KR20030069313A - EMI insulation system of flat CRT - Google Patents

Abstract

PURPOSE: An electromagnetic interference shielding structure is provided to achieve improved performance of electromagnetic wave shielding by maintaining the electrified state between the shielding film and conductive layer constant. CONSTITUTION: An electromagnetic interference shielding structure comprises a shielding film(24) including a contamination prevention layer(241), a conductive layer(242), a PET layer(243), an adhesive layer(244), and a protective film, wherein the shielding film is attached to a safety glass; and a reinforcement band(22) wrapping the edge of a panel(12), and which is grounded to the shielding film. The contamination prevention layer and the PET layer of the shielding film are partially removed, and the conductive layer is partially exposed. A conductive filler material(40) is applied on the exposed portion. A grounding tape(30) connected to the reinforcement band is connected to the conductive filler material, to thereby ground the shielding film and the reinforcement band.

Description

Electromagnetic shielding structure of flat cathode ray tube {EMI insulation system of flat CRT}

The present invention relates to a cathode ray tube, and more particularly, to an electromagnetic shielding structure of a planar cathode ray tube.

In general, the cathode ray tube is divided into a curved cathode ray tube and a planar cathode ray tube according to the shape of the image plane. The planar cathode ray tube is fused and bonded to the funnel 10 and the funnel 10 as shown in FIG. A flat panel 12 having a fluorescent film 121 and an electron gun 14 mounted in the funnel 12 to emit an electron beam toward the fluorescent film 121 and to deflect the electron beam emitted from the electron gun 14. It comprises a deflection yoke (15).

Here, a shadow mask 16 is provided on the inner surface side of the panel 12 to color-select the emitted electron beam to reach the fluorescent film 121. The shadow mask 16 is a rail attached to the panel 12. It is attached to the structure supported by (17).

The planar cathode ray tube reproduces an image in such a manner that the electron beam emitted from the electron gun 12 collides with the fluorescent film 121 to emit light.

On the other hand, since the inside of the cathode ray tube is in a high vacuum state so that the electron beam emitted from the electron gun 14 can reach the fluorescent film 121 well, the funnel 10 and the panel 12 have pressures inside and outside the cathode ray tube. Due to the difference, a pressure of about 1 atmosphere is applied.

Due to this pressure, the funnel 10 and the panel 12 are slightly deformed than the initial state, and are subjected to tensile stress due to the deformation. In this case, the tensile stress is as long as the structural strength of the cathode ray tube is weakened. By acting as a cause, the risk of explosion of the cathode ray tube increases when an external shock is applied.

Accordingly, the flat cathode ray tube is mounted on the surface of the panel 12 to prevent the panel 12 from being tensioned and to absorb the impact from the outside, and to surround the edge of the panel 12. Therefore, the reinforcement means such as the reinforcement band 22 to prevent the deformation of the panel is provided, thereby reducing the explosion risk.

In addition, in the cathode ray tube, a strong magnetic field is formed in a high voltage circuit such as a deflection yoke 15, a flyback transformer (not shown), and a switching coil such as a degaussing coil, thereby generating harmful electromagnetic waves. Harmful electromagnetic waves are emitted through the panel 12.

Thus, the electromagnetic wave emitted from the cathode ray tube causes problems such as VDT syndrome harmful to the human body or malfunctions of adjacent devices. Grounding film method used as one of the conductive film is attached to the surface of the safety glass 20, the shielding film 24 is made of a structure to ground with the reinforcing band 22.

Here, the shielding film 24 is a multi-layered structure as shown in Figure 2 as a pollution prevention layer 241 to prevent contamination or scratching, the conductive layer 242 made of a conductive material, PET for flexibility and form configuration of the film A layer 243, an adhesive layer 244 for adhering to the panel 12, and a protective film 245 for protecting the adhesive layer 244.

