JP2009251260A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which is effectively thinned when fixing a printed circuit board to a rear frame. <P>SOLUTION: A caulking fixing part 12 and a pedestal 13 for screwing are formed in a rear frame 2 provided in a backlight unit, by cutting and bending. A printed circuit board 5 is stacked on the rear frame 2, and the caulking fixing part 12 has a caulking wall part 12b caulked to the outer surface side of the printed circuit board 5 and has a screwing wall part 12c fixed to the pedestal 13 for screwing by a screw 6, whereby the printed circuit board 5 is fixed to the rear frame 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device having an improved structure for fixing a printed circuit board connected to a display panel to a backlight unit for illuminating the display panel.

  2. Description of the Related Art Conventionally, there is a liquid crystal display device in which a liquid crystal panel to which a printed circuit board on which a liquid crystal driving driver is mounted is connected and a backlight are sandwiched between a plastic case and a metal frame (see, for example, the prior art in Patent Document 1). .

  In this case, since there is a problem in thinning, a liquid crystal display device has been proposed in which a liquid crystal panel is sandwiched between a first metal frame and a second metal frame to improve them (for example, Patent Document 1). reference).

JP-A-6-3687

  By the way, as a premise of the present invention, there is a case where it is desired to fix a printed circuit board connected to the liquid crystal panel to a rear frame that covers the back side of the backlight unit.

  For example, as shown in FIG. 9 and FIG. 10, since there is a reflection sheet 3 and a light guide plate 4 on the inner surface side of the rear frame 2 in the backlight unit 1, a liquid crystal panel (not shown) and When a printed circuit board (PCB) 5 connected via a COF (Chip On Film) (not shown) is fixed to the rear frame 2 with screws 6, the mounting component 7 on the printed circuit board 5 is disposed only on the outer surface side. Even when there is no mounting component 7 on the back side, it is necessary to secure a height corresponding to the axial length L of the screw 6 so as not to affect the reflection sheet 3.

  That is, since the axial length L of the screw 6 is longer than the sum of the thickness T of the rear frame 2 and the thickness t of the printed circuit board 5, the screw base 8 of the rear frame 2 to which the screw 6 is fastened is It is necessary to provide a predetermined height H.

  For example, when the thickness T of the rear frame 2 is 0.8 mm, the thickness t of the printed circuit board 5 is 0.5 mm, and the shaft length L of the screw 6 is 3 mm, the height H of the screw fixing base 8 is L−T. It is necessary to secure 1.7 mm or more at −t or more. When the maximum height h of the mounting component 7 mounted on the printed circuit board 5 is 2 mm, the total height S from the rear surface of the rear frame 2 is H + t + h, which is 4.2 mm or more.

  That is, the total height S from the rear surface of the rear frame 2 is the sum of the height H of the screwing base 8, the thickness t of the printed circuit board 5, and the height h of the mounting component 7 of the mounting component 7. Therefore, there arises a problem that the overall thickness of the liquid crystal display device is increased.

  In view of the above problems, the present invention has an object to provide a display device that is effectively reduced in thickness when a printed circuit board is fixed to a rear frame.

  In a display device in which a printed circuit board connected to a display panel is fixed to a rear frame provided in a backlight unit, a caulking fixing portion is cut and raised on the rear frame, and the printed circuit board is overlapped on the rear frame. The caulking fixing portion is caulked to the outer surface side of the printed circuit board to fix the printed circuit board.

  According to the display device of the present invention, since the caulking fixing portion formed by cutting and raising the rear frame is caulked to the outer surface side of the printed circuit board superimposed on the rear frame, the printed circuit board is fixed. The total height protruding to the back side of the frame is the sum of the thickness of the printed circuit board and the mounting components mounted on it, as described above, plus the height of the screw base for fixing the printed circuit board. Instead, it is determined by the higher one of the sum of the thickness of the printed circuit board and the height of the mounted components mounted on it, or the height of the caulking fixing part for fixing the printed circuit board. There is an advantage that the thickness can be effectively reduced.

<Embodiment 1>
Embodiment 1 of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same component as the above-mentioned. That is, FIG. 1 to FIG. 5 show a backlight unit 1 portion in a liquid crystal display device as an example of a display device, and irradiates a liquid crystal panel (not shown) as an example of a display panel from the back side as described above. The rear frame 2 made of a metal frame is disposed so as to cover the back side of the reflective sheet 3 and the light guide plate 4. Further, a middle frame 10 made of metal and having an appropriate thickness is disposed on the inner surface side of both end portions of the rear frame 2.

