KR960003970B1 - Braun tube manufacturing process - Google Patents

Abstract

combining a panel assembly and a panel to form a bulb; removing a magnetism charged on a metal components within the bulb; and discharging dust and other contaminations remaining on the bulb.

Description

Manufacturing method of CRT

1 is a flow chart showing a conventional manufacturing method,

2 is a flow chart showing a manufacturing method according to the present invention,

3 is a perspective view showing a schematic configuration of an element device used in the method of the present invention.

* Explanation of symbols for main parts of the drawings

B: Bulb F: Frame

C: Degaussing coil CRT: Control unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a brown tube, and more particularly, to a method for producing a color brown tube having a metal porous part therein.

As is well known, a CRT is an image display apparatus that displays an image by selectively emitting a fluorescent surface with an electron beam. In the case of black and white CRT, the inside of CRT does not include any parts except fluorescent surface and electron gun mount, but CRT should be equipped with color selecting means and the accuracy of landing Since it is important, various metal porous parts are provided. Looking at the shadow mask-type color CRT, which is the most widely used CRT, the shadow mask is installed at a predetermined interval on the fluorescent surface formed on the inner surface of the CRT panel. Various pore parts, such as an inner shield for preventing deflection of the electron beam by ground, and other holder springs and contact springs, are provided. Accordingly, the color CRT is manufactured by forming a fluorescent surface and a bulb on the panel, and mounting the electron gun assembly on the bulb.

In particular, the shadow mask and the frame are composed of a mask assembly integrally coupled to each other, and a stabilizing process in which the mask assembly is heated to approach its recrystallization temperature in order to balance both thermal behaviors and the like. Will go through. In this process, since the metal atoms of the shadow mask and the frame are rearranged, it becomes inevitable to have a certain degree of magnetism.

On the other hand, after the fluorescent surface is formed on the panel and each pore component is installed, as shown in FIG. 1, the funnel is sealed to the panel assembly to form a bulb. A commonly used method of sealing is to apply a paste of a thermosetting glass powder, frit, to the seal face of the funnel, and then temporarily fix the panel assembly by placing it on the panel. The frit is hardened by forming a bulb by incorporating into a vi) and heating at a temperature of several hundred degrees Celsius for a predetermined time.

The bulb sealing is completed, and before the electron gun assembly is mounted, a cleaning process is performed to discharge foreign substances such as glass powder and dust remaining in the bulb by ultrasonic horn, rammer, and compressed air injection. When the cleaning is complete, the manufacture of the CRT is completed by mounting the electron gun assembly and evacuating the CRT.

However, as described above, the mask assembly is already in a magnetic state, and the inner shield and other pore parts are also heated at the time of frit firing, resulting in non-uniform magnetism due to rearrangement of atoms. As such, the magnetism of the pore parts not only distorts the electron beam, but otherwise, metal foreign substances are attached to the foreign substances remaining in the bulb, and the metallic foreign substances are not discharged to the outside of the bulb during the cleaning process. As a result, metallic foreign materials remain in the finished CRT.In the case of CRT, internal foreign components are large and small each time the power is turned on and off. Blocking the colored holes of the mask may cause black spots on the fluorescent surface, or may be attached to the electron gun assembly, causing serious problems such as leaks or shorts.

In view of such a conventional problem, an object of the present invention is to provide a method for producing a CRT tube which can prevent the adhesion of metallic foreign substances by the pores of pores and can increase the cleaning efficiency.

The method of the present invention for achieving the above object comprises a sealing step of combining a panel assembly and a funnel to form a bulb, and a cleaning step of discharging foreign matter remaining in the bulb, the method for producing a CRT in a metal part in the bulb An element process for removing the excess porcelain is further included between the sealing process and the cleaning process.

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

2, between the sealing process of sealing the panel assembly and the funnel to form a bulb and the cleaning process of cleaning the inside of the bulb with ultrasonic waves or compressed air, etc., the magnetic elements of the pores in the bulb are formed in accordance with the characteristics of the present invention. Device processing is included. This device process is a method of removing the magnetic force of each pore part by applying a constant magnetic field to the replaced pore part. In addition, if necessary, a method of first applying a magnetic field in one direction to remove the magnetic force and then sequentially applying the magnetic fields in the other direction to remove the residual magnetic field by the applied magnetic field.

3 schematically illustrates a device device that can be used in the device process of the present invention described above. The apparatus is preferably installed at the inlet side of the cleaning process, in which a plane F is provided to surround the transfer line of the CRT bulb B fed into the cleaning process, and on the frame F at least a plurality of element coils ( degaussing coil (C) is arranged. As described above, each of the element coils C has a different magnetic direction, and an input sensor S1 and an discharge sensor S2 are provided at the inlet side and the outlet side of the frame F, respectively. When S1 detects the entrance of the device B of the present invention to the bulb B, the control unit CTR drives the respective element coils C at the same time or sequentially to decompress the bulb B, and the discharge sensor S2 bulbs. Preferably, the discharge of (B) is configured to stop the operation of the element coil (C).

Since the distance between the bulb B and the element coil C and the magnetic strength of the element coil C vary depending on the tube type of the bulb B to be demagnetized, they are stored in the control unit CTR to be changed as necessary. It is desirable to set.

In this way, when the pore component of the present invention is demagnetized before the cleaning process is put in, the metallic foreign matter in the bulb is separated from the pore component like other foreign substances, which is advantageous in the bulb. Accordingly, when the bulb is impacted with an ultrasonic horn or rammer and blown with compressed air in the cleaning process, metallic foreign substances are discharged from the bulb together with other foreign substances. Therefore, the CRT manufactured by completing the mounting and exhausting is free of metallic foreign matter, which causes a particularly serious problem. Accordingly, clogging or electrical defects are not generated, and the present invention has a great effect on improving the quality and reliability of the color CRT.

Claims (1)

A method of manufacturing a CRT comprising a sealing step of combining a panel assembly and a funnel to form a bulb, and a cleaning step of discharging foreign matter remaining in the bulb, wherein the device process of removing magnetism from the metal parts in the bulb is provided. Method of producing a CRT tube, characterized in that further included between the sealing step and the cleaning step.