrode is formed on the entire surface, and by changing a voltage applied to each pixel electrode and the common electrode, an image can be displayed by driving a liquid crystal for each pixel.

  In the liquid crystal display device 60, the backlight unit 3 is arranged on the back side of the liquid crystal display panel 2. The backlight unit 3 is a device that includes a light source such as a fluorescent lamp, and irradiates the back side of the liquid crystal display panel 2 by adjusting characteristics of light emitted from the light source. The light emitted from the backlight unit 3 is transmitted through the liquid crystal display panel 2 so that an image is displayed on the front side of the liquid crystal display panel 2 in a visible state. Normally, a metal bezel 61 is attached to the liquid crystal display panel 2 so as to cover the upper surface and side surfaces of the peripheral edge portion.

  A printed circuit board (PWB: Printed Wire Board or PCB :) that drives a liquid crystal by supplying a predetermined voltage to the gate wiring and the source wiring formed on the TFT array substrate 21 is provided at the periphery of the liquid crystal display panel 2. Printed Circuit Board) 31 is arranged. For the electrical connection between the printed circuit board 31 and each wiring formed on the TFT array substrate 21, a flexible wiring board 30 having flexibility is used. Usually, a driver IC 28 is provided on the flexible wiring board 30. Has been implemented.

  Among such flexible wiring boards 30, when the driver IC 28 is mounted on a COF (Chip on Film) system, there is no device hole for mounting the driver IC 28, and it is easy to design a narrow wiring pattern pitch. Widely adopted.

  As shown in the figure, the flexible wiring board 30 has wiring patterns 30b and 30b formed on a flexible film substrate 30a, and a driver IC 28 is mounted by the COF method and connected to the wiring patterns 30b and 30b. . In the wiring patterns 30b and 30b, the lead portions 30c and 30d are drawn to the end portion of the film base material 30a. One lead portion 30 c is connected to the land portion of the source wiring 24 </ b> S of the liquid crystal display panel 2 through the anisotropic conductive film 62. The other lead portion 30d is connected to a wiring land portion 31b of a wiring pattern 31a on the printed circuit board 31 to which an image signal and a voltage based on the image signal are transmitted.

  In this case, by bending the flexible wiring board 30 as shown in the drawing, the printed circuit board 31 is arranged in an empty space between the side surface of the backlight unit 3 and the side wall 61b of the metal bezel 61. The width of the upper wall 61a of the frame-shaped metal bezel 61 attached to the liquid crystal display panel 2 can be reduced.

  FIG. 8 shows a plan view of the flexible wiring board 30 before bending, and the liquid crystal display panel 2 and the printed circuit board 31 connected via the flexible wiring board 30. As shown in the figure, a ground pattern 31c is generally formed on the printed circuit board 31 on almost the entire surface except for the circuit such as the wiring land portion 31b of the wiring pattern 31a. The entire surface of the ground pattern 31c is covered with a solder resist film 31e as a protective film for preventing corrosion. In this case, the ground pattern 31c is formed with a plurality of ground land portions 31d that are not covered with the solder resist 31e but exposed in a rectangular shape.

  With the recent increase in size of the liquid crystal display panel 2 and the like, the length of such a printed circuit board 31 has been increased, and the radiation of electromagnetic waves generated from the printed circuit board 31 has increased. Electro Magnetic Interference: An appropriate design for unwanted radiation and electromagnetic radiation is regarded as important.

  For example, as a measure against such EMI, the ground land 31d of the ground pattern 31c of the printed circuit board 31 and the metal bezel 61 are electrically connected at a plurality of locations by using a strip-shaped conductor 63 as illustrated. The generation of electromagnetic waves generated from the printed circuit board 31 can be suppressed.

