KR100201150B1 - Anti-explosion band connecting method of cathode ray tube - Google Patents

Abstract

The present invention discloses an improved method of joining a CRT explosion-proof band.

In order to solve the problem of spot welding, a joining method for forming a bead at the end of a shrinking van or the like has been proposed, which has a risk of separating the end when a large tensile force is applied.

In the present invention, two wedge-shaped protrusions extending in opposite directions to each other were formed to prevent the separation of the ends, and the change in the tensile strength of the band did not occur over time by the strong elastic nodes formed by the protrusions.

Description

Explosion proof bonding method of CRT

1 is a perspective view showing a joining method by welding.

2 is a partial perspective view of the explosion-proof band bonded by bidding.

3 is a cross-sectional view showing a mechanism configuration for bidding the explosion-proof band of FIG.

4 is a perspective view showing a joint according to the present invention.

Figure 5 is a perspective view showing the configuration of the bonding apparatus of the present invention structure.

6 (a) and 6 (b) are plan and side cross-sectional views showing the action of the joint according to the present invention.

* Explanation of symbols for main parts of the drawings

1,2: end (of explosion-proof band) 3; 3a, ab: (wedge shaped) protrusion

P: punch S: stripper

D: die C: forming cavity

F1: shearing force F2: tensional force

The present invention relates to the production of CRT, and more particularly to a method for joining the explosion-proof band.

As is well known, a cathode ray tube is an apparatus for generating an electron beam by focusing and accelerating hot electrons, deflecting the electron beam, and selectively emitting a fluorescent surface to display an image.

In order to efficiently accelerate the electron beam, a vacuum state is required because no gas particles exist in the path, and a high voltage of several tens of kV is used to control the electron beam, and thus a vacuum state is also required for breakdown voltage characteristics. Is maintained at a high vacuum of about 10 ^-7 Torr.

As a result, a large vacuum stress is generated in the CRT due to a difference from the external atmospheric pressure, which causes the panel face and funnel to shrink and cause a deformation of the panel skirt. do.

In this state, the CRT is easy to be simplified by initial defects such as scratches or external shocks, and thus generally compensates for the vacuum stress by introducing a predetermined tensile force by winding the explosion-proof band around the periphery of the skirt.

The method of applying the tensile force to the explosion-proof band is largely classified into tension banding and shrink banding.Tension banding is a method of joining ends by winding a band with a predetermined tensile force on the outer periphery of the CRT. to be.

On the other hand, shrink banding is a method in which a large thermal expansion rate of a metal band is used to introduce a tensile force by cooling a cover of a thermally expanded explosion-proof band manufactured on a skirt.

In any banding method, a welding method, in particular, a spot welding method, is used for joining a band. In the spot welding method, as shown in FIG. 1, the block electrode E1 is contacted on one side with the two end parts 1 and 2 of the band overlapped, and the welding electrode is welded with one or more welding tips E2 on the other side. It is a kind of resistance welding method which pressurizes electricity and forms the welding point (W).

This spot welding method has been used as a natural means for joining the explosion-proof band, but practically, it has various problems. That is, a large capacity power supply is required, the power consumption and large economic problems, as well as the material properties are changed by the heat effect of the welding area, the non-conductive material or its plated material is impossible to join.

Accordingly, there have been attempts to use a joining method other than welding when manufacturing an explosion-proof band of shrink banding that can be independently joined.

The present practical use is a bidding method as shown in FIG. 2, which overlaps the two ends 1 and 2 of the band to form a plurality of beads 3 by press firing to form a bead. It is a structure which was made to join. This joining method can be made only by the press die, so that the joining is very fast and economical and does not have any material limitation or residual influence.

However, in this bonding method, the bead 3 has a punch (P) as shown in FIG. 3 by simply protruding a part of the plate of the two ends (1, 2) with respect to the die (D). It is composed.

