KR100529101B1 - Plasma display device - Google Patents

Abstract

The present invention relates to a plasma display panel in which a high-efficiency cooling device is attached to a chip on film (COF) that applies an address voltage to a panel, thereby enhancing heat dissipation effect of the chip on film.

The cooling device includes a first heat dissipation unit including a plurality of heat dissipation ribs; A second heat dissipation unit installed at a predetermined distance from the first heat dissipation unit and having a plurality of heat dissipation plates for heat dissipation; At least one heat pipe serving as a heat conducting medium between the first and second heat dissipating portions while mechanically connecting the first heat dissipating portion and the second heat dissipating portion.

Description

Plasma display device {PLASMA DISPLAY DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device, and more particularly, to a plasma display device in which a high efficiency cooling device is attached to a connection member for applying a voltage into a panel to enhance a heat dissipation effect of an integrated circuit mounted on the connection member.

As is well known, a plasma display panel (PDP) is a display panel that excites phosphors by vacuum ultraviolet rays caused by gas discharge occurring in a discharge cell to implement an image.

These PDPs are fixed to the chassis base on which a plurality of driving circuit boards are mounted, and the front cabinet and the back cover are located at the front and the rear of the PDP and the chassis base, respectively, and surround the PDP and the chassis base. The cover is integrally assembled to constitute a plasma display device.

In the above-described plasma display device, an electrode, especially an address electrode, formed inside the PDP is electrically connected to the corresponding driving circuit through a connecting member, which is typically a flexible printed circuit (FPC). Integrated circuits (ICs) are mounted on the integrated circuits.

As such, the voltage application structure using the FPC and the IC is largely referred to as a chip on board (COB) depending on the presence or absence of a printed circuit board (PCB). And chip on film (hereinafter referred to as 'COF'). Among these, COB refers to the IC mounted on the PCB, and COF refers to the IC directly mounted on the film (for example, polyimide film) constituting the FPC, not the PCB. Because of the simple structure and low price, it is widely used.

The COF typically surrounds the bottom of the chassis base such that one end is connected to the address electrode and the other end is connected to the drive circuit board mounted to the rear of the chassis base, and a portion thereof is fixed to the rear of the chassis base to prevent positional changes. do.

In particular, when the COF is mounted on a high-quality plasma display device driven by a single scan method and performs a function of applying a voltage, the COF is compared with a plasma display device driven by a dual scan method. About four times more heat is generated in the driver IC.

In addition, in order to express more than 256 gray levels in the PDP, at least eight address discharges must be performed for 1/60 seconds corresponding to one TV field, so that more heat is generated in the COF fixed to the chassis base. Therefore, the COF may not properly perform address signal processing due to the heat generated in the COF, resulting in screen distortion or a problem in that the screen quality is degraded. Furthermore, since the heat generation amount in COF varies from 0.5W to 10W for each IC, a heat dissipation structure is essential to secure device reliability of the COF.

Looking at the conventional COF heat dissipation technology, by applying the algorithm in the direction of less heat generated in the IC mounted on the FPC to lower the calorific value of the COF itself without dissipating the heat generated from the COF, and COF aluminum plate and A method of attaching the same heat conducting medium and attaching a heat sink to it to release heat of COF into the air is known.

Among the two methods described above, the former method causes a deterioration in image quality, and in particular, when the former method is applied to a high-definition PDP, a resolution that is actually seen by the eye may be deteriorated compared to a standard-class PDP screen. The latter method uses only convection to dissipate the COF heat into the air. Therefore, the degree of heat dissipation is weak, which can cause the COF to malfunction when the PDP is actually driven. There is a problem that the screen quality is degraded.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a cooling device capable of efficiently dissipating heat generated from a connecting member such as COF, thereby preventing malfunction of the IC mounted on the FPC. In addition, the present invention provides a plasma display device capable of stably processing signal of a driving circuit to reproduce a high quality screen.

In order to achieve the above object, the present invention,

A plasma display panel, a chassis base supporting a plasma display panel and mounting a plurality of driving circuit boards, a connecting member electrically connecting the plasma display panel and the driving circuit board, and fixedly connected to the chassis base together with the connecting member. And a cooling device for cooling the member, wherein the cooling device includes a first heat dissipation unit including a plurality of heat dissipation ribs, and a plurality of heat dissipation plates for heat dissipation, which are installed at a predetermined distance from the first heat dissipation unit. The present invention provides a plasma display device including a second heat dissipation unit, and at least one heat pipe that mechanically connects the first heat dissipation unit and the second heat dissipation unit to serve as a heat conduction medium between the first and second heat dissipation units.