The shielding film 24 is attached in such a manner that the pressure-sensitive adhesive layer 244 is adhered to the outer surface of the panel 12 by applying pressure by using a pressure roller or the like after removing the protective film 245. After attaching to (12), the conductor layer 242 and the reinforcing band 22 are grounded. In this case, a so-called simple welding method and an ultrasonic welding method are used.

In the simple welding method, as shown in FIG. 3A, the shielding film 24 is attached to the safety glass 20, and then the grounding tape 30 made of aluminum is connected to the reinforcing band 22. In the ultrasonic welding method, an ultrasonic generator is used to drill a hole to the conductor layer 242 as shown in b of FIG. 3, and then insert the ground wire 32 connected to the reinforcing band 22 into the hole. By connecting the ground wire 32 and the conductor layer 242 by welding.

On the other hand, according to each of these grounding methods, various problems occur depending on their characteristics, which will be described below.

First, a simple welding method requires a special welding agent for welding the conductor layer 242 and the ground tape 30, and precisely controls the welding temperature and time so that the shielding film 24 is not damaged or deformed during the welding process. As the uneven part is formed by welding, the coupling state between the cathode ray tube and the cabinet forming the appearance of the product becomes unstable, which lowers the productivity and productability of the product, and the shielding film according to the adhesion and durability of the welding part. Since the line / plane resistance of (24) changes, electromagnetic shielding performance also degrades in the long run.

Next, according to the ultrasonic welding method, an ultrasonic installation for drilling holes to the conductor layer 242 and a precise work process for welding the connection of the ground wire 30 and the conductor layer 242 after the hole are required are required. Productivity and commodity property fall.

The present invention is to solve the above-mentioned conventional problems, the shielding film and the reinforcing band of the ground connection method is simple, the grounding state is maintained firmly, the electromagnetic shielding structure of the flat cathode ray tube to help improve the productivity and productability of the product It is for the purpose of providing.

1 is a cross-sectional view showing the structure of a general planar cathode ray tube.

Figure 2 is a cross-sectional view showing the configuration of a shielding film applied to the electromagnetic shielding structure of the planar cathode ray tube according to the prior art.

3 is a cross-sectional view showing the grounding structure of the shield film and the reinforcing band in the electromagnetic shielding structure of the planar cathode ray tube according to the prior art.

4 is a cross-sectional view showing the grounding structure of the shielding film and the reinforcing band in the electromagnetic shielding structure of the planar cathode ray tube according to the embodiment of the present invention.

5, a and b are cross-sectional views showing a scratch method of the shielding film in an embodiment of the present invention.

6A, 6B, and 6C are state diagrams illustrating a process of connecting the shielding film and the reinforcing band in the electromagnetic shielding structure of the planar cathode ray tube according to the present embodiment.

<Explanation of symbols for the main parts of the drawings>

12 panel 20 safety glass

22: reinforcing band 24: shielding film

241: antifouling layer 242: conductor layer

243: PET layer 244: adhesive layer

245: protective film 30: grounding tape

40: conductive filler 50: pressure roller

The electromagnetic wave shielding structure of the planar cathode ray tube provided to achieve the above object comprises: a shielding film composed of a pollution prevention layer, a conductor layer, a PET layer, an adhesive layer, and a protective film and attached to a safety glass; It includes a reinforcing band mounted to surround the edge of the panel and grounded with the shielding film, and the conductive layer is partially exposed to the conductive layer is partially exposed by removing the contamination prevention layer and the PET layer of the shielding film. The grounding tape connected to the reinforcing band is connected to the conductive filler so that the shielding film and the reinforcing band are grounded.

Here, the anti-pollution layer and the PET layer removing operation of the shielding film is made of a scratch method by scratch means such as iron brush or sand paper, the conductive filler is made of a mixed material of the conductive component and the adhesive component.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 4 through 6C, and like reference numerals will be given to like parts of the present invention.

The electromagnetic wave shielding structure of the planar cathode ray tube according to the embodiment of the present invention is mounted in a form surrounding the edge of the shielding film 24 and the panel 12 attached to the safety glass, as shown in Figure 4 the shielding film 12 And a reinforcing band 22 grounded.