  As such a conductor 63, a material in which an elastic material 63a such as a sponge as shown is covered with a metal foil 63b or the like is used. In this case, in a state before the flexible wiring board 30 is bent as shown in FIG. 8, the conductor 63 is attached in advance to the ground land portion 31d of the printed circuit board 31 via the conductive adhesive tape 64. After that, as shown in FIG. 7, the metal bezel 61 is assembled so that the conductor 63 is brought into contact with the side wall 61b of the metal bezel 61, and the ground pattern 31c of the printed circuit board 31 and the metal bezel 61 are electrically connected. It can be made to. In addition, the following patent document is mentioned as a prior art document relevant to this invention.

JP 2005-215185 A

  In general, a liquid crystal display device for television, in addition to the backlight unit 3 described above, is a tuner that generates a video signal and an audio signal of a predetermined channel based on the received television radio wave or an input signal input from the outside. Further, a speaker that emits sound based on an audio signal generated by the tuner, and an electric device such as a power source that supplies power to the tuner, the speaker, and the backlight unit are further assembled.

  However, when a test based on the EMI evaluation is performed after these electrical devices are assembled, the metal bezel 61 picks up electromagnetic waves generated from these electrical devices, and these are picked up by the ground pattern 31c of the printed circuit board 31 via the conductors 63. As a result, the ground potential of the ground pattern 31c of the printed circuit board 31 becomes unstable and electromagnetic waves generated from the printed circuit board 31 increase, and as a result, the EMI standard may not be satisfied. there were.

  In such a case, all of the conductor 63 is removed to eliminate the connection portion between the metal bezel 61 and the printed circuit board 31, or part of the conductor 63 is removed to remove the metal bezel 61 and the printed circuit board 31. However, it takes time and effort to remove the attached metal bezel 61 and reassemble the metal bezel 61 just to remove the conductor 63.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a liquid crystal display device in which a conductor for electrically connecting a ground pattern of a printed circuit board and a metal bezel can be easily attached / detached without removing the metal bezel. .

  In order to solve the above-described problems, a liquid crystal display device according to the present invention includes a liquid crystal display panel, and an upper wall and a side wall having an inverted L-shaped cross section that are attached to cover the upper surface and side surfaces of the peripheral edge of the liquid crystal display panel. A frame-shaped metal bezel, and a printed circuit board for driving a liquid crystal disposed between the peripheral edge of the liquid crystal display panel and the side wall of the metal bezel and spaced substantially parallel to the side wall; A plate-like conductor that conductively connects a side wall of the metal bezel and a land portion of a ground pattern formed on the printed circuit board, and the conductor is provided on the upper wall of the metal bezel from the outside. An insertion hole to be inserted is formed, and the tip of the conductor inserted into the insertion hole is in contact with both the side wall of the metal bezel and the land portion of the ground pattern of the printed circuit board. The back end of the body It is an gist to be locked detachably engaged with the serial insertion hole.

  According to the liquid crystal display device having such a configuration, since the metal bezel attached to the liquid crystal display panel can be removed without attaching the metal bezel, that is, the conductor can be attached / detached as needed. Therefore, it is possible to easily adjust the EMI countermeasures in the liquid crystal display device.

  At the front end of the conductor, a ground contact portion that contacts a land portion of the ground pattern of the printed circuit board is formed protruding toward the land portion side, and is in contact with a side wall of the metal bezel. If the bezel contact portion to be formed protrudes toward the side wall, the conductive connection between the side wall of the metal bezel and the land portion of the ground pattern formed on the printed circuit board is good via the conductor. To be made.

  In this case, if the surface of the ground contact portion of the conductor is formed in an arc shape, the contact with the land portion of the ground pattern of the printed circuit board can be improved, and the metal bezel When the conductor is inserted or removed from the insertion hole formed in the upper wall, it is possible to prevent the other electric circuit formed on the printed circuit board from being damaged.

  Furthermore, if the surface of the ground contact portion of the conductor is formed in a mirror shape, the contact with the land portion of the ground pattern of the printed circuit board can be further improved, and the metal bezel When the conductor is inserted into or removed from the insertion hole formed in the upper wall, it is further prevented that other electric circuits formed on the printed circuit board are damaged.