The connection member is a chip on film (COF) having a flexible printed circuit and an integrated circuit mounted on the flexible printed circuit and applying a voltage to a plasma display panel according to a control signal of a driving circuit board. In this case, the heat dissipation sheet is attached to one surface of the flexible printed circuit in which the integrated circuit is mounted.

The heat dissipation plates of the second heat dissipation part are positioned side by side with the chassis base surface, and are continuously installed in the heat pipes at random intervals toward the rear of the chassis base. To this end, the heat pipe includes a vertical portion parallel to the chassis base surface and having an end fixed to the first heat dissipation portion, and a horizontal portion bent from the vertical portion and fixed in a line through the heat dissipation portions of the second heat dissipation portion.

In addition, the heat dissipation plates of the second heat dissipation unit may be disposed to be orthogonal to the chassis base surface, and may be disposed at arbitrary intervals from each other along the long axis direction of the chassis base. At this time, the second heat dissipation part may further include a support part integrally connecting the ends of the heat dissipation plates to allow the heat dissipation plates to function as heat dissipation ribs.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partial perspective view of a plasma display device having a chip on film provided with a cooling device according to an embodiment of the present invention, Figure 2 is a partial plan view of FIG.

Referring to the drawings, a connection member 6 for electrically connecting an electrode (not shown) inside the panel 30 and the driving circuit board 34 is provided, and the cooling device 12 outside the connection member 6. Is padded and provided. The connecting member 6 is made of, for example, a chip-on film in which an integrated circuit (hereinafter referred to as "IC") 2 is mounted directly on one surface of a flexible printed circuit (hereinafter referred to as "FPC") 4. In the following, a case in which the connecting member 6 is a chip on film will be described as an example.

Here, the front surface of the COF 6 in which the IC 2 is mounted faces the chassis base 10, and the rear surface of the COF 6 in which the IC 2 is not mounted faces the cooling device 12 so as to face the cooling device 12. 12) is attached. And it is preferable that the heat radiation sheet 38 is attached to the front surface of the COF 6 in which the IC 2 was mounted. The heat dissipation sheet 38 is made of, for example, a metal sheet such as aluminum or a silicon sheet, and may be fixed to the front surface of the COF 6 using an adhesive.

The cooling device 12 according to the present embodiment is largely fixed to the chassis base 10 and serves as a support plate of the cooling device 12, and a plurality of protrusions protruding from the base 14 toward the rear surface of the plasma display device. A first heat dissipation unit 18 having a heat dissipation rib 16, and a second heat dissipation plate 20 provided at a predetermined interval from the first heat dissipation unit 18 and having a plurality of heat dissipation plates 20 for heat dissipation. At least one heat pipe 24 serving as a heat conduction medium between the first and second heat dissipating portions 18 and 22 while mechanically connecting the heat dissipating portion 22 and the first and second heat dissipating portions 18 and 22. ).

The base 14 may be screwed to, for example, a boss 26 protruding from the chassis base 10. For this purpose, a screw hole is formed in parallel with the boss 26 and the base 14 corresponding to the boss 26, and the screw 28 is fastened to the screw hole to penetrate the base 14 and the boss 26. As a result, the cooling device 12 is firmly fixed to the rear surface of the chassis base 10.

When the cooling device 12 is fixed to the chassis base 10 through the boss 26 as described above, the COF 6, which is a main heating part of the plasma display device, does not come into contact with the chassis base 10 and the chassis base 10 does not come into contact with the chassis base 10. Mounted at regular intervals to minimize the effect of heat generated in panel 30 or chassis base 10 on COF 6. In addition, the heat generated from the COF 6 is partially discharged through the space between the chassis base 10 and the COF 6 to lower the temperature of the COF 6.

In addition, the first heat dissipation unit 18 constitutes a plurality of heat dissipation ribs 16 protruding from the base 14 at arbitrary intervals from each other, so that the contact area with the ambient air having a lower temperature than the COF 6 is relatively low. Maximize. As a result, the first heat dissipation unit 18 receives heat generated from the COF 6 and efficiently discharges it, and primarily radiates heat generated from the COF 6.

At this time, a hole 32 having an arbitrary size for fixing the heat pipe 24 is provided on the upper side surface of the first heat dissipation unit 18, and one end of the heat pipe 24 is inserted into and fixed to the hole 32. . The heat pipe 24 is made of a material having excellent thermal conductivity, for example, copper, stainless steel, tungsten, or the like, and serves to conduct heat from the first heat dissipation unit 18 to the second heat dissipation unit 22.

