JPS5837258B2 - Manufacturing method of deflection tube body of cathode ray tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a deflection tube body of a cathode ray tube and a mold thereof.

Cathode ray tubes for television receivers are made of glass and have a special shape, so they are divided into three parts: a cylindrical tube into which the electron gun is inserted, a deflection tube, and a video image section. These three parts are finally welded together to form an integral part.

However, the deflection tube is a tube that expands from the cylindrical tube to a phantom almost pyramidal shape, but regarding its manufacture,
Conventionally, methods such as pouring molten glass into a mold or heating and press-forming a flat glass plate have been adopted.

However, in some mold-based forming methods, if the molten glass does not flow well, air bubbles may form within the glass wall thickness, and air trapped within the mold often causes mold sag or sink marks. .

For this reason, it is extremely difficult to obtain a homogeneous shaped product suitable for use as a cathode ray tube, resulting in poor yield.

Furthermore, press molding requires the production of convex and concave molds, and since the mold is forced into a certain shape, it may cause clouding on the surface of the molded product or distortion in the wall thickness. Therefore, the quality of some shaped products is poor, and many of them are unsuitable for use as cathode ray tubes.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned drawbacks and provide a method and apparatus for manufacturing a deflection tube body for a cathode ray tube that has a homogeneous and smooth surface.

In the method of the present invention, a glass plate with a hole punched in the center in advance is placed on a convex or concave shape of a deflection tube made of carbon and supported by a conveying means such as a conveyor, and the glass plate is held at a certain height. The glass plate is transferred to a furnace having a certain length and a slow heating and slow cooling means such as electric power, and in the furnace, the glass plate is softened by slow heating and naturally bends and descends. The purpose is to form a 0-deflection tube body by bringing it into close contact with the surface of a mold by its own weight and then slowly cooling it.

This method will be explained in detail with reference to the drawings.

FIG. 1 shows a cathode ray tube used, for example, in a battery-powered small television receiver.
and a video screen section 3.

As described above, each of these parts is manufactured individually and finally integrated.

The deflection tube body 2 in this cathode ray tube is manufactured as follows according to the method and mold of the present invention.

As shown in FIG. 2, the mold 4 supported by a conveying means such as a conveyor is a convex mold 5 made of carbon and having a cross section in the shape of the internal space of the deflection section tube 2. Approximately cylindrical protrusions 6 having the shape of the internal space of the cylindrical tube body 1 are connected and integrally formed.

A peripheral wall 8 continuing to the bottom portion 7 is provided around the convex shape 5,
It surrounds the convex shape 5.

Note that this peripheral wall 8 does not necessarily have to be provided, and may be omitted if a large number of convex molds 5 are integrally formed.

The protrusion 6 slightly protrudes from the peripheral wall 8 so that the glass plate 9 can be easily inserted into the protrusion 6.

The glass plate 9 is a rectangular plate of good quality with a predetermined wall thickness, and has an area capable of naturally bending when heated and softened to surround the entire outer periphery of the convex mold 5.

In the center of this glass plate 9 is a hole 1 that can fit into the protrusion 6.
0 is pre-drilled, and this glass plate 9 is the precept type 4.
When the glass plate 9 is supported by and transferred into the furnace, the hole 10 is inserted onto the protrusion 6, and the glass plate 9 is latched by the scrap portion 5' of the convex mold 5, so that the glass plate 9 is supported substantially horizontally.

Therefore, when the glass plate 9 is not decorated, it does not fall downward.

The rectangular mold 4 on which the glass plate 9 is placed in this manner is sent via a conveyance means to a furnace having an annealing means.

The furnace having the slow heating and slow cooling means is aimed at mass production and has a certain length so as to be most suitable for implementing the present invention.

In other words, the purpose is for the material carried into the furnace to be in a state where it has already been shaped and cooled and solidified when it is sent out from the furnace end.

In this case, an electric heater is used as the heating source, and the heating power can be adjusted so as to create a temperature distribution suitable for shaping the glass material.

The furnace also has a certain height, which is relatively small, for example around 45 cm.

Therefore, the deflector body of a cathode ray tube suitable for manufacturing in such a furnace is for use in small television receivers of about 5 inches at most.

However, if the height of the furnace is increased and other specifications are changed and the furnace is designed and manufactured, it is possible to manufacture a furnace for receiving and storing large-sized televisions.

As the oval mold 4 sent to the furnace moves through the furnace while being heated by the electric heater, the glass plate 9 melts and becomes soft.