  A mounting component 7 for driving such as a driver for driving a liquid crystal is mounted on the printed circuit board 5, and the liquid crystal panel and the printed circuit board 5 are connected via a TCP (Tape Carrier Package) (not shown). .

  In addition, insertion holes 5a through which the shafts of the screws 6 are inserted are formed at both side ends of the printed circuit board 5 attached in a superposed manner on the back side of the rear frame 2 so as to correspond to the positions of the middle frames 10, respectively. ing. Then, corresponding to each insertion hole 5 a of the printed circuit board 5, an insertion hole 2 a through which the shaft portion of the screw 6 is inserted is formed at a predetermined position corresponding to the position of the middle frame 10 of the rear frame 2.

  Each middle frame 10 is formed with a female screw hole (not shown) to which the screw 6 is screwed, corresponding to the position of each insertion hole 2a.

  Further, the caulking fixing portion 12 and the screw fixing base corresponding to the respective positions in the vicinity of the plurality of portions to which the edge portions of the printed circuit board 5 are fixed at the positions covering the reflection sheet 3 and the light guide plate 4 in the rear frame 2. 13 are cut and raised.

  As shown in FIG. 2, each caulking fixing portion 12 includes a standing wall portion 12 a that is cut and raised at a substantially right angle with respect to the back surface that is the back surface side of the rear frame 2. One side portion is provided with a caulking wall portion 12b protruding to one side. Moreover, the screwing wall part 12c which protrudes to the side is provided in the lower edge part of the crimping wall part 12b. An insertion hole 12d through which the shaft portion of the screw 6 is inserted is formed at the projecting end portion of the screwing wall portion 12c.

  Then, as shown by an imaginary line in FIG. 2, the edge portion of the printed circuit board 5 is rear framed by crimping the caulking wall section 12 b in the caulking fixing section 12 to the outer surface side of the printed circuit board 5. 2 is held in a pressed state on the back surface. At this time, as shown in FIG. 3, the overhanging end portion of the screwing wall portion 12 c is superposed on the base portion 13 a of the screwing base 13. Further, a female screw hole 13b into which the screw 6 is screwed is formed in the pedestal portion 13a of the screw pedestal 13 so as to correspond to the position of the insertion hole 12d formed in the screwing wall portion 12c by tapping or the like. Yes.

  When the printed circuit board 5 is fixed to the rear surface side of the rear frame 2, as shown in FIG. 1, the printed circuit board 5 is superposed on the rear frame 2, and the insertion hole 5a of the printed circuit board 5 and the rear frame 2 are formed. Each screw 6 is screwed and fastened to the female screw hole of each middle frame 10 through the insertion hole 2a.

  Next, as shown by phantom lines in FIG. 2, the caulking wall portions 12 b of the caulking fixing portions 12 are caulked on the outer surface side of the printed board 5 superimposed on the rear frame 2, and the edges of the printed board 5 To fix. By the caulking of the caulking wall portion 12b, as shown in FIG. 3, the screwing wall portion 12c of the caulking fixing portion 12 and the pedestal portion 13a of the screwing base 13 are superposed.

  In this state, as shown in FIG. 4, by screwing and fastening the screw 6 to the female screw hole 13b of the pedestal part 13a through the insertion hole 12d of the screwing wall part 12c, the screwing wall part 12c is The printed board 5 is fixed to the rear frame 2 by being screwed to the screw base 13.

  The present embodiment is configured as described above. In the state where the printed circuit board 5 is fixed to the rear surface side of the rear frame 2, as shown in FIG. 5, printing by the caulking fixing portion 12 and the screw fixing base 13 is performed. The total height S1 of the fixed portion of the substrate 5 from the rear surface of the rear frame 2 is the total height of the height H of the screw fixing base 13, the thickness T of the rear frame 2, and the head thickness U of the screw 6. Become. For example, as described above, when the head thickness U of the screw 6 is 0.1 mm, the total height S1 may be 2.3 mm or more.

  On the other hand, the total height S2 from the rear surface of the rear frame 2 on the printed circuit board 5 side is the total height of the thickness t of the printed circuit board 5 and the height h of the mounted component 7. For example, when the same as described above, the total height S2 is 2.5 mm.

