JP2009075490A - Flat panel display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat display device having enhanced display-panel cooling performance, having good image quality performance and high reliability. <P>SOLUTION: The flat display device 1 has a structure that a chassis member 5 holding a plasma display panel 3 and having a heat radiation function, and the plasma display panel 3 are bonded together with a plurality of strip-like thermally conductive adhesive members 6 arranged discretely, and that the air flows through each gap part between the thermally conductive adhesive members 6 arranged discretely. Regarding the plurality of strip-like adhesive members 6, both the tip parts in the air flowing direction thereof are formed in a semicircular arc shape or a tapered shape, and the adhesive members are applied so as to form the air ventilation paths. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a flat panel display device, and relates to a cooling technique for heat generation of a display panel.

  In recent years, display devices have promoted the widespread use of thin, large-screen products with the progress of digital technology. As a typical product of this large screen display device, there is a flat display device using a self-luminous plasma display panel (hereinafter referred to as PDP). Since a display device with a large screen is required to display a high-definition image, the number of pixels is increased, and the amount of light emitted from the light-emitting element is increased in order to extract the luminance of the image. Based on these backgrounds, the PDP has caused a temperature rise. On the other hand, an increase in the temperature of the PDP changes the light emission luminance of the phosphor, which causes image quality degradation. Furthermore, depending on the information displayed, a situation where the brightness is high only in a part of the screen may occur, and if the temperature rise due to the discharge of the PDP is concentrated in a small area, the glass substrate constituting the PDP is damaged. There is also.

  Therefore, in the development of the plasma display device, cooling of the PDP is an indispensable problem, and conventionally, many cooling techniques have been proposed in relation to the heat dissipation method using the chassis member.

  In a plasma display device, in order to provide a chassis that exhibits sufficient heat dissipation and is suitable for cooling a plasma display panel, a chassis in which a hollow portion is formed by heat radiation fins provided on an aluminum plate is interposed between a PDP and a drive circuit. A technique for disposing is disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 11-233968).

  In addition, there is a method of using a heat conductive adhesive to improve workability in the thermal connection between the PDP and the holding plate, but the ease of separation between the panel and the holding plate when recycling the plasma display device. For this purpose, the heat conductive member is arranged with a predetermined interval, is composed of a stretch-peeled strip-shaped heat conductive adhesive, and the technology that sets the thickness and arrangement relationship of the heat conductive adhesive is patented It is disclosed in Document 2 (Japanese Patent Laid-Open No. 2005-208190).

  Similarly, for the purpose of facilitating the separation of the panel and the holding plate, the heat conductive member is constituted by a stretch-peeled strip-shaped adhesive, and the technology for identifying the shape of the strip-shaped adhesive is This is disclosed in Patent Document 3 (Japanese Patent Application Laid-Open No. 2004-309549).

Japanese Patent Laid-Open No. 11-233968 JP 2005-208190 A JP 2004-309549 A

  However, the conventional techniques as described above have technical problems that need to be solved.

  The chassis of the plasma display device described in Patent Literature 1 has a function or function of further improving the heat dissipation of the chassis, with the hollow portion formed by the fins for heat dissipation serving as a wind passage (

). However, the formation of the hollow portion serving as the air passage is configured by brazing the heat radiating fins to the aluminum plate, which leads to the complexity of the manufacturability of the chassis and high cost. In addition, the size of the plasma display device is increased, which is an obstacle to downsizing the plasma display device.

  In the plasma display device described in Patent Document 2, the thermal connection between the panel and the holding plate is performed by applying a heat conductive adhesive at a predetermined interval and thermally connected. Cost reduction due to the reduction of heat connection members can be expected. It can also be easily separated at the time of disposal (

). However, no consideration has been given to the improvement of the original heat conduction performance of the heat conductive adhesive, and the arrangement and shape of the heat conductive members are not subject to deterioration of image quality. It is set only for material reduction and ease of separation.

  Similarly to the content described in Patent Document 2, the plasma display device described in Patent Document 3 is also thermally connected by applying a heat conductive adhesive at a predetermined interval when thermally connecting the panel and the holding plate. Therefore, a significant improvement in workability and cost reduction due to a reduction in heat connecting members can be expected. Furthermore, in order to perform separation at the time of disposal more easily, a device is devised for the application shape of the heat conductive adhesive. However, as in Patent Document 2, no consideration has been given to the improvement of the original heat conduction performance in the heat conductive adhesive, and the arrangement and shape of the heat conductive members are reduced in the material of the adhesive and the separation. It is only set for ease.