In this case, the addition is done gradually, so that the glass plate 9 is only softened while maintaining a uniform shape as a whole, so the predetermined quality of the glass plate 9 is maintained and it is natural without internal distortion. You will be able to flex.

Therefore, if the temperature is adjusted so that the glass plate 9 does not completely melt while moving in the furnace, the glass plate 9 will become soft and droop downward due to its own weight. Become.

However, since the hole 10 of the glass plate 9 is only latched by the scrap part 5l of the convex mold 5, the hole 10 itself does not enlarge, and therefore the end sides 9', 9' of the glass plate 9 are not enlarged.
It hangs down from there and attaches to the outer circumferential surface of the convex mold 5.

In this way, the glass plate 9 is attached to the outer peripheral surface of the convex mold 5, and the deflection section tube 2 is almost formed.

When the glass plate 9 has come into close contact with the outer circumferential surface of the convex mold 5 and has a complete shape, it is then slowly cooled.

Therefore, the glass plate 9 is not heated more than the above, but is gradually solidified and its shape is stabilized.

For this reason, the precepts that come out of the furnace are almost completely solidified.
By removing the mold, it can be taken out as a zero product.

According to the above manufacturing method, if the glass plate 9 is given a sufficient area to cover the entire outer peripheral surface of the convex mold 5, the glass plate 9 will be folded at the hem, that is, at the bottom of the convex mold 5. may polymerize and cause wrinkles.

Therefore, in order to eliminate this inconvenience, as shown in FIG. I'll put it here.

The weight 12 is made of an appropriate weight that does not interfere with the softening of the glass plate 9 and its close contact with the convex mold 5, and is mainly made of carbon or metal.

Therefore, by lowering the weight 12 while being placed on the edge of the glass plate 9, the edge can be formed into a convex shape without wrinkles and brought into close contact with the glass plate 9.

In this case, the edge of the glass plate 9 on which the weight 12 is placed may be formed as the outer peripheral edge 13;
This outer peripheral edge 13 is unnecessary and must be removed when producing a product, but since it is pressed down by the weight 12 and becomes thinner, it can be easily removed.

Also, for convenience in cutting this, weights 14 and 15 as shown in FIGS. 4 and 5 can be used.

That is, the weight 14 is of course a rectangular annular body, but its lower surface has peaks 14', 14' on both sides, and an indented recess 14'' is formed between the peaks 14'. It is formed.

Therefore, when the glass plate 9 softens and comes into close contact with the convex mold 5, it descends while pressing its lower end surface and bites into the lower end part under its own weight.

Therefore, the peak 14' close to the convex shape 5 forms a groove at the lower end of the glass plate 9.

On the other hand, the remaining portion of the softened lower end of the glass plate 9 enters the recess 14''.

Thus, when the deflection section tube 2 made of the glass plate 9 is slowly cooled and solidified, it becomes easy to break the entire outer periphery r from the groove formed by the crest 14' and remove it. .

On the other hand, the weight 15 has only one peak 15' compared to the weight 14, and the tip of the peak 15' is made at an acute angle.

Therefore, this peak 15' acts to cut the outer peripheral edge 9'' at the lower end of the softened glass plate 9 by its own weight.

Furthermore, even if the glass plate is not cut by its own weight, since the tips of the peaks 15' are sharp, the grooves formed in the glass plate will be deep, making it easier to break when solidified.

In addition, as far as the above is concerned, the glass plate 9 is a rectangular plate having an area sufficient to cover the outer circumferential surface of the convex mold 5, but when doing so, it is necessary to use a weight as described above. , Therefore, in order to eliminate the inconvenience of using this, it is also possible to make special improvements to the glass temporary 9.

That is, as shown in FIG. 6, cutouts 16 are formed in advance into each side of the rectangular glass medium 9.

In this case, the length a on the diagonal from the hole 10
is a length that can sufficiently include the length of the convex mold 5 by taking into account the expansion coefficient of the glass, and the length of lb from the hole 10 to the center of each side of each side of the convex mold 5. The notch has a roughly semi-elliptical indentation so that it can fully accommodate the length of.

Therefore, when the glass plate 9 is softened and brought into close contact with the convex mold 5, the lower ends are almost aligned, and the extra outer peripheral edge as described above is not formed.

What has been described above is a case where the convex mold 5 is used, but next, a method for manufacturing the deflection section tube body 2 using a concave mold will be explained.

As shown in FIG. 7, the concave mold 17 has a bowl-shaped cross-section of the deflection section tube 2 that opens toward the hole at the inner bottom of the oval mold 18 made of carbon, and a comparative A conical column 21 which forms a steep slope 19 and stands from the center of the inner bottom 20 is integrally formed.