  If the ground contact portion and the bezel contact portion of the conductor are elastically deformable, the contact between the side wall of the metal bezel and the land portion of the ground pattern of the printed circuit board is made elastic. Even when an external force such as vibration is applied, it is possible to maintain a state in which the side wall of the metal bezel and the land portion of the ground pattern formed on the printed circuit board are conductively connected via the conductor.

  According to the present invention having the above configuration, a frame-shaped metal having a liquid crystal display panel, and an upper wall and a side wall having an inverted L-shaped cross section that are attached so as to cover the upper surface and side surfaces of the peripheral edge of the liquid crystal display panel. A bezel made of liquid crystal, a printed circuit board for driving a liquid crystal disposed between the peripheral portion of the liquid crystal display panel and the side wall of the metal bezel and spaced substantially parallel to the side wall, and the side wall and the print of the metal bezel In a liquid crystal display device having a plate-like conductor that is electrically connected to a land portion of a ground pattern formed on a circuit board, an insertion hole through which the conductor is inserted from the outside is opened on the upper wall of the metal bezel The front end of the conductor formed and inserted into the insertion hole is in contact with both the side wall of the metal bezel and the land portion of the ground pattern of the printed circuit board, and the rear end of the conductor is detachable from the insertion hole. Configuration to be locked Because, without removing the deposited metal bezel to the liquid crystal display panel, enabling the mounting and removal of the conductor if necessary, it can be easily adjusted for EMI in the liquid crystal display device.

  Hereinafter, an embodiment of a liquid crystal display device according to the present invention will be described with reference to the drawings. 1 is an exploded perspective view showing a schematic configuration of a liquid crystal display device, FIG. 2 is a diagram schematically showing the structure of a liquid crystal display panel, and FIGS. 3 and 4 are sectional views showing the internal structure of the liquid crystal display device. is there. In the following description, the front side refers to the upper side of the liquid crystal display device shown in FIG. 1, and the rear side refers to the lower side of the liquid crystal display device shown in FIG.

  As shown in FIG. 1, the liquid crystal display device 1 includes a liquid crystal display panel 2 and a backlight unit 3 disposed on the back side of the liquid crystal display panel 2. The liquid crystal display panel 2 has a configuration in which a pair of substrates including a thin film transistor (TFT) array substrate and a color filter (CF) substrate are arranged in parallel to each other with a predetermined gap, and the gap is filled with liquid crystal. The back side is irradiated with light from the backlight unit 3. The irradiated light is transmitted through the liquid crystal display panel 2 so that an image is displayed in a visible state on the front side of the liquid crystal display panel 2.

  The backlight unit 3 for irradiating light onto the liquid crystal display panel 2 includes a shallow box-shaped backlight chassis 4, and a straight tube type CCFL (Cold Cathode) as a light source lamp is provided on a lamp housing surface 4 a inside thereof. A plurality of Fluorescent Lamps (cold cathode fluorescent lamps) 5 are arranged. Each CCFL 5 is fixed to the backlight chassis 4 by electrode holders 6 and 6 attached to both ends and a lamp clip 7 that holds the middle part.

  An optical sheet 8 is disposed on the upper side of the CCFL 5. The optical sheet 8 is a diffusion plate, a diffusion sheet, a lens sheet, a polarization reflection sheet, etc. in order from the bottom in order to adjust the characteristics of light incident on the liquid crystal display panel 2 from the CCFL 5 and light reflected from the reflection sheet 9. These plate-like or sheet-like optical members are stacked. The optical sheet 8 is held by the frame 10 on the placement part 4f on the long side of the backlight chassis 4 and the placement part 4g on the short side. The frame 10 is a metal or resin member formed into an open quadrilateral. A side wall portion 10b is provided on the outer peripheral edge of the frame 10 so as to rise toward the back side, and each side has a substantially inverted L-shaped cross section.