  The object of the present invention is to improve the image quality performance by improving the cooling performance by heat dissipation by causing the heat generated in the display panel to transfer heat through the heat-conductive adhesive member and passing the air through the gap between the adhesive members. It is to provide a high flat display device.

  In order to solve the above problems, a flat display device using a plasma display panel according to the present invention includes a chassis member that holds the plasma display panel and has a heat dissipation function, and the plasma display panel and the chassis member have a plurality of strip shapes. A flat display device having a structure in which air is passed through gaps between thermally conductive adhesive members that are discretely arranged and bonded by discretely arranged heat conductive adhesive members. This strip-shaped adhesive member has a configuration in which the shape of both end portions in the direction of air flow is applied as a semicircular arc or a tapered shape.

  Furthermore, the plurality of strip-shaped adhesive members are arranged and applied in a staggered manner.

  In addition, with this configuration, the air flow path formed by the gap portion of the adhesive member has a substantially uniform cross-sectional shape of the flow path section at the flow path sections at both ends excluding the air flow inlet and the air flow outlet. Thus, it is formed by applying an adhesive member.

  Furthermore, the air flow path formed by the gap between the adhesive members is different from the air flow path from the air flow inlet to the air flow outlet so that the air flow is different between the central part and the peripheral part of the plasma display panel. The cooling performance is further optimized by applying and forming the adhesive member so that the sum of the adjacent channel cross-sectional shapes becomes substantially equal.

  According to the present invention, it is possible to improve the cooling performance of the display panel by the air flowing through the gap between the adhesive members, to realize a flat display device with good image quality and high reliability.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram schematically showing a flat display device according to the present invention. The flat display device 1 has a self-luminous PDP 3 in a housing 2, and circuit components for operating and driving the flat display device 1 are mounted on the back side of the PDP 3 in the housing 2. A circuit board 4 is disposed, and the circuit board 4 is held by a chassis member 5 on a surface opposite to the PDP 3 by a holding member (not shown).

  Here, the PDP 3 includes a light emitting element portion 31 that emits ultraviolet rays by discharge and irradiates a phosphor to emit light, and a front side glass substrate 32 and a back side glass substrate 33 that sandwich it from the front and rear. Yes. Heat generated by the light emitting element portion 31 is transferred to the glass substrates 32 and 33 on both sides.

  Further, the PDP 3 is bonded and held to the chassis member 5 exhibiting a heat radiation function by a material having good heat conduction characteristics by an adhesive member 6 having good heat conductivity. Therefore, part of the heat generated by the PDP 3 is transferred to the chassis member 5 through the adhesive member 6 and is radiated from the chassis member 5.

  A part of the heat generated by the PDP 3 is radiated by heat transfer to the air passing through the gap space formed by the adhesive member 6.

  FIG. 1 shows a basic example of the application shape of the adhesive member 6 in the present invention. For the convenience of explaining the application shape of the adhesive member 6, a part of the PDP 3 is removed.

  In the flat display device 1 of the present invention, the adhesive between the PDP 3 and the chassis member 5 is not adhered to the entire surface by the adhesive member 6, but the adhesive members 6 are discretely arranged in a strip shape with a predetermined interval. And have a structure of bonding.

  Moreover, the adhesive member 6 applies an adhesive (for example, a hot-melt adhesive) that has fluidity at high temperatures. A hot-melt adhesive is a highly heat-conductive adhesive, which is heated to a high temperature and applied as a fluidized state, and then solidified at a low temperature to maintain the adhesive force. The application shape of the adhesive member 6 shown in the drawing is for explaining the concept, and does not specify the size or number of the strip-like adhesive member 6 with respect to the shape of the PDP 3.

  Next, the cooling performance in the application structure of the adhesive member 6 will be described. The application shape of the adhesive member 6 is a strip shape with a predetermined width (W), and is applied in a stripe shape from the lower end portion to the upper end portion of the PDP 3 with a gap (P). One of the conditions for determining the application width (W), the interval (P), and the application thickness (T) of the adhesive member 6 is to obtain the adhesion holding strength between the PDP 3 and the chassis member 5. Needless to say, the merit of discretely applying the adhesive member 6 in a strip shape is about cost reduction by reducing the amount of adhesive applied as in the prior art, and ease of disassembly at the time of disposal, An aspect of the present invention is to improve the cooling action by the flow of air in the gap space formed by discrete application of the adhesive member 6.

