JPH0696668A - Shield plate for forming metal film of cathode-ray tube - Google Patents

Abstract

PURPOSE:To decrease improper withstand voltage including discharge by reducing a shield amount at the time of forming a metal back, and lowering the separation of a black non-luminous material or the like from the inner surface of a panel. CONSTITUTION:The end 21a of a shield plate 21 used for the vacuum deposition of an aluminum film 14 on the inner surface of a panel 11 has convex curved surface relative to a pin 17 for supporting a color screening mechanism. In addition, the plate 21 is bent in such a way as keeping the end 21a near the pin 17. As the shield plate 21 is bent in that way, a shield amount can be reduced to sufficiently cover carbon 13 or the like. On the other hand, the shield plate 21 is bent, but the end 21a thereof is curved. Thus, even when the body of the panel 11 or the like comes in contact with the shield plate 21 at the time of mounting the panel 11 on a deposition furnace, the panel 11 easily slides along the end 21a and is hardly stranded on the shield plate 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield for forming a metal film of a cathode ray tube, which is arranged inside the panel when the metal film is formed on the inner surface of the panel of the cathode ray tube to shield the adhesion of the metal film. It is about boards.

[0002]

2. Description of the Related Art FIG. 3 shows a part of a panel of a cathode ray tube. As shown in FIG. 3, the inner surface of the panel 11 has 3
Primary color phosphor 12 and carbon 13 which is a black non-luminous substance
Are applied, and these phosphors 12 and carbon 1
3 and 3 are covered with an Al film 14 as a metal back.

The Al film 14 is provided so as to have a high potential to accelerate the acceleration of the electron beam and to increase the emission brightness of the phosphor 12 by the mirror effect. Also A
The l film 14 suppresses the fluorescent substance 12 and the carbon 13 from peeling off by pressing the fluorescent substance 12 and the carbon 13 in order to suppress the withstand voltage failure such as electric discharge caused by the fine particles of the fluorescent substance 12 and the carbon 13 peeled off from the panel 11. It is also provided to prevent it.

In order to form this Al film 14, FIG.
As shown in FIG. 1, first, the panel 11 coated with the phosphor 12 and the carbon 13 is carried by the transfer machine and then the vapor deposition pot 15
Load on top. Then, the inside of the vapor deposition kettle 15 is evacuated to heat and evaporate Al 16 in the vapor deposition kettle 15.
6 is attached to the inner surface of the panel 11.

However, the portion where the carbon 13 or the like is actually easily peeled off is a pin 17 provided on the inner surface of the panel 11 for supporting the aperture grill which is a color selection mechanism.
Is around. Therefore, the carbon 13 around the pin 17
If Al can be completely covered with Al film 14, the withstand voltage defect is reduced. However, when the Al film 14 adheres to the pin 17 itself, the Al film 14 is more easily peeled off than the carbon 13 or the like, which causes a failure in withstand voltage.

Therefore, conventionally, when vacuum