This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2006-042305, filed on Feb. 20, 2006, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a plasma display device in which a plasma display panel is mounted.
2. Description of the Related Art
A plasma display device is constructed by accommodating a plasma display panel module (PDP module) in a case. The PDP module is constituted of a plasma display panel (hereinafter, also referred to as PDP), a base chassis supporting the PDP, and a circuit board for driving the PDP. The PDP module is fixed to the case in a predetermined position by fixing the base chassis to installation parts in the case. A front surface of the case has an opening part at a position facing an image display surface of the PDP. The PDP is mainly made of glass, and weak to impact such as an external force. Accordingly, protection glass for protecting the PDP is attached to the opening part.
Japanese Unexamined Patent Application Publication No. 2001-324942 discloses a base chassis having a structure to disperse stress for alleviating impact applied to the PDP from a rear surface of the case. Japanese Unexamined Patent Application Publication No. 2004-069888 discloses a technique to form installation parts on a periphery of a base chassis for fixing the base chassis to the case. Japanese Unexamined Patent Application Publication No. 2005-115381 discloses a technique to fix a base chassis to a case by installation members arranged on four corners of the base chassis.
In recent years, in order to reduce the weight and cost of a plasma display device, there is proposed a plasma display device in which the protection glass on a front surface of the case is removed and the image display surface of the PDP is exposed directly via the opening part of the case. In this case, the display surface of the PDP receives impact such as an external force directly.
However, a conventional plasma display device with the display surface of the PDP protected by the protection glass does not have a structure to absorb an external force applied to the display surface. Therefore, when the PDP and the base chassis of the plasma display device without the protection glass is given stress by an external force (pushing force) applied to the display surface, the stress concentrates to a surrounding part of the PDP close to installation parts, and may cause breakage thereof.
An object of the present invention is to alleviate impact to a PDP when applied an external force from a front surface and a rear surface of a case, thereby preventing breakage of the PDP.
In a plasma display device according to the present invention, a base chassis has a chassis body in a plate form arranged on a rear surface of a plasma display panel and a plurality of projection parts provided to project from a periphery of the chassis body. A surrounding part of an image display surface of the plasma display panel is brought in contact with a contact part formed around an opening part of a front case. The projection parts of the base chassis are fixed to a chassis fixation part provided in the front case outside a periphery of the plasma display panel. A rear case is connected to the front case to cover the rear surface of the plasma display panel.
The rear case is not in contact with the plasma display panel. Accordingly, an external force applied from the rear case side is transmitted to the chassis fixation part only, preventing impact to the plasma display panel. The projection parts of the base chassis each have an elastic structure part which elastically deforms in response to a pushing force to the image display surface of the plasma display panel. Accordingly, also when the plasma display panel directly receives an external force from the front case side, the elastic structure part can elastically deform to alleviate the impact to the plasma display panel.
The nature, principle, and utility of the invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings in which like parts are designated by identical reference numbers, in which:
Hereinafter, embodiments of the present invention will be explained using drawings.
A plasma display panel module (PDP module) is formed of the PDP 100, the filter 200, the base chassis 500, the double-faced adhesive tapes 600, the reinforced plates 700 and the substrate board. Specifically, the plasma display device is constituted by accommodating the PDP module in the cases 300, 400.
As shown in
The front case 300 has an opening part 302 formed facing the display surface 102 of the PDP 100, and a surrounding edge part 304 projecting toward the rear case 400 side. On a periphery (edge part) of the opening part 302, a flat surface 306 in a frame form projecting on the display surface 102 side is formed. This flat surface 306 operates as a contact part to which a surrounding part of the display surface 102 contacts via the filter 200. The double-faced adhesive tapes 600 bonding the PDP 100 to the base chassis 500 are resin tapes for example and have elasticity. Accordingly, a part of impact applied to the PDP 100 from the front case 300 is absorbed by the double-faced adhesive tapes 600. For the double-faced adhesive tapes 600, ones having good heat conductivity are used. Accordingly, heat generated by the PDP 100 can be transmitted efficiently to the base chassis 500 and the reinforced plates 700. The rear case 400 has a surrounding edge part 402 projecting toward the front case 300 side. The rear case 400 covers the rear surface side of the PDP module, and the surrounding edge part 402 is connected to the surrounding edge part 304 of the front case 300.
The base chassis 500 has a substantially square shape, and has a chassis body 502 in a plate form facing the PDP 100, and projection parts 504 projecting respectively from four corners of the chassis body 502 outward (in a flat surface direction of the base chassis 500). The chassis body 502 and the projection parts 504 are formed of one member by, for example, pressing a plate material made of an aluminum alloy. Details of the projection parts 504 are explained with
The first bend part 504a is formed by bending a projection part 504 from the chassis body 502 toward the surrounding edge part 402 side of the rear case 400. The first extension part 504b is connected to the first bend part 504a and extends obliquely in a direction to depart from a center of the PDP 100 toward the rear case 400 side. The second bend part 504c is formed by bending an edge side of the first extension part 504b toward the PDP 100 side. The second extension part 504d is connected to the second bend part 504c and extends in a direction parallel to the display surface 102 of the PDP 100. The second extension part 504d has penetration holes 504e for allowing penetration of screws to fix the base chassis 500 to the front case 300.
