KR20050014212A - Cleaning device and method of the CRT's neck - Google Patents

Abstract

PURPOSE: A device for cleaning a neck portion of a cathode ray tube and a cleaning method are provided to maintain a constant voltage potential formed at a surface of the neck portion uniform and stable, by cleaning the neck portion through the use of plasma. CONSTITUTION: A device comprises an internal electrode(50) accommodated in a neck(30) such that the internal electrode covers an inner surface of the neck; an external electrode(60) spaced apart from an outer surface of the neck and arranged to cover the neck; a gas injection unit(40) connected to the internal electrode such that the gas injection unit injects a discharge gas and a reactive gas into the neck; and a power source unit(10) for applying high frequency power to the internal electrode and the external electrode such that foreign substances are removed from the surfaces of the neck by the plasma discharge generated between the internal electrode and the external electrode.

Description

CRT cleaning device and its cleaning method {Cleaning device and method of the CRT's neck}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CRT neck cleaning apparatus and a method for cleaning the same, wherein a plasma is generated under atmospheric pressure to enable a cleaning operation having high cleanliness even in a complicated shape of the neck, and an apparatus and method for cleaning the neck of the CRT using the plasma It is about.

The cathode ray tube (CRT) is used in all display devices that implement an image in a form that can be seen by a human eye as well as a television. An electric signal incorporating image information is generated by an electron beam. It converts and displays optical images such as figures and characters.

Three electron guns of R, G, and B that emit the electron beams are positioned in a neck portion, and the electron beams emitted from the electron guns emit light by scanning a panel coated with phosphors. Here, the neck has a diameter of about 36 mm, and the assembled three electron guns are sealed at a predetermined position.

That is, the neck part is required to have an extremely clean inner surface such that an electron gun emitting an electron beam is loaded and a high voltage is applied to emit the electron beam, so that electric field concentration does not occur near the end of embedded graphite.

The tube used for such a neck part is generally manufactured by cutting a glass tube, heating the one end, and diameter-processing it to a flare field. However, during such processing, contaminants such as particulates, fibres, or extremely thin membranes generated from glass powder, fines in the plant, oil mist, dunball cases, etc. may adhere to the inside and outside surfaces of the neck tube.

Conventionally, in order to remove contaminants attached to the inner surface of the neck part, a cleaning method using an alkaline detergent, a cleaning method using an acetic acid sponge, a vibration suppression device using high pressure air, and the like are applied.

However, the CRT neck cleaning method proposed in the related art has a high cleanness level due to a structural problem that the neck shape is complicated in a conical shape, the diameter of the neck tube is narrow, and the handling is not easy due to the glass material.

Furthermore, even after the conventional cleaning process, fine contaminants remain on the neck surface, and these contaminants interfere with the paths of the three electron beams for scanning the fluorescent surface because they cause electric field concentration and change in the trajectory of the electron beam.

1 is a measurement of an electron beam draft of a CRT cleaned by a conventional neck cleaning method. The graphs G1, G2, and G3 correspond to electron beams emitted from three electron guns and indicate convergence over time. As the three graphs G1, G2, and G3 are concentrated near 0 on the Y-axis, a better image may be displayed.

In FIG. 1, however, the convergence drift problem is generated by impeding the concentration of the three electron beams G1, G2, and G3 on the phosphor, and thus, the predetermined direction of the electron beam generated by the electron gun is changed to change the image reproduction. There was a problem that the sharpness drops.

The present invention has been made to solve the above-described problems of the prior art, and generates a plasma under atmospheric pressure to enable a cleaning operation having a high degree of cleanliness even in the complex shape of the neck portion, and the neck surface by cleaning the neck portion of the CRT using the plasma The present invention provides a CRT neck cleaning apparatus capable of maintaining a constant and stable constant voltage potential formed thereon to improve image clarity, and a cleaning method thereof.

1 is an electron beam drift graph of a CRT neck portion to which a conventional cleaning method is applied,

2 is a front sectional view of the CRT neck portion cleaning device according to the present invention;

3 is a flowchart of a CRT neck portion cleaning method according to the present invention;

4 is an electron beam drift graph of the CRT neck portion to which the cleaning method of the present invention is applied.

<Explanation of symbols on main parts of the drawings>

10: power supply unit 20: matching unit

30: neck 40: gas injection part

45: gas exhaust 50: internal electrode

60: external electrode 70: lower insulator

80: upper insulator 90: gas injection hole

According to a feature of the CRT neck cleaning apparatus according to the present invention for solving the above problems, in the neck surface cleaning apparatus of the CRT tube image is implemented by the action of the electron beam, the inside is inserted into the neck to surround the inner surface of the neck An electrode, an external electrode formed to surround the neck to be spaced apart from the outer surface of the neck, and a gas injection part connected to the internal electrode to inject a discharge gas and a reactive gas for plasma discharge into the neck; And a power supply unit for applying high frequency power to the internal electrode and the external electrode so that foreign substances on the neck surface are removed by the plasma discharge generated between the internal electrode and the external electrode.