Here, the grounding structure of the shielding film 24 and the reinforcing band 22, partially removing the anti-fouling layer 241 of the shielding film 24 to partially expose the conductor layer 242, and then to the exposed portion The filler 40 is injected and the ground tape 30 connected to the reinforcing band 22 is connected to the conductive filler 40 (see FIG. 6A).

Removal of the anti-fouling layer 241 of the shielding film 24 is to use a so-called scratch method using a scratch (scratch), such as iron brush or sand paper, the exposure of the conductor layer 242 by the scratch method is shown in FIG. As shown in a, the shielding film 24 is scraped so as to completely penetrate, and each layer forms a stepped jaw, so that the conductive layer 242 is partially exposed, and as shown in FIG. Scraping only 241, it is divided into a non-penetrating manner to form a type of groove having a bottom surface of the exposed conductor layer 242.

The conductive filler 40 is made of a material in which conductive components such as graphite and silver powder and an adhesive component are mixed, and an aluminum material is used as the ground tape 30.

Referring to the method of grounding the shielding film 24 and the reinforcing band 22 in the present embodiment as described above are as follows.

First, attach the shielding film 24 to the safety glass 20, as shown in Figure 6a, and then scrape off the shielding film 24 out of the effective screen with an iron brush or sandpaper to remove the contamination prevention layer 241 by conducting Body layer 242 is partially exposed.

After exposing the conductor layer 242, the conductive filler 40 is filled, as shown in FIG. 6B, wherein the filling amount of the filler 40 should not overflow outside the recess.

6C, the ground tape 30 is attached to the filler 40, and the ground tape 30 is pressurized by using the pressure roller 50 or the like. In this case, the conductive filler 40 containing the adhesive component is included. ), The ground tape 30 and the conductive filler 40 are strongly adhered to the ground, and the ground tape 30 in close contact with the filler 40 does not protrude and forms approximately the same plane as the outer surface of the shielding film 24. Done.

Therefore, according to the present embodiment, a simple method of partially scraping off the shielding film 24, filling the conductive filler 40, and then attaching the grounding tape 30 to the filler 40 as described above is adhered. Thus, the conductor layer 242 and the reinforcing band 22 of the shielding film 24 can be connected to the ground, and since the contact area between the ground tape 30 and the conductive filler 242 is large, the energized state is stably maintained to shield the electromagnetic waves. Performance does not decrease.

Moreover, since the adhesive part of the grounding tape 30 does not protrude, the mating state of a cabinet and a cathode ray tube becomes firm.

As described above, according to the present invention, the conductor layer of the shielding film and the grounding tape can be connected in a simple manner, and the electromagnetic shielding performance is improved because the conduction state of the shielding film and the conductor layer is stably maintained. It is helpful to improve productivity and commerciality of a television or a monitor to which a cathode ray tube is applied, such that the adhesion portion of the cathode ray tube is not protruded, so that the state of the cabinet and the cathode ray tube is firmly formed.

Claims (3)

Consists of a pollution prevention layer, a conductor layer, a PET layer, an adhesive layer and a protective film, the shielding film is attached to the safety glass, Reinforcing band mounted to surround the edge of the panel and grounded with the shielding film It includes; The anti-contamination layer and the PET layer of the shielding film are partially removed, so that the conductive filler is injected into the exposed portion while the conductor layer is partially exposed, and the grounding tape connected to the reinforcing band is connected to the conductive filler, thereby shielding the film and the reinforcing band. Shield structure of flat cathode ray tube with ground. The method of claim 1, Removal of the anti-pollution layer and the PET layer of the shielding film is an electromagnetic shielding structure of a flat cathode ray tube, characterized in that the scratch method made by scratch means such as iron brush or sand paper. The method of claim 1, The conductive filler is an electromagnetic shielding structure of a flat cathode ray tube, characterized in that the conductive component and the adhesive component is made of a mixed material.