A bend angle A1 of the extension part 504b relative to a flat surface of the PDP 100 is preferably 30 degrees or larger and smaller than 90 degrees. Accordingly, the projection part 504 can have a spring characteristic against a force applied in an orthogonal direction of the PDP 100. In other words, the first bend part 504a, the first extension part 504b and the second bend part 504c function as an elastic structure part 506 which elastically deforms in response to a pressing force applied to the display surface 102 of the PDP 100.
As shown in
The rear substrate 108 has address electrodes 122 formed in parallel to each other on the glass substrate 120. The address electrodes 122 are arranged in a direction perpendicular to the X electrodes 112, Y electrodes 114. The address electrodes 122 are covered by a dielectric layer 124. On the dielectric layer 124, barrier ribs 126 are formed at positions corresponding respectively to both sides of the address electrodes 122. The barrier ribs 126 partitions discharge cells in a row direction. Furthermore, on side faces of the barrier ribs 126 and on the dielectric layer 124 between the barrier ribs 126, there are applied phosphors 128, 130, 132 which emit visible lights of red (R), green (G), blue (B) when being activated by an ultraviolet ray.
The PDP 100 is constructed by attaching the front substrate 106 and the rear substrate 108 so that the protection layer 118 and the barrier ribs 126 come in contact with each other, and sealing discharge gas such as Ne, Xe, or the like. The respective electrodes 112, 114, 122 extend to ends of the PDP 100 located outside a seal area formed on an outer peripheral part of the PDP 100, and are connected to a driver circuit via a later-described flexible printed circuit or the like.
Eight driver modules 900 are arranged along each longer side of the base chassis 500. The driver modules 900 are fixed to the base chassis 500 using studs (bosses) having female screws. Details of the driver modules 900 are explained in later-described
The flexible printed circuit 910 has a connection part 912 connected to the address driver circuit 806 and a connection part 914 connected to the address electrodes 122 of the PDP 100. On both sides of the connection part 914 of the flexible printed circuit 910, ground lines GND are arranged, and on an area sandwiched between the ground lines GND, signal lines SIG connected to the address electrodes 122 are arranged. On the flexible printed circuit 910, a plurality of dummy lines DMY are arranged on a surface opposing the radiation plate 920. Heat generated by the driver IC is transmitted efficiently by the dummy lines DMY to the radiation plate 920.
The driver module 900 is attached to the base chassis 500 together with the reinforced plate 700 by inserting screws in the penetration holes 703, 922 and attaching these screws to bosses fixed on the base chassis 500. The radiation plate 920 of the driver module 900 is in close contact with the reinforced plate 700 in a pressed state by screwing. Accordingly, heat generated from the driver module 900 is transmitted efficiently to the reinforced plate 700 and dispersed from the reinforced plate 700.
The reinforced plates 700 are attached to the front case 300 together with the base chassis 500 by inserting screws in the penetration holes 703, 504e and attaching these screws to the front case 300. The reinforced plates 700 are in close contact with the second extension parts 504d of the base chassis 500 in a pushed state. Accordingly, a part of heat generated from the PDP 100 and conducted to the base chassis 500 is conducted further to the reinforced plates 700. In other words, the reinforced plates 700 can lower a surface temperature of the PDP 100.
Furthermore, the reinforced plates 700 can enhance rigidity of the base chassis 500. Especially, the reinforced plates 700 are arranged along a longer side of the base chassis 500, and are fixed to the base chassis 500 via not only the second extension parts 504d but also the radiation plates 920 of the driver modules 900. This can enhance rigidity against bending of the base chassis 500 with a shorter side direction thereof being an axis.
The PDP module (100, 200, 500, 600, 700) is installed on the front case 300 by fixing the projection parts 504 (second extension parts 504d) of the base chassis 500 and the reinforced plates 700 by screws SC2 to the chassis fixation part 308. In a state that the PDP module is installed on the front case 300, the display surface 102 of the PDP 100 abuts on the flat surface 306 in a frame form of the front case 300 via the filter 200. The rear case 400 is fixed by screws SC3 to the chassis fixation part 308 after the surrounding edge part 402 is placed outside the surrounding edge part 304 of the front case 300. Thus, the plasma display device is constructed. Note that the rear case 400 has penetration holes for allowing penetration of the screws SC3.
In this embodiment, the front case 300 and the rear case 400 are formed including resin or metal having electroconductivity. The filter 200 has a metal mesh or a transparent electrode attached on a surface thereof. Thus, in a state shown in
The base chassis 500 is not connected to the rear case 400. Accordingly, when impact (external force) is applied from the rear case 400 side toward the PDP 100, the impact is not transmitted to the PDP 100 but is absorbed by the chassis fixation part 308. Even when the impact is transmitted from the chassis fixation part 308 to the base chassis 500, the elastic structure parts 506 of the projection parts 504 elastically deform, so that transmission of the impact to the PDP 100 can be prevented.
