JPH061665B2 - Method for manufacturing cathode ray tube - Google Patents

Description

The present invention relates to a method of manufacturing a cathode ray tube used in a television picture tube, a terminal display device, or the like.

[Outline of Invention]

INDUSTRIAL APPLICABILITY The present invention avoids the implosion that occurs in the substantial quenching process after the evacuation process for increasing the vacuum degree in the tube to prevent the implosion of the cathode ray tube.

[Prior Art] In a cathode ray tube in which the inside of the tube is evacuated to a high degree of vacuum, since a large pressure almost equivalent to the atmospheric pressure is applied from the outside, an abnormal external force is applied for some reason or the tube body When a scratch is generated on the tube, the tube body is suddenly compressed, and the tube body is impacted and broken, so that the glass is scattered, which is extremely dangerous. Therefore, in a cathode ray tube of this type, generally, the stress due to the external atmospheric pressure is concentrated particularly toward the outside, and the corner portion in front of the tube is tightened from the outer periphery. That is, a metal band around the panel,
Even when the so-called tension band is tightened and the airtightness of the tubular body is broken, measures are taken to avoid the occurrence of implosion such as glass scattering.

Usually, this explosion-proof means is provided after the assembly and exhaust of the cathode ray tube, but in practice, the exhaust in the manufacturing process of the cathode ray tube is performed under high temperature heating in a heating furnace at about 400 ° C, for example. After the exhaust treatment, the pipe body is rapidly cooled in a state where the pipe body is taken out from the superheater furnace. For this reason, at this time, if the tube body is scratched or if an external mechanical shock is applied, implosion occurs. In particular,
The number of such accidents has been increasing with the recent increase in size and flat panel of cathode ray tubes.

[Problems to be solved by the invention]

The present invention provides a method of manufacturing a cathode ray tube capable of effectively solving the implosion accident described above.

[Means for solving problems]

The present invention is a method of manufacturing a cathode ray tube having a heating and exhausting step, in which a metal band for implosion prevention is tightened around the front outer periphery of the tubular body before the heating and exhausting step. Prior to the tightening of the metal band, a heat resistant heat insulating material is wound around the arrangement part of the metal band.

[Action]

As described above, in the present invention, the metal band is tightened before heating and exhausting, that is, explosion-proof means is applied, so that it is left standing after exhausting, or in its handling state,
It is possible to avoid the occurrence of implosion accidents and eliminate them due to this implosion.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, for example, a glass panel portion (1) having a color fluorescent surface formed on the inner surface thereof is frit-sealed to a funnel portion (2) to form a tube (3), which is then formed. Insert the electron gun assembly (5) into the neck (4), and attach the electron gun assembly (5).
Attach the glass stem (6) at the base of the neck to the neck (4).
After fusion bonding to the end of, the panel part (1) around the skirt, or the panel part (1) the funnel part (2) and the frit seal part over the entire circumference, a heat-resistant heat insulating material (7), for example, Stick the glass cloth tape. This heat resistant insulation (7)
Can be a double-sided adhesive type in which a pressure sensitive adhesive is applied on both sides. By using the double-sided adhesive tape as the heat-resistant heat insulating material (7) as described above, the heat-resistant heat insulating material (7) can be easily attached to the pipe body. Then, the metal band (8) is tightened on the heat resistant heat insulating material (7), but in this case, the metal band (8) is
Weld both ends of the metal band and pre-install this metal band (8)
It is formed in a ring shape according to the outer peripheral shape and size of the tubular body of the portion to be subjected to the treatment. Then, the ring-shaped metal band (8) is fitted onto the heat resistant heat insulating material (7). In this case, in order to carry out the fitting smoothly, prior to the fitting of the metal band (8), a portion to which a particularly large tightening pressure is applied by the metal band (8) on the heat resistant heat insulating material (7), for example, As shown in the figure, the metal band is provided near the corner of the panel part (1) and the part corresponding to the welded part of the end part of the metal band (8).
A thin piece (9) having a small frictional resistance with respect to (8), such as a steel tape, is placed on the heat-resistant heat insulating material (7) and in front of this so that it sticks. In this case, as described above, the heat resistant heat insulating material
When using a double-sided adhesive tape as (7), this thin piece (9)
It can be easily attached to the heat resistant heat insulating material (7). Place the panel part on the thin piece (9) arranged in this way.
Tighten the metal band (8) on the heat-resistant end heating agent (7) so that the metal band (8) slides in from the front of (1). The degree of tightening of the metal band (8) at this time is selected to be about 20 to 50% of the amount of deformation of the panel part (1) that occurs during evacuation when the metal band (8) is not tightened. To do.

Then, exhaust processing is performed. This exhaust treatment is performed through an exhaust thin tube, a so-called chip-off tube (10), which is provided so as to penetrate the glass stem (6), and after exhausting, this is chip-off to hermetically seal. This exhaust is piped as usual
It is carried out, for example, under heating at 400 ° C. in a state where (3) is put in a heating furnace.

After evacuation, the tube body (3) is taken out from the heating furnace. After that, the thin piece (9) protruding from the metal band (8) is cut off.

By the way, during the exhaust treatment, since the metal band (8) is in a high temperature heating state, it expands due to thermal expansion and there is no tightening effect, but in such a high temperature heating state, implosion is unlikely to occur. Even if concentration occurs at this time, since the tube body is present in the heating furnace, there is no danger of injury to humans, articles, etc. due to glass scattering.

In the example described above, the metal band (8) is tightened after the electron gun is placed, but in some cases, the metal band (8) should be attached before the electron gun is placed. It is also possible to tighten with the procedure described above. In the example described above, the panel part (1) is frit-sealed to the funnel part (2), and then the metal band (8) is tightened. Metal band around
It is also possible to place (8) tightly by the procedure described above and then frit seal this panel part (1) to the funnel part (2).

〔The invention's effect〕

As described above, in the present invention, the metal band is tightened, that is, the explosion-proof treatment is performed before the exhaust treatment, so that the implosion accident based on the substantial rapid cooling after the exhaust treatment can be avoided as described at the beginning. , Work safety can be increased.

The metal band (8) is fitted into the front outer periphery of the pipe body in a state where it is heated and stretched, but at this time, the heat-resistant heat insulation is provided between the metal band (8) and the glass surface of the pipe body. Since the material (7) is interposed, it is possible to avoid causing thermal strain in the pipe body due to this heat. Further, when the metal band (8) is fitted into the above-mentioned thin piece (9), the fitting can be smoothly performed, so that the heat-resistant heat insulating material (7) is torn and the glass surface is directly attached. By making contact, mechanical damage due to scratches and thermal damage can be avoided.

[Brief description of drawings]

FIG. 1 is a front view of a cathode ray tube used for explaining a method of manufacturing a cathode ray tube according to the present invention, FIG. 2 is a side view thereof, and FIG. 3 is a side view showing a part of a main part thereof in section. (1) is a panel portion, (2) is a funnel portion, (3) is a tubular body, (7) is a heat resistant heat insulating material, (8) is a metal band, and (9) is a thin piece.

Claims (1)

[Claims] 1. A method of manufacturing a cathode ray tube having a heating and exhausting step, wherein a step of tightening a metal band for implosion prevention on the front outer periphery of the tube body before the heating and exhausting step, and a step of tightening the metal band, And a step of winding a heat resistant heat insulating material around the arrangement portion of the metal band.