  The gap space is formed as a flow path (cross-sectional area P × T) by a side wall having a coating thickness (T) of the adhesive member 6 adjacent to each other with a gap (P). In order to maintain adhesive strength, the coating thickness (T) is about 1 mm, so that it is configured as a gap space through which air can flow.

  The gap space of the adhesive member 6 has a hollow structure that allows ventilation by natural convection with the lower end side as an air inflow port and the upper end side as an air outflow port as shown by the white arrow in FIG. . The air inlet of the adhesive member 6 applied in a strip shape and the tip located at the air outlet are formed by a substantially semicircular arc with a predetermined curvature so that air can smoothly flow in and out. Is formed. The shape of the tip may be a tapered linear shape instead of an arc shape.

  The heat generated by the PDP 3 is preferably transferred to the air passing through the gap space to dissipate the heat, so that it is desirable to increase the amount of heat transferred by the air. Here, the heat transfer from the PDP 3 to the air is determined by the surface shape of the PDP 3, the ventilation pressure of the air, the flow velocity of the air, etc., and therefore it is preferable to forcibly blow by an unillustrated air blowing mechanism (such as a pump). is there. The heat transfer coefficient can be increased by about 10 times by forced ventilation with respect to the heat transfer coefficient in natural convection. The cross-sectional area of the flow path by the gap is the flow path excluding the tip of the air inlet and the air outlet in order to allow the air to flow smoothly when forced air is sent to the gap space by a delivery mechanism such as a pump. In the part, it is comprised substantially equally. As described above, in the configuration that enables smooth ventilation of air, an effect of lowering the heat generation temperature of the PDP 3 by about 10 ° C. can be seen by setting the flow rate of ventilation to about 0.3 m / sec.

  FIG. 2 is a conceptual diagram showing a second embodiment relating to the application shape of the adhesive member in the present invention. The application shape of the strip-shaped adhesive member 6 (61, 62) is not a continuous stripe shape from the lower end side to the upper end side of the PDP 3, but an intermittent shape. In FIG. 2, although it divides | segments into two, the number of division | segmentation is not limited. Further, the tip of the divided strip-shaped adhesive member 6 is configured as a semicircular arc or a tapered shape as in the first embodiment.

  When cooling is performed by transferring heat to the air flowing through the heat generated by the PDP 3, when the air is excessively transferred to the lower end of the gap space and the temperature rises, regardless of the air flow rate to the upper end, There is a concern that heat transfer at the upper end may be impaired. Since the adhesive member 6 is intermittently divided and applied in the vertical direction of the PDP 3 and has a gap penetrating the left and right ends, the inflow and outflow of air in the left and right direction is enabled, and the temperature of the ventilation air is increased. It is possible to suppress and improve the cooling performance.

Furthermore, as shown in FIG. Arrangement of the strip-like adhesive members 6 to be applied discretely is staggered with respect to each other. The air that flows through the gap space as the flow path is applied in a zigzag manner on the upper end side, as indicated by the white arrow in the figure. Separated in the flow path formed by the adhesive member 62 and mixed with the air in the adjacent flow path on the lower end side, the air flows from the flow path on the lower end side of the PDP to the flow path on the upper end side. The tips of the pressure-sensitive adhesive members 61 and 62 have a substantially semicircular arc or a tapered shape, so that the application of the pressure-sensitive adhesive member 6 is divided and arranged in a zigzag pattern, And mixing can be performed smoothly. The purpose of air splitting and mixing is to increase the cooling effect by averaging the temperature of the air that rises due to heat transfer even when the PDP 3 generates a partial heat generation state based on the display information. It is. Therefore, increasing the number of intermittent divisions of the pressure-sensitive adhesive member 6 is more preferable because it allows air to be mixed in a plurality of flow paths and can be more averaged.
Moreover, in order to perform air diversion, mixing, and air ventilation more smoothly, the sum of the cross-sectional areas with adjacent flow paths is configured to be approximately equal from the lower end portion to the upper end portion of the PDP 3, It is preferable to suppress the flow resistance during ventilation.