The opening of the slope 19 is made approximately the same area as the glass plate 9 at the uppermost end.

The hole 10 in the glass plate 9 fits into the head of the conical column 21.

The conical column 21 guides the hole 10 when the glass plate 9 softens and descends onto the concave mold 17.

The upper opening of this oval mold 18 is quadrilateral, but the inner bottom 20 is circular.

Therefore, when this mold is supported on a conveyor and transferred into the furnace as described above in the state shown in FIG. The hole 10 is guided by the conical column 21 and descends vertically to come into close contact with the inner bottom portion 20, and also comes into close contact with the inner circumferential surface of the concave mold 17 as a whole.

After being formed into a certain shape in this manner, it may be subjected to an annealing process, and then demolded and manufactured into a product.

In this case as well, it would be desirable to use the glass plate 9 shown in FIG. 6.

According to the present invention described above, demolding is easy because a mold made of carbon is used, and a rectangular glass plate with a hole in the center can be formed into a shape without using casting or pressing. The glass plate is placed on a mold and transferred to a slow-heating and slow-cooling furnace.The glass plate softens and naturally flexes under its own weight, adhering tightly to the oval mold.The surface of the molded deflection tube body is extremely smooth, free from scratches, and cloudy. There is no internal distortion.

Additionally, the excess outer periphery during molding can be easily removed by using a weight, which is extremely convenient for production.

This method is most suitable for mass production, and has the advantage of being able to use existing slow-heating and slow-cooling furnaces.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a cathode ray tube for a small television receiver, Fig. 2 is a sectional view showing a convex type, and Fig. 3 is a sectional view showing a convex type.
The figure is a partial cross-sectional view showing a certain type of structure that uses a weight on a glass plate, Figures 4 and 5 are partial cross-sectional views showing the action of the weight, and Figure 6 is a deflection tube. FIG. 7 is a plan view showing a glass plate having a shape, and FIG. 7 is a cross-sectional view showing a state in which a deflection tube body is to be manufactured using a concave mold. DESCRIPTION OF SYMBOLS 1...Cylindrical part tube body, 2...Deflection part tube body, 3...English surface part, 4, 18...Original type, 5 ...Convex, 5'...Shoulder, 6.
...Protrusion, 9...Glass plate, 10...
... Hole, 12, 14, 15 ... Weight, 9",
13...Outer peripheral edge, 14', 15'...
- Mountain part, 14"...concave part, 16...notch, 17...concave shape.

Claims (1)

[Scope of Claims] 1. It is supported by a conveying means such as a conveyor, has a substantially cylindrical protrusion in the center, and has a hole in the center in advance on the convex or concave shape of the deflection tube made of carbon. A rectangular glass plate with a hole in it is placed so that the hole is fitted into the protrusion, and this is placed in a furnace having a certain height and length and equipped with an annealing and annealing means using electric power or the like. The glass plate is transferred, and in the furnace, the glass plate softens by slow heating, naturally bends and descends, and is brought into close contact with the outer circumferential surface of the certain shape mold by its own weight, and then it is slowly cooled. A method for manufacturing a deflection tube body of a cathode ray tube. 2. The method of manufacturing a deflector body of a cathode ray tube according to claim 1, wherein the glass plate has a substantially semi-elliptical notch indented on each side. 3. A rectangular piece of glass that is supported by a conveyance means such as a conveyor, has an approximately cylindrical protrusion in the center, and has a hole pre-drilled in the center on the convex or concave shape of the deflection tube made of carbon. A plate is placed so that the hole is fitted into the protrusion, and a rectangular weight with an opening in the center and an inner edge approximately equal to the outer circumference of the maximum opening of the deflection tube is placed on top of the glass plate. Hold the edge of the glass plate which has been softened by placing it on the glass plate and transfer it to a furnace having a certain height and length and equipped with slow heating and slow cooling means using electric power or the like, Deflection of a cathode ray tube characterized in that the glass plate is softened by slowing in the furnace, is naturally bent and lowered, and is brought into close contact with the outer circumferential surface of the certain shape by its own weight, and then is slowly cooled. Method of manufacturing a tube body. 4. The method of manufacturing a deflection tube body of a cathode ray tube according to claim 3, wherein a ridge is formed on the lower surface of the heavy joist, and a concave portion is formed between the ridges. 5. The method of manufacturing a deflection tube body of a cathode ray tube according to claim 4, wherein the lowermost end of the mountain portion is formed at an acute angle.