On the other hand, when impact is applied from the front case 300 side toward the PDP 100, the PDP 100 receives the impact directly. However, the elastic structure part 506 elastically deforms by a pushing force received by the PDP 100, so that stress applied to the surrounding part of the PDP 100 by the impact can be alleviated. In other words, the impact applied to the PDP 100 is absorbed by the elastic structure parts 506. Thus, in the plasma display device having a structure such that the display surface of an image of the PDP 100 is exposed via the opening part 302 of the front case 300, impact resistance of the PDP 100 can be enhanced.
As above, in the first embodiment, since the projection parts 504 has the elastic structure parts 506, even when impact (external force) is applied to the PDP 100 from the display surface 102 side of an image, the stress applied to the PDP 100 can be alleviated due to elastic deformation of the elastic structure parts 506. Accordingly, particularly in a plasma display device which does not have a protection glass on the display surface 102 side, impact resistance from the front side can be enhanced, and thus breakage of the PDP 100 can be prevented.
The projection members 504A are formed by bending a plate material in a step form. Then, similarly to the projection part 504 in the first embodiment, the projection members 504A are each formed to have a first bend part 505a, a first extension part 505b, a second bend part 505c and a second extension part 505d. The first bend part 505a, the first extension part 505b, the second bend part 505c and the second extension part 505d have the same shapes as the first bend part 504a, the first extension part 504b, the second bend part 504c and the second extension part 504d in the first embodiment. The second extension part 505d has penetration holes 505e for allowing penetration of screws for fixing the base chassis 500A to the front case 300. The projection member 504A has penetration holes 505f for allowing penetration of screws for attaching the projection member 504A to the chassis body 502A.
Similarly to the first embodiment, bend lines of the bend parts 505a, 505c are formed substantially in parallel to a diagonal line DIA of the PDP 100 corresponding to a pair of adjacent projection members 504A. An angle A2 for the bend lines is 29 degrees in this example, and is preferably 25 degrees or larger and smaller than 90 degrees, due to the same reasons as in the first embodiment.
As above, also in the second embodiment, the same effects as in the first embodiment can be obtained. Furthermore, in this embodiment, by forming the base chassis 500A of the chassis body 502A and the projection members 504A, the base chassis 500A can be manufactured easily. Further, when a projection member 504A has a defect, it is just needed to replace the projection member 504A, which simplifies fixing.
Note that in the above-described embodiments, examples of forming the base chassis 500, 500A, the reinforced plates 700 and the radiation plates 920 of an aluminum alloy are explained. The present invention is not limited to such embodiments. For example, the base chassis 500, 500A, the reinforced plates 700 and the radiation plates 920 may be formed of an iron alloy. In this case, the cost of the plasma display device can be reduced.
In the above-described embodiments, an example of forming one reinforced plate 700 along a longer side direction of the PDP 100 is explained. The present invention is not limited to such embodiments. For example, as shown in
In the above-described embodiments, there are explained examples of forming the bend part 504a, the extension part 504b and the bend part 504c by bending the projection part 504 of the base chassis 500 twice in a step form, to thereby constitute the elastic structure 506 by these bend part 504a, extension part 504b and bend part 504c. The present invention is not limited to such embodiments. For example, as shown in
In the above-described embodiments, there are explained examples of arranging the reinforced plates 700, 700A along a longer side of the PDP 100. The present invention is not limited to such embodiments. For example, the reinforced plates may be arranged along a shorter side of the PDP 100 or along a longer side and a shorter side of the PDP 100 respectively. Furthermore, the reinforced plates may be arranged along a diagonal line DIA of the PDP 100.
The invention is not limited to the above embodiments and various modifications may be made without departing from the spirit and scope of the invention. Any improvement may be made in part or all of the components.
Number | Date | Country | Kind |
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2006-042305 | Feb 2006 | JP | national |
Number | Name | Date | Kind |
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5929950 | Matsuda | Jul 1999 | A |
6583843 | Ishino | Jun 2003 | B2 |
6813159 | Irie et al. | Nov 2004 | B2 |
6859357 | Morimoto et al. | Feb 2005 | B2 |
6972963 | Chou | Dec 2005 | B1 |
7321487 | Kim | Jan 2008 | B2 |
7372700 | Jeong | May 2008 | B2 |
7379128 | Tsubokura et al. | May 2008 | B2 |
7394186 | Kim | Jul 2008 | B2 |
20060061945 | Kim | Mar 2006 | A1 |
20060077620 | Kim | Apr 2006 | A1 |
Number | Date | Country |
---|---|---|
1230740 | Jun 1999 | CN |
1658256 | Aug 2005 | CN |
2001-324942 | Nov 2001 | JP |
2004-6888 | Mar 2004 | JP |
2004-069888 | Mar 2004 | JP |
2004-361615 | Dec 2004 | JP |
2005-115381 | Apr 2005 | JP |
Number | Date | Country | |
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20070195494 A1 | Aug 2007 | US |