As described above, the first heat dissipation unit 18 emits a part of the heat emitted from the COF 6 into the air, and the heat released is retained around the first heat dissipation unit 18, so that the heat dissipation of the first heat dissipation unit 18 is reduced. There are certain limits to the function. Therefore, the heat pipe 24 conducts heat from the first heat dissipation unit 18 to the second heat dissipation unit 22 so that the second heat dissipation unit 22 complements the function of the first heat dissipation unit 18. In general, in the heat dissipation of an object, the conduction action is more effective in performing the heat dissipation function than the convection action, and the heat pipe 24 performs the function.

In the present embodiment, the heat pipe 24 has a shape of a “??” bent at approximately right angles, and has a vertical portion 24a parallel to the surface of the chassis base 10 and an arbitrary radius of curvature from the vertical portion 24a. It may be divided into a horizontal portion 24b bent at approximately 90 °, the end of the vertical portion 24a is fixed to the first heat dissipation portion 18, and the second heat dissipation portion 22 is installed on the horizontal portion 24b. do.

For reference, reference numeral 36 in FIG. 1 denotes an adapter for connecting the end of the COF 6 to the driving circuit board 34.

FIG. 3 is a partial front view of the cooling apparatus shown in FIG. 1, with reference to FIGS. 1 and 3 to describe the configuration of the heat pipe and the second heat dissipation unit. FIG.

In the present embodiment, the second heat dissipation part 22 has a configuration in which a plurality of heat dissipation plates 20 parallel to the chassis base surface are combined in a line, and is arranged on a horizontal portion 24b of the heat pipe 24 provided as a pair. The heat dissipation plates 20 may be installed side by side at arbitrary intervals to constitute the second heat dissipation unit 22.

As a result, the second heat dissipation unit 22 conducts heat from the heat pipe 24 to discharge heat through the heat dissipation plates 20 (see solid arrows in FIG. 3), and relatively cool air at the bottom of the second heat dissipation unit 22. Is introduced between the heat sinks 20 (see the dashed arrows in FIG. 3) to perform heat radiation by convection.

As described above, the cooling device 12 according to the present embodiment primarily dissipates heat generated by the COF 6 through the convection action of the first heat dissipation unit 18, and the heat pipe 24 is the first heat dissipation unit. The heat of 18 is conducted to the second heat dissipating portion 22, and the second heat dissipating portion 22 dissipates heat of the COF 6 secondly through convection. Therefore, the cooling device 12 according to the present embodiment exerts an excellent cooling function through a two-stage heat dissipation action to effectively reduce the heat of the COF (6).

Next, modifications of the embodiment of the present invention will be described with reference to FIGS. 4 to 6.

4 is a first variant, in which case the heat pipe 24 'is bent twice at approximately 90 ° with an arbitrary radius of curvature, based on the structure of the above-described embodiment, to form a cooling device. That is, in this modification, the heat pipe 24 'is formed from the first vertical portion 24a parallel to the chassis base surface, the horizontal portion 24b bent from the first vertical portion 24a, and the horizontal portion 24b. First and second fixing bars 40a extending vertically from the second vertical portion 24c toward the front and the rear of the plasma display device. , 40b).

Some of the heat dissipation plates 20 constituting the second heat dissipation part 22 are installed in the first fixing bar 40a at random intervals from each other, and the remaining heat dissipation plates 20 are at random intervals from each other. It is installed on the second fixing bar 40b to constitute the second heat dissipation part 22.

FIG. 5 is a second modification, in which case the heat sinks 20 'of the second heat dissipation part 22' are arranged so as to be orthogonal to the surface of the chassis base 10, based on the structure of the above-described embodiment. It is provided continuously in the heat pipe 24 at arbitrary intervals mutually along the major axis direction (x direction of drawing) of 10), and comprises the cooling apparatus 12. FIG.

At this time, the heat pipe 24 is formed in parallel with the chassis base surface and is fixed to the first heat dissipation portion 18, and the horizontal portion 24b bent at approximately 90 degrees from the vertical portion 24a. ), And a fixed bar 46 that connects across the pair of horizontal portions 24b, and the heat sinks 20 'are installed side by side at an arbitrary distance from each other on the fixed bar 46 so as to have a second heat dissipation. The part 22 'is comprised.

FIG. 6 is a third modification, in which case the second heat dissipation portion 22 "further comprises a support portion 42 which integrally connects the ends of the heat dissipation plates 20 ', based on the structure of the second modification described above. Thus, the heat sinks 20 'of the second heat dissipation part 22 "function as heat dissipation ribs, and the second heat dissipation part 22" has the same configuration as the first heat dissipation part 18.