  As described above, since the total height S1 of the fixing portion formed by the crimping fixing portion 12 and the screw base 13 and the total height S2 on the printed circuit board 5 side are present without affecting each other, either The dimension of the total height is defined by one higher height. Therefore, as described above, the total height of the printed circuit board 5 side and the height of the screw base 8 are not the total height, and the thickness of the liquid crystal module can be reduced, and the thinning of the liquid crystal display device is effective. There is an advantage that can be achieved. Therefore, the liquid crystal display device can be made compact when packaging.

  Further, since the screwing wall portion 12c is screwed to the screwing base 13 with the caulking wall portion 12b of the caulking fixing portion 12 being caulked, loosening of the caulking wall portion 12b in the caulking state can be effectively prevented. Accordingly, there is an advantage that the durability of the fixed state of the printed circuit board 5 with respect to the rear frame 2 is excellent.

  Furthermore, since the rear frame 2 has a structure in which the crimping fixing portion 12 and the screwing base 13 are cut and raised, a fixing structure for the printed circuit board 5 can be provided without increasing the number of components.

<Embodiment 2>
6 and 7 show the second embodiment, and the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In other words, according to the present embodiment, the notch-like slits 5 b are formed in the edge portion of the printed circuit board 5 corresponding to the positions where the respective caulking wall portions 12 b of the respective caulking fixing portions 12 are caulked. Further, a positioning wall portion 12e that protrudes to the side corresponding to the lower edge portion of the crimping wall portion 12b to be crimped on the printed circuit board 5 is further provided, and the positioning wall portion 12e protrudes to the lower surface side. The engaging protrusion 12f is integrally formed by press molding or the like.

  When the caulking wall portion 12b of the caulking fixing portion 12 is caulked to the outer surface side of the printed circuit board 5, the engaging protrusion 12f enters the slit 5b of the printed circuit board 5 and engages therewith. .

  Therefore, according to the present embodiment, when the printed circuit board 5 is fixed to the rear frame 2, not only the same effects as those of the first embodiment are obtained, but also the engagement protrusion 12f of the caulking fixing part 12 is formed on the printed circuit board. 5 is in a state of entering and engaging with the slits 5b, the positional deviation of the printed circuit board 5 can be effectively prevented, and the printed circuit board 5 can be more firmly fixed.

<Embodiment 3>
FIG. 8 shows the third embodiment, and the same components as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  That is, according to the present embodiment, the screwing wall portion 12c and the positioning wall portion 12e in the caulking fixing portion 12 are continuously integrated with each other.

  Therefore, according to the present embodiment, when the printed circuit board 5 is fixed to the rear frame 2, not only the same effects as those of the second embodiment are obtained, but the screwing wall portion 12c and the positioning wall portion 12e are simultaneously provided. It can be processed, making it easy to manufacture, and has an advantage of excellent manufacturing efficiency.

It is a principal part disassembled perspective view which shows Embodiment 1 which concerns on this invention. It is a perspective view which shows a crimping | fixing part. It is fixing operation explanatory drawing of the same caulking part. It is fixing operation explanatory drawing of the same caulking part. It is sectional explanatory drawing of an assembly state. FIG. 6 is a perspective view showing a main part of a second embodiment. It is the sectional view on the AA line of FIG. FIG. 10 is a perspective view showing a main part of a third embodiment. It is a principal part disassembled perspective view which shows the technique used as a premise. It is sectional explanatory drawing of the same assembly state.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Backlight unit, 2 rear frame, 5 printed circuit board, 12 caulking fixing | fixed part, 12b caulking wall part, 12c screwing wall part, 12e positioning wall part, 12f engaging protrusion, 13 screwing base.

Claims (3)

In the display device in which the printed circuit board connected to the display panel is fixed to the rear frame provided in the backlight unit,
A caulking fixing part is cut and raised in the rear frame,
The display device, wherein the printed circuit board is superposed on the rear frame, and the printed circuit board is fixed by crimping the caulking fixing portion on an outer surface side of the printed circuit board. The display device according to claim 1,
A display device, wherein a screw base is cut and raised on the rear frame, and the crimping fixing portion is screwed to the screw base in the crimped state. The display device according to claim 2,
A display device, wherein a slit is formed at an edge of the printed circuit board, and an engagement protrusion that enters the slit when the crimping fixing part is crimped is provided in the crimping fixing part. .

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