Accordingly, the tensile force acting on the bonded band acts as a shear force on the portion of the bead 3, and the portion resisting the shear force is substantially the inner protrusion 3a of the bead 3 (the upper protrusion in FIG. 3). Since there is no outside, a very large shear stress is applied to the inward protrusion 3a of the bead 3.

However, as is well known, all the structural deformations are made in the direction of least energy consumption, and the inner protrusions 3a and the outer protrusions 3b are joined by a wedge action only in the plane direction of the plate and out of plane ( Since no restraint is made in the outward direction, the inner and outer protrusions 3a and 3b move relative to each other out of the plane, so that the combined state is separated, instead of resisting the shear force by the shear deformation of the inner protrusions 3a. Is easier.

In other words, the explosion-proof band bonded in the configuration shown in Figs. 2 and 3 has a high possibility that the ends (1, 2) will be separated when a tensile force of any size is applied. This problem is particularly high in risk of failing to achieve the function of the explosion-proof band, since the explosion-proof band may be disassembled due to the conditions in which a large tensile force may be rapidly applied, for example, when the explosion-proof tube is disassembled.

The explosion-proof band, on the other hand, remains in high tension once it is mounted in the CRT. In this high tension state, the explosion-proof band is called creep deformation, which is a property of almost all structural materials, which is a phenomenon in which the deformation gradually increases when a load is applied. The tensile force shows a change over time, which gradually decreases over time.

In view of such a conventional problem, an object of the present invention is to provide a method of joining an explosion-proof band that does not separate upon application of a tensile force and does not change over time with the tensile force.

In order to achieve the above object, the joining method according to the present invention is characterized by forming at least two wedge-shaped protrusions extending opposite to each other in the direction of crossing the ends of the overlapping bands.

According to this structure, joining is also simple and the edge part of a band does not separate in any direction, and the tension | tensile force is kept constant by its elasticity.

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

In FIG. 4, two end portions 1, 2 of the explosion-proof band overlap each other, and are formed by joining two wedge-shaped protrusions 3; 3a; 3b which cross and extend in opposite directions.

Here, the wedge shape means that the size of one end is larger than the size of the other end, so that the width of the protrusion 3 may increase from one end to the other end, or may be configured to increase in height. do.

Such two wedge-shaped protrusions 3 can be formed very simply by a press mold as shown in FIG. 5, and in the upper die, two trapezoidal punches P arranged in opposite directions to each other are stripper S. Located between the dies, the lower die is provided with a die D, which is also formed of a tetrahedral forming cavity C, which forms the contour of the protrusions 3, and dies the two ends 1, 2 of the band. When the punches P and the dies D are moved relative to each other on (D), the protrusions 3 are formed to bond the bands together.

According to such a structure, not only is it very stable, but also the joint can be maintained to maintain the overall tensile force. First, the shearing force F1 in the direction crossing the band is formed by the wedge action of the two protrusions 3a and 3b. 2) remains stable without separation.

On the other hand, for the tensile force F2 in the band axial direction, as shown in FIG. Elasticity, that is, it is maintained without significant deformation due to the tensile force (F2) introduced due to rigidity, and even if the band sags due to change over time, such as creep, two U-shaped elastic nodes pull the band to pull the tensile force (F2). ) Will remain unchanged.

At this time, even if the external force is applied in the up and down direction of FIG. It is possible to resist the tensile force (F2) in a stable state without.

Such a method of the present invention is mainly applied to the explosion-proof explosion-proof band, it has an effect that can easily join the explosion-proof band that provides a stable reinforcement without changing the tensile force of the explosion-proof band is separated or introduced.

Claims (3)

A method of joining both ends of an explosion-proof band of a CRT by press firing, wherein at the end, two wedge-shaped protrusions crossing each other and extending in opposite directions are formed. The explosion-proof band bonding method of the CRT according to claim 1, wherein the width of each protrusion increases gradually from one end to the other end thereof. The method of claim 1, wherein each of the protrusions increases in height from one end to the other end thereof.