The heat pipe 24 ′ is bent twice at approximately 90 ° with an arbitrary radius of curvature, as in the first variant described above, and is parallel to the chassis base surface to form the first vertical portion 24a and the first vertical portion 24a. And a second vertical portion 24c bent from the horizontal portion 24b, and the first vertical portion 24a is fixed to the first heat dissipation portion 18. 2 The vertical portion 24c is fixed to the second heat dissipation portion 22 ". At this time, a hole of an arbitrary size (not shown) is provided in the bottom surface of the support 42 of the second heat dissipation portion 22". The second vertical portion 24c of the heat pipe 24 'is inserted and fixed.

In the above-described embodiments and modifications, only the case where the connection member is a COF has been described, but the connection member may be mounted in various ways such as a chip on board (COB) and a tape carrier package (TCP) in addition to the COF. The structure is applicable.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the range of.

As described above, according to the present invention, the cooling device forcibly dissipates and dissipates heat generated in the connection member, thereby effectively dissipating heat of the connection member, in particular, the integrated circuit mounted on the connection member. As a result, the plasma display device according to the present invention has an effect of stabilizing signal processing in the driving circuit, preventing malfunction of the integrated circuit, and reproducing a high quality screen.

1 is a partial perspective view of a plasma display device having a chip on film provided with a cooling device according to an embodiment of the present invention.

2 is a partial plan view of FIG. 1.

3 is a partial front view of the cooling device shown in FIG. 1.

4 is a partial front view of a cooling device for explaining the first modification to the embodiment of the present invention.

5 and 6 are perspective views of a cooling device for explaining the second and third modified examples of the embodiment of the present invention, respectively.

Claims (12)

A plasma display panel; A chassis base supporting the plasma display panel and mounting a plurality of driving circuit boards; A connection member electrically connecting the plasma display panel and a driving circuit board; And A cooling device fixed to the chassis base together with the connecting member to cool the connecting member, The cooling device, A first heat dissipation unit having a plurality of heat dissipation ribs; A second heat dissipation unit installed at a predetermined distance from the first heat dissipation unit and having a plurality of heat dissipation plates for heat dissipation; And And at least one heat pipe serving as a heat conducting medium between the first and second heat dissipating parts while mechanically connecting the first and second heat dissipating parts. The method of claim 1, The connection member is a chip on film (COF) having a flexible printed circuit and an integrated circuit mounted on the flexible printed circuit and applying a voltage into the plasma display panel according to a control signal of a driving circuit board. Plasma display device. The method of claim 2, And a heat dissipation sheet attached to one surface of the flexible printed circuit in which the integrated circuit is mounted. The method of claim 1, The cooling device further comprises a base fixed to the rear of the chassis base to serve as a support plate of the cooling device, the base is screwed to the boss installed on the rear of the chassis base. The method of claim 1, And the heat pipe is made of any one of copper, stainless steel, and tungsten. The method of claim 1, The heat dissipation plates of the second heat dissipation part are disposed in parallel with the chassis base surface, and are continuously installed on the heat pipes at random intervals toward the rear of the chassis base. The method of claim 6, A plasma display including a vertical portion parallel to the chassis base surface and fixed to the first heat dissipation portion, and a horizontal portion bent from the vertical portion and fixed in a row through the heat dissipation portions of the second heat dissipation portion; Device. The method of claim 6, The heat pipe is parallel to the chassis base surface and has a first vertical portion whose end is fixed to the first heat dissipating portion, a horizontal portion bent from the first vertical portion, and a horizontal portion bent parallel to the first vertical portion And second and second fixing bars extending from the second vertical portion to the front and the rear of the chassis base to fix the heat sinks of the second heat dissipation portion. The method of claim 1, The heat dissipation plates of the second heat dissipation unit are disposed to be orthogonal to the surface of the chassis base, and are disposed at random intervals along the long axis direction of the chassis base. The method of claim 9, The heat pipe includes a vertical portion formed in parallel with the chassis base surface and fixed to the first heat dissipation portion, a horizontal portion bent from the vertical portion, and a fixing bar connecting the horizontal portions adjacent to each other. Plasma display device that the heat dissipation plate of the second heat dissipation member is installed in the fixing bar. The method of claim 9, And the second heat dissipation unit further includes a support unit integrally connecting end portions of the heat dissipation plates, wherein the heat dissipation plates function as heat dissipation ribs. The method of claim 9, The heat pipe is parallel to the chassis base surface and has a first vertical portion whose end is fixed to the first heat dissipating portion, a horizontal portion bent from the first vertical portion, and a horizontal portion bent parallel to the first vertical portion And a second vertical portion which is formed and is fixed to a support of the second heat dissipation portion.