  FIG. 3 is a conceptual diagram showing a third embodiment relating to the application shape of the adhesive member in the present invention. The embodiment shown in FIG. 3 is similar to the second embodiment in the application shape of the adhesive members 6 that are intermittently divided and arranged in a staggered manner, and further in the lateral direction of the PDP 3. The gap space formed by is applied in a different state in the inner part and the outer part of the PDP 3. That is, P1 of the interval PDP3 formed on the inner side of the PDP3 is wider than the interval P2 formed on the outer side (P2> P1). That is, the cross-sectional area of the air passage on the inner side is larger than the cross-sectional area of the air passage on the outer side of the PDP 3. The air blown through the flow path formed by the adhesive member 61b applied to the lower end side is diverted, mixed and ventilated toward the flow path formed by the adhesive member 62b applied to the upper end side. Also here, as in the second embodiment, in order to ensure smooth ventilation, the tip of the adhesive member 6 divided and applied in the vertical direction is constituted by a substantially semicircular arc or a tapered shape. Has been.

  In addition, the shape of the flow path formed on the upper end side is applied as an interval P3 (for example, (P1 + P2) / 2) substantially equal to the sum of the cross-sectional areas of the adjacent flow paths on the lower end side to form a gap space. With these configurations, it is possible to further average the cooling effect in the inner portion where an increase in the amount of heat generated by the display information is likely to be stored.

  In the above embodiment, as shown in FIG. 1, the chassis member 5 and the circuit board 4 are separated from each other, and the structure in which the influence of the heat generated on the circuit board 4 on the PDP 3 is suppressed is described. However, the present invention is not limited to this structure, and is particularly applicable to a structure in which the chassis member 5 and the circuit board 4 are in contact with each other, or a structure in which the electrode driving circuit is directly attached to the chassis member 5. That is, the gap space formed by the adhesive member 6 in the chassis member 5 side region corresponding to the electrode drive circuit portion of the circuit board 5 is configured to be wider than other regions. With this configuration, it is possible to increase the air volume in a region corresponding to the electrode drive circuit unit, and to suppress the influence of heat generated by the electrode drive circuit unit on the PDP 3.

  With the configuration in which air is passed through the gap space formed by the PDP 3 and the chassis member 5 joined by the adhesive member 6 as described above, the heat generated by the PDP 3 is directly transferred to the air to dissipate the heat, and the heat generated by the PDP 3 is also reduced. By transferring heat to the chassis member 5 through the highly heat-conductive adhesive member 6 and cooling with air from both sides of the chassis member 5, the cooling efficiency can be improved. Further, it is possible to average the temperature rise in the entire screen and realize a good image quality.

  Furthermore, the discrete application of the adhesive member 6 makes it possible to improve the workability of joining the PDP 3 and the chassis member 5 and reduce the cost.

It is the schematic block diagram which showed typically the flat type display apparatus in this invention. It is a conceptual diagram which shows the 2nd Example regarding the application | coating shape of the adhesion member in this invention. It is a conceptual diagram which shows the 3rd Example regarding the application | coating shape of the adhesive member in this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Flat panel display device, 2 ... Housing | casing, 3 ... Plasma display panel, 4 ... Circuit board, 5 ... Chassis member, 6 ... Adhesive member.

Claims (5)

In a flat display device using a plasma display panel,
A chassis member that holds the plasma display panel and has a heat dissipation function,
The plasma display panel and the chassis member are joined by a plurality of strip-shaped, thermally conductive adhesive members that are discretely arranged, and in a gap between the discretely arranged thermally conductive adhesive members. A flat-type display device having a structure through which air flows,
The flat display device, wherein the plurality of strip-shaped adhesive members are applied as semicircular arcs or tapered shapes at both ends in a direction in which air flows. The flat display device according to claim 1,
The flat display device, wherein the plurality of strip-shaped adhesive members are arranged and applied in a staggered manner. The flat display device according to claim 1 or 2,
The air passage formed by the gap portion of the adhesive member has an air inlet and an air outlet except for the tip portion of the air outlet so that the cross-sectional shape of the channel portion is substantially uniform. A flat display device characterized in that it is formed by coating. The flat display device according to claim 1 or 2,
The air flow path formed by the gap between the adhesive members is configured such that the flow rate of the flow path part from the air inlet to the air outlet is different from the air flow rate at the central part and the peripheral part of the plasma display panel, A flat display device characterized in that it is formed by applying the adhesive member so that the sum of the cross-sectional shapes of adjacent flow path portions is substantially uniform. The flat display device according to claim 4,
2. A flat panel display according to claim 1, wherein a cross-sectional area of the air passage in the central portion is larger than a cross-sectional area of the air passage in the peripheral portion.

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