In addition, the CRT neck cleaning method includes a first step of inserting an internal electrode into the neck of the CRT, forming an external electrode outside the neck, and injecting a discharge gas and a reactive gas into the neck; A third step of applying high frequency power to the internal electrode and the external electrode, a fourth step of generating plasma discharge inside the neck by the high frequency power supply, and a fifth step of cleaning foreign substances on the surface of the neck by the plasma Characterized in that comprises a step.

Hereinafter, the CRT neck unit cleaning apparatus of the present invention and a cleaning method thereof will be described with reference to FIGS. 2 to 4.

The present invention relates to a cleaning apparatus using a plasma, which refers to a group of charged cations and electrons generated by an electrical discharge. The plasma state is a gas that is ionized by receiving a large energy to exhibit an electrical neutrality as a whole, it can be seen that the example used for lighting such as fluorescent lamps, neon signs.

In order to create such a plasma state, a high power source must be applied. In the present invention, a power source having a frequency of RF (13.56 MHz) or microwave (2450 MHz) is applied, and plasma discharge is induced by injecting a discharge gas and a reactive gas. That is, the present invention relates to an apparatus and method for cleaning the neck surface by causing plasma discharge to react the plasma with foreign matter present on the neck surface.

Looking at the configuration of the CRT neck cleaning apparatus of the present invention with reference to Figure 2, the power supply unit 10 for applying a high frequency power to make a plasma state, the inner electrode 50 and the outer surface respectively located on the inner / outer surface of the neck portion 30 And an electrode 60, a gas injection unit 40 through which discharge gas and a reactive gas can be injected, and a gas exhaust port 45 for exhausting gas.

In more detail, first, the power supply unit 10 applies a high frequency power source having a frequency of RF (13.56 MHz) or microwave (2450 MHz) to the internal electrode 50 and the external electrode 60. The RF or microwave both supply the high voltage power required for plasma discharge, where the microwave induces plasma discharge at higher temperatures.

In addition, a matching unit 20 is provided between the power supply unit 10 and the neck unit 30 to maximize traveling waves and minimize reflected waves.

The inner electrode 50 formed on the inner surface of the neck portion 30 and the outer electrode 60 formed on the outer surface are connected to the power supply unit 10 to receive a high power source. The internal electrode 50 is preferably made of a copper pipe having good electrical conductivity and heat dissipation effect, and is manufactured in the form of a pipe (pipe) so that gas can be injected into the neck 30. To this end, the plurality of holes 90 of Φ 2 mm are formed in the internal electrode 50.

At this time, the gas injected into the neck 30 may be adjusted by using a mass flow meter or a ball parameter, and a predetermined amount is injected into the neck 30 through the hole 90. Helium, argon, nitrogen, etc. are used as the discharge gas, and a small amount of oxygen and CF4 (CARBON FLUORIDE) may be used as the reactive gas.

At this time, the discharge gas may be injected at 1 ~ 20L per minute, the coral of the reactive gas is preferably 0 ~ 20L per minute, CF4 is injected 0 ~ 500cc per minute.

The external electrode 60 may be manufactured in a form of a copper pipe or a thin plate to surround an outer surface of the neck part 30.

The lower insulator 70 and the upper insulator 80 are inserted to maintain a constant distance between the internal electrode 50 and the inner surface of the neck. Teflon is used as the insulator, and in particular, the lower insulator 70 is provided with a hole for exhausting the generated gas generated by plasma reacting with a foreign material, and a hose is connected. Such a hole is called a gas exhaust port 45. In addition, the exhaust amount may be adjusted through a valve (not shown) when exhausting the generated gas.

As the high power source of the power supply unit 10 is applied to the electrodes 50 and 60, the plasma formed between the electrodes generates ultraviolet rays, atoms, molecular radicals, ions, etc. and remains on the surface of the neck 30. Reacts with foreign bodies. As a result, the surface of the neck 30 is cleaned.

At this time, the gas exhaust port 45 is to prevent the re-adsorption of foreign substances as the concentration of the generated gas is increased in the neck 30 as the cleaning is performed by the plasma.

A process method of cleaning the neck surface by plasma discharge using the CRT neck cleaning apparatus configured as described above will be described with reference to FIG. 2.