  The backlight chassis 4 includes a flat bottom plate portion 4b serving as a lamp receiving surface 4a, a chassis member 11 having long side wall portions 4c and 4c formed by sheet metal processing of a metal plate material, and a short side wall portion. 4d and 4d are comprised by the side holder members 12 and 12 shape | molded by the resin material. The backlight chassis 4 includes a lamp receiving surface 4a formed by a bottom plate portion 4b and mounting portions 4f and 4g formed at upper ends of side wall portions 4c and 4d. The optical sheet 8 described above is placed on the placement portions 4f and 4g, and the frame 10 is attached and held.

  Further, a white reflection sheet 9 is laid on the back side of the CCFL 5, that is, on the bottom plate portion 4 b of the backlight chassis 4, and the light irradiated from the CCFL 5 to the reflection sheet 9 side by the reflection sheet 9 is applied to the liquid crystal display panel 2. Reflected to the side. An inverter circuit board 16 that generates a high-voltage pulse voltage that drives the CCFL 5 and a control circuit board 17 that controls the driving of the liquid crystal display panel 2 are attached to the back surface of the backlight chassis 4. The inverter circuit board 16 and the control printed circuit board 17 are covered with an inverter circuit board cover 18 and a control circuit board cover 19, respectively.

  On the front side of the frame 10 of the backlight unit 3 having such a configuration, the liquid crystal display panel 2 is placed and held by a frame-shaped metal bezel 13.

  As shown in the schematic diagram of FIG. 2, the liquid crystal display panel 2 is provided with a TFT array substrate 21 and a CF substrate 22 facing each other at a predetermined interval via liquid crystal.

  On the CF substrate 22, a common electrode (not shown), a grid-like black matrix, and color filters such as red, blue, and green are formed on almost the entire surface. In the TFT substrate 21, a plurality of source lines 24 </ b> S extending in the vertical direction and arranged in parallel intersect with a plurality of gate lines 24 </ b> G extending in the horizontal direction and arranged in parallel. Is formed. In addition, pixel electrodes 23 are respectively formed in the pixel regions partitioned by the source wiring 24S and the gate wiring 24G in a grid pattern. A TFT 25 serving as a switching element is disposed in the vicinity of the intersection of both wirings. In this case, the source line 24S supplies a voltage based on the image signal to the pixel electrode 23, and the gate line 24G turns on and off the TFT 25.

  The source electrode S of the TFT 25 is connected to the source line 24S, and the gate electrode G of the TFT 24 is connected to the gate line 24G. The drain electrode D of the TFT 24 is connected to the pixel electrode 23. The gate line 24G is connected to the gate driver IC 27, and the source line 24S is connected to the source driver IC 28. These driver ICs 27 and 28 are connected to the control circuit board 17 and controlled.

  The gate driver IC 27 connected to the gate wiring 24G is supplied with the scanning signal voltage Vg by the control circuit board 17, and the scanning signal voltage Vg is applied from the gate driver IC 27 to each gate wiring 24G. Yes. An image signal and an image signal voltage Vs based on the signal are supplied from the control circuit board 17 to the source driver IC 28 connected to the source wiring 24S, and the image signal voltage Vs is supplied from the source driver IC 28 to each source wiring 24S. Is to be applied.

  In this case, the gate driver IC 27 selects one gate wiring 24G, applies the scanning signal voltage Vg, and turns on all the TFTs 25 connected to the selected gate wiring 24G. At this time, the source driver IC 28 applies the image signal voltage Vs according to the driving state of each pixel to all the source wirings 24 </ b> S, so that the image is applied to all the pixel electrodes 23 connected to each TFT 25. The signal voltage Vs is charged.

  At this time, the potential difference between the common voltage Vcom applied to the common electrode and the image signal voltage Vs charged to the pixel electrode 23 becomes the liquid crystal drive voltage VLC for driving the liquid crystal 26, and the liquid crystal 26 is driven by the liquid crystal drive voltage VLC. At the same time, the liquid crystal driving voltage VLC is held by the liquid crystal 26 and the holding capacitor CS. Then, the gate driver IC 27 sequentially selects and scans each gate wiring 24G from the top as indicated by an arrow 40 in the figure, so that all pixels are driven to display an image for one frame, that is, one screen. Is done. A moving image is displayed by repeating this at a predetermined frame frequency (frequency of repeated scanning of one screen).

