JP2594962B2 - Exhaust pipe sealing method for cathode ray tube - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for sealing an exhaust pipe of a cathode ray tube.

[Prior Art] A cathode ray tube has a fluorescent screen, an electron gun, and a color selection electrode in a color cathode ray tube in an envelope. In these cathode ray tubes, it is necessary to evacuate the inside of the envelope to a vacuum. This is generally performed via an exhaust pipe provided in the stem. In this exhausting step, as shown in FIG. 2, an exhausted structure in which a panel section 1, a funnel section 2, and a network section 3 and a stem 5 sealed to the network section 3 and having an exhaust pipe 4 are respectively sealed. The cathode ray tube is formed by carrying the material 6 into the circulation processing furnace, heating, gradually cooling, etc., evacuating the envelope, and then sealing the middle of the exhaust pipe 4.

As a circulation processing furnace used for the evacuation, sealing, and the like, for example, the one shown in JP-A-61-135023 is known.

[Problems to be solved by the invention]

In the above prior art, emphasis is placed on making the shape of the sealing portion of the exhaust pipe excellent in implosion resistance, and attention is paid to the risk of implosion due to uneven temperature of the exhausted structure. However, there was a problem of implosion.

An object of the present invention is to make the shape of the sealing portion of the exhaust pipe excellent in implosion resistance and to reduce the risk of implosion caused by uneven temperature of the exhausted structure.

[Means for solving the problem]

The above object is achieved by blowing air to the envelope except for the exhaust pipe when sealing the exhaust pipe, and reducing the temperature unevenness of the envelope so as not to blow air to the sealed portion of the exhaust pipe.

[Action]

By sending air to the exhausted structure, it is possible to reduce the temperature unevenness of the envelope, and to make the shape of the sealing portion highly implosion-resistant by preventing the air from reaching the exhaust pipe sealing portion. it can.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a sectional view of an exhaust pipe sealing position of a cathode ray tube of an exhaust furnace used in the present invention. The exhausted structure 6 that has reached the sealing position seals a part 7 of the cathode ray tube exhaust pipe 4 by heating the electric heating pot 8 which is inserted through the exhaust pipe 4 and engages a pin (not shown) of the stem. At this time, the exhaust device 9 is operating. In the exhaust furnace 10, the outside air is fanned through the inlet 11.
When the air is blown by 12 and passes through the first perforate plate 13 and the second perforate plate 14, the air 15 in the furnace becomes laminar. The laminar wind 15 is blown against the exhausted structure 6 and is discharged to the outside through the exhaust port 16. That is, the exhaust pipe 4 is sealed while the temperature is lowered by blowing air to the panel section 1, the funnel section 2 and the like of the exhausted structure 6 excluding the electric heating pot 8 with the sealing position of the exhaust pipe 4.
At this time, the wind 15
Is exhausted to the exhaust port 16 so as not to flow toward the exhaust pipe 4.

According to the present embodiment, the panel portion, the funnel portion, and the like can be cooled while sealing the exhaust pipe of the exhaust hole structure, thereby preventing temperature variations in the envelope and reducing the rate of occurrence of implosion in the exhaust furnace. can do.

In the exhaust furnace used in the above embodiment, an exhaust port fan may be provided to forcibly exhaust air from the furnace.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, since the panel part of an enclosure, a funnel part, etc. are cooled, sealing the exhaust pipe of a to-be-evacuated structure, the temperature unevenness of an enclosure can be reduced and the implosion can be prevented. At the same time, the shape of the sealing portion of the exhaust pipe can be made high in implosion resistance.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an exhaust furnace used in the present invention, and FIG. 2 is a plan view of an example of an exhausted structure. DESCRIPTION OF SYMBOLS 1 ... Panel part, 2 ... Funnel part, 3 ... Network part, 4 ... Exhaust pipe, 5 ... Stem, 6 ... Exhausted structure,
8 ... electric heating furnace, 9 ... exhaust system, 10 ... exhaust furnace, 11 ...
Inlet, 12… Juan, 13, 14… Perforate plate, 15… Wind, 16… Exhaust.

Claims (1)

(57) [Claims] 1. A shallow dish-shaped panel portion forming a fluorescent surface on the inner surface of a closed end, a funnel portion having one end sealed to the panel portion, and a neck portion having one end sealed to the other end of the funnel portion. And an exhaust pipe provided on a stem sealed to the other end of the neck portion of the envelope, and after exhausting the inside of the envelope, sealing the exhaust pipe A method of sealing an exhaust pipe of a cathode ray tube, wherein the exhaust pipe is sealed while lowering the temperature of the panel portion and the funnel portion by blowing outside air to the envelope. .