An internal electrode, a lower insulator, and an upper insulator are inserted into the neck of the CRT, and an external electrode is formed outside the neck. The insulators 7 and 8 allow the inner electrode and the inner surface of the neck to be separated by a predetermined distance, and the separation distance is about 5 mm.

After insertion, the discharge gas (helium: 5 liters per minute) and the reactive gas (100 cc / min) are injected into the inner surface of the neck part through a plurality of holes formed in the internal electrode (S2), and a high power source having an RF or microwave frequency It is applied (S3). As a result, plasma is generated, and the plasma density is increased by increasing the power supplied from the power supply unit.

The generated plasma generates ultraviolet rays, radicals and ions in atoms or molecules, which are reacted with foreign matter on the surface of the neck to be cleaned.

As the concentration of the generated gas increases as the reaction with the foreign material by the plasma continues, the foreign material may be resorbed on the surface of the neck part, and the generated gas is discharged through the gas exhaust port to prevent this. The gas discharge can be controlled by a valve. (S6)

Figure 4 is a measurement of the drift of the electron beam of the CRT cleaning the neck using the apparatus presented in the present invention, as shown in the graph (G1 ', G2', G3 ') showing the respective electron beam paths compared to FIG. It can be seen that the deviation is small.

That is, in the case of plasma treatment, the constant voltage potential formed at the neck portion can be stabilized and the deflection of the electron beam can be prevented, so that accurate image reproduction of the CRT can be performed.

As described above with reference to the drawings illustrated with respect to the CRT neck cleaning apparatus and the cleaning method according to the present invention, the present invention is not limited by the embodiments and drawings disclosed herein, the technical spirit is protected by those skilled in the art It can be applied within the range.

The CRT neck cleaning device and the cleaning method configured as described above can clean foreign materials on any surface of the neck by using plasma discharge, and thus high level of clean cleaning is possible, and due to the removal of foreign materials on the surface of the neck part. By stabilizing the constant voltage potential formed at the neck of the electron gun, there is an effect of improving the sharpness of image reproduction through the CRT.

Claims (11)

In the neck surface cleaning device of the CRT tube, the image is realized by the action of the electron beam, An internal electrode inserted into the neck to surround the inner surface of the neck; An external electrode formed to surround the neck and spaced apart from the outer surface of the neck; A gas injection unit connected to the internal electrode and injecting a discharge gas and a reactive gas for plasma discharge into the neck; And a power supply unit for applying a high frequency power to the internal electrode and the external electrode so that foreign matters on the surface of the neck are removed by the plasma discharge generated between the internal electrode and the external electrode. The method of claim 1, The inner electrode has a CRT neck cleaning apparatus, characterized in that it has a pipe shape so that the discharge gas and the reactive gas can be injected into the neck. The method of claim 1, The inner electrode is a CRT neck unit cleaning device, characterized in that inserted into the neck spaced apart by a predetermined distance. The method of claim 3, wherein The CRT neck cleaning apparatus further comprises an upper insulator and a lower insulator respectively inserted into both sides of the neck such that the internal electrode maintains a distance from the inner surface. The method of claim 4, wherein The lower insulator is a CRT neck cleaning device, characterized in that the gas exhaust mechanism is formed so that the generated gas generated by reacting with foreign matter on the neck surface by the plasma discharge to the outside. The method of claim 5, wherein The gas exhaust pipe is a CRT neck cleaning device, characterized in that connected to the valve for controlling the discharge of the product gas. The method of claim 1, The power supply unit CRT neck cleaning apparatus, characterized in that for supplying power having a frequency of RF (radio frequency) or microwave under atmospheric pressure. The method of claim 1, And the power supply unit further comprises a matching unit positioned between the power supply unit and the neck such that the traveling wave applied to the inside of the neck is maximized and the reflected wave due to the plasma discharge is minimized. Inserting an internal electrode into the neck of the CRT and forming an external electrode outside the neck; A second step of injecting a discharge gas and a reactive gas into the neck; A third step of applying a high frequency power to the inner electrode and the outer electrode; A fourth step in which plasma discharge is generated inside the neck by the high frequency power source; And a fifth step of cleaning the foreign substance on the surface of the neck by the plasma. The method of claim 9, The second step is CRT neck cleaning method characterized in that the helium, argon or nitrogen used as the discharge gas and oxygen or CF4 used as the reactive gas is injected with the following injection amount per minute. Injection volume per minute: Helium, argon, nitrogen: 1-20 L / min, Oxygen: within 20 L per minute, CF4: within 500 cc per minute. The method of claim 9, The fifth step is a CRT neck cleaning method, characterized in that further comprising the step of discharging the generated gas generated by the plasma reacts with foreign matter on the surface of the neck.