  As shown in FIG. 1, a plurality of flexible wiring boards 29 are connected to one short side of the four sides of the rectangular liquid crystal display panel 2, and a plurality of flexible wiring boards 29 are also connected to one long side of the four sides. A flexible wiring board 30 is connected. A gate driver IC 27 that supplies the scanning signal voltage Vs to the above-described gate wiring 24G is mounted on the flexible wiring board 29. In addition, a source driver IC 28 that supplies an image signal voltage Vs based on an image signal to the source wiring 24 </ b> S described above is mounted on the flexible wiring board 30.

  In this case, one printed circuit board 31 is connected to each of the five flexible wiring boards 30 on which the source driver IC 28 is mounted. The two printed circuit boards 31 are connected to the control circuit board 17 via a cable (not shown). The flexible wiring board 29 on which the gate driver IC 27 is mounted is connected to the printed circuit board 31 via an internal wiring (not shown) formed on the liquid crystal display panel 2 and a part of the wiring of the flexible wiring board 30.

  The printed circuit board 31 is formed in an elongated shape, for example, a rectangular shape as illustrated, and is disposed along the peripheral edge of the liquid crystal display panel 2. Various wiring patterns are formed along the longitudinal direction on the surface of the printed circuit board 31 and the inner layers. As shown in the figure, a plurality of flexible wiring boards 30 are connected to a single printed circuit board 31, and a scanning signal voltage Vg is supplied to the gate driver IC 27 and an image signal voltage Vs is supplied to the source driver IC 28. Each can be distributed.

  As shown in FIGS. 1 and 3, the metal bezel 13 is a member having a function of holding or protecting the liquid crystal display panel 2 and is attached so as to cover the upper surface and side surfaces of the peripheral edge of the liquid crystal display panel 2. Is done. The metal bezel 13 is formed in a quadrilateral frame shape opened from a metal plate material such as stainless steel by pressing or the like. In this case, each side of the metal bezel 13 has an inverted L-shaped cross section having an upper wall 13a and a side wall 13b, and the side wall 13b is erected toward the back side.

  Further, a plurality of insertion holes 13c into which the flat conductors 14 are inserted are formed in a portion near the side wall 13b of the upper wall 13a of the metal bezel 13 on the side where the printed circuit board 31 is disposed. In this case, four insertion holes 13c are formed corresponding to the number of ground land portions 31d, 31d, 31d, 31d formed on each of the two printed circuit boards 31, 31, respectively. Four conductors 14 to be inserted into the insertion holes 13c are also provided.

  After the liquid crystal display device 1 is assembled as shown in FIG. 3, the printed circuit board 31 is substantially parallel to the side wall 13 b between the peripheral edge of the liquid crystal display panel 2 and the side wall 13 b of the bezel 13. They are spaced apart. In this case, the printed circuit board 31 is fixed to the side wall 10b of the frame 10 included in the backlight unit 3 by screws or the like.

  A procedure for assembling the liquid crystal display device 1 having such a configuration will be described. First, the reflective sheet 9 is laid on the lamp accommodating surface 4 a of the chassis member 11 provided in the backlight chassis 4, and the CCFL 5 is fixed to the front side of the reflective sheet 9 using the electrode holders 6 and 6 and the lamp clip 7. Next, the side holder members 12 and 12 are mounted along the short sides of the backlight chassis 4 so that both ends of the CCFL 5 are covered with the electrode holders 6 and 6. Then, the optical sheet 8 is mounted on the mounting portions 4 f and 4 g of the backlight chassis 4 assembled in this manner, and the frame 10 is mounted from the front side of the optical sheet 8.

  Next, the liquid crystal display panel 2 to which the printed circuit board 30 is connected via the flexible wiring board 29 is placed on the front side of the frame 10, that is, the upper wall 10a. At that time, the flexible wiring board 30 on which the driver IC 28 is mounted is bent toward the back side, and the printed circuit board 31 is fixed to the outer surface of the side wall 10 b of the frame 10. Thereafter, a metal bezel 13 is attached to the front side of the liquid crystal display panel 2, and the metal bezel 13 and the chassis member 11 of the backlight chassis 4 are fixed by screws or the like.

  Next, the inverter circuit board 16 and the control circuit board 17 are fixed to the back side of the backlight chassis 4, and the inverter circuit board cover 16 and the control circuit board cover 17 are mounted so as to cover the respective circuit boards. The inverter circuit board 16 and the CCFL 5 are connected by a cable (not shown), and the control circuit board 17 and the printed circuit board 31 are connected by a cable (not shown).

  The operation of the liquid crystal display device 1 assembled in this way will be described. The inverter circuit board 16 generates a high voltage pulse voltage and supplies it to each CCFL 5. As a result, each CCFL 5 emits light. The light emitted by each CCFL 5 is adjusted by the optical sheet 8 and transmitted through the optical sheet 8 together with the light reflected by the reflective sheet 9. The light transmitted through the optical sheet 8 is transmitted from the back side of the liquid crystal display panel 2 toward the front side.

  At this time, the control circuit board 17 generates signals for controlling the driver ICs 27 and 28, and the generated control signals are supplied to the driver ICs 27 and 28 mounted on the flexible wiring boards 29 and 30 via the printed circuit board 31. To be supplied. The driver ICs 27 and 28 drive the liquid crystal display panel 2 based on the control signal. As a result, the display image is made visible on the front side of the liquid crystal display panel 2.

  Such a liquid crystal display device 1 is provided with four conductors 14 as an EMI countermeasure for suppressing electromagnetic waves generated from the printed circuit board 31. As shown in FIG. 1, four insertion holes 13c are formed in the upper wall 13a of the long side of the metal bezel 13 along the longitudinal direction, and the conductor 14 is inserted into each insertion hole 13c. Thus, as shown in FIG. 3, the ground land 31d of the ground pattern 31c formed on the printed circuit board 31 and the side wall 13b of the metal bezel 13 can be electrically connected. 4 shows a state in which the conductor 14 is removed from the liquid crystal display device 1 shown in FIG.

  FIG. 5 is an external perspective view of the conductor 14. As shown in the drawing, the conductor 14 is formed in a substantially rectangular shape by punching and bending a metal plate, and a ground contact portion 14b and a bezel contact portion 14c are provided at the lower end of the flat plate portion 14a. . The ground contact portion 14b is formed so as to protrude outward in an arc shape with respect to one surface of the flat plate portion 14a of the conductor 14, and the bezel contact portion 14c is formed with respect to the other surface of the flat plate portion 14a of the conductive material 14. And projecting in an arc shape in the outer direction. In this case, the ground contact portion 14b is disposed at the center of the lower end of the flat plate portion 14a, and the bezel contact portions 14c and 14c are disposed on both sides thereof.

  Further, slits 14d and 14d that are notched upward from the lower end are provided between the ground contact portion 14b and the bezel contact portions 14c and 14c, and the ground contact portion 14b and the bezel contact portions 14c and 14c. Each can be elastically deformed inward. Therefore, as shown in FIG. 3, the ground contact portion 14b is elastically contacted with the ground land portion 31d of the ground pattern 31c formed on the printed circuit board 31, and the bezel contact portions 14c and 14c are made of a metal bezel. The inner wall of the 13 side walls 13b is elastically contacted. Thereby, even when an external force such as vibration is applied to the assembled liquid crystal display device 1, the side wall 13 b of the metal bezel 13 and the ground land portion 31 d of the printed circuit board 31 are conductively connected via the conductor 14. Can be maintained.

  In this case, as shown in the figure, a mirror surface portion 14e is formed on the contact surface of the ground contact portion 14b that is in contact with the ground land portion 30d of the printed circuit board 31. Thus, by making the contact surface of the ground contact portion 14a with the ground land portion 30d into a mirror surface, the contact with the ground land portion 30d of the printed circuit board 31 can be improved, and the metal bezel 13 can be made. When the conductor 14 is inserted or removed from the insertion hole 13c formed in the upper wall 13a, other wiring patterns formed on the printed circuit board 31 may be damaged, or the solder resist film 31e may It is prevented from peeling off.

  Further, locking pieces 14f, 14f, and 14f are provided at the upper end of the flat plate portion 14a of the conductor 14. A locking projection 14g that protrudes in an arc shape outwardly from both surfaces of the flat plate portion 14a is formed in the middle of each locking piece 14f. In this case, the locking projection 14g of the locking piece 14f disposed in the center is formed to protrude outward from one surface of the flat plate portion 14a, and the locking pieces 14f and 14 disposed on both sides are formed. The locking projections 14g and 14g are formed to protrude outward from the other surface of the flat plate portion 14a. Moreover, the latch release operation part 14h extended so that it might protrude outside was formed in the upper end of each latching piece 14f.

  Between each of the locking pieces 14f, slits 14i and 14i that are notched downward from the upper end are provided, and each of the locking pieces 14f can be elastically deformed inward. As shown in FIG. 3, when each locking piece 14f of the conductor 14 is inserted into an insertion hole 13c formed in the upper wall 13a of the metal bezel 13, an upper edge and a lower edge of the insertion hole 13c are formed. However, it is sandwiched and locked between the unlocking operation portion 14h and the locking projection 14g of each locking piece 14f.

  A procedure for inserting such a conductor 14 into the insertion hole 13c of the metal bezel 13 will be described. First, the ground contact portion 14b and the bezel contact portion 14c at the tip of the conductor 14 are inserted into the insertion hole 13c from above and passed through the insertion hole 13c. Next, while holding each locking release operation portion 14h, each locking piece 14f is bent inward, and the portion where the locking projection 14g is formed is inserted through the insertion hole 13c. And when the latching convex part 14g passes the insertion hole 13c, each latching piece 14f of the rear end of the conductor 14 is removed from the metal bezel 13 by stopping the holding of each latching release operation part 14h. It is locked in the insertion hole 13c. At this time, the ground contact portion 14 b and the bezel contact portion 14 c at the tip of the conductor 14 are in contact with the ground land portion 30 d and the side wall 13 b of the metal bezel 13. In addition, the conductor 14 can be removed as shown in FIG. 4 by following the procedure opposite to the procedure described above.

  Next, a television receiver provided with such a liquid crystal display device 1 will be briefly described. FIG. 6 is an exploded perspective view schematically showing an example of the configuration of the television receiver 50 including the liquid crystal display device 1 according to the above-described embodiment. The television receiver 50 includes a tuner 52 that generates a video signal and an audio signal of a predetermined channel based on a received radio wave and an input signal input from the outside, and a video based on the video signal generated by the tuner 52. A liquid crystal display device 1 for display, a speaker 54 that emits sound based on an audio signal generated by the tuner 52, and a power supply substrate 53 that supplies power to the tuner 52, the liquid crystal display device 1, and the speaker 54 are provided.

  As the tuner 52, a conventional general terrestrial (analog or digital or both) tuner, BS tuner, CS tuner, or the like is used. The liquid crystal display device 1, the tuner 52, the speaker 54, and the power supply substrate 53 are housed in a casing constituted by the front side cabinet 51 a and the back side cabinet 51 b, and are further supported in a standing state by a stand 55.

  In the liquid crystal display device 1 described above, the conductor 14 is provided as an EMI countermeasure for the printed circuit board 31, but a tuner 52, a speaker 54, and a power supply substrate 53 as in the configuration of the television receiver 50 shown in FIG. 6. When a test by EMI evaluation is performed after assembling such electrical equipment, the metal bezel 13 picks up electromagnetic waves generated from these electrical equipment, and these are picked up by the ground pattern 31c of the printed circuit board 31 via the conductor 14. As a result of being applied as noise, the ground potential of the ground pattern 31c of the printed circuit board 31 becomes unstable, and electromagnetic waves generated from the printed circuit board 31 increase, and as a result, the EMI standard may not be satisfied. .

  In such a case, all of the four conductors 14 are removed to eliminate the connection portion between the metal bezel 13 and the printed circuit board 31, or a part of the four conductors 14 is removed to remove the metal bezel 13 from the printed circuit board 31. For example, the number of connection points with the printed circuit board 31 is reduced. In this case, since the conductor 14 can be removed without removing the metal bezel 13, the conductor 14 was attached only to remove the conductor 63 as in the prior art described in FIGS. The work of removing the metal bezel 61 and reassembling the metal bezel 61 is eliminated.

  According to the liquid crystal display device 1 described above, the conductor 14 can be attached and detached as needed without removing the metal bezel 13 attached to the liquid crystal display panel 2, that is, with the attached state. The EMI countermeasures in the liquid crystal display device 1 can be easily adjusted.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to such embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement in a various aspect. For example, the conductor 14 is in contact with both the side wall 13b of the metal bezel 13 and the ground land portion 31d of the ground pattern 31c formed on the printed circuit board 31, and the rear end of the conductor 14 is the metal bezel 13. It only needs to have a shape that can be detachably locked in the insertion hole 13c formed in the upper wall 13a, and is not limited to the shape described above, and various shapes can be employed.

1 is an exploded perspective view showing a schematic configuration of a liquid crystal display device according to an embodiment of the present invention. It is the figure which showed typically the structure of the liquid crystal display panel with which the liquid crystal display device of FIG. 1 is provided. It is the figure which showed the cross section after the assembly of the liquid crystal display device of FIG. It is the figure which showed the state which removed the conductor with which the liquid crystal display device of FIG. 3 is provided. It is the external appearance perspective view which expanded and showed the conductor with which the liquid crystal display device of FIG. 1 is provided. It is the disassembled perspective view which showed typically the structure of the television receiver provided with the liquid crystal display device of FIG. It is the figure which showed the cross section of the liquid crystal display device used conventionally. It is the top view which showed the connection structure of the liquid crystal display panel with which the liquid crystal display device of FIG. 7 is equipped, and a printed circuit board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal display device 2 Liquid crystal display panel 3 Backlight unit 13 Bezel 13a Upper wall 13b Side wall 13c Insertion hole 14 Conductor 14b Ground contact part 14c Bezel contact part 14e Mirror surface part 14f Locking piece 31 Printed circuit board 31c Ground pattern 31d Ground land Part

Claims (5)

  A liquid crystal display panel, a frame-shaped metal bezel having an upper wall and a side wall having an inverted L-shaped cross section, which are attached so as to cover an upper surface and a side surface of a peripheral edge of the liquid crystal display panel; A printed circuit board for driving a liquid crystal disposed between a peripheral portion and a side wall of the metal bezel and spaced substantially parallel to the side wall, and formed on the side wall of the metal bezel and the printed circuit board. A plate-like conductor that is electrically connected to the land portion of the ground pattern, and an insertion hole for inserting the conductor from the outside is formed in the upper wall of the metal bezel, and is inserted into the insertion hole. The front end of the conductor is in contact with both the side wall of the metal bezel and the land portion of the ground pattern of the printed circuit board, and the rear end of the conductor is removably locked in the insertion hole. Liquid characterized by Display device.   A ground contact portion that comes into contact with a land portion of the ground pattern of the printed circuit board protrudes toward the land portion side at the tip of the conductor, and the bezel that comes into contact with the side wall of the metal bezel The liquid crystal display device according to claim 1, wherein the contact portion is formed to protrude toward the side wall.   The liquid crystal display device according to claim 2, wherein a surface of the ground contact portion of the conductor is formed in an arc shape.   4. The liquid crystal display device according to claim 2, wherein a surface of the ground contact portion of the conductor is formed in a mirror shape.   The liquid crystal display device according to claim 2, wherein the ground contact portion and the bezel contact portion of the conductor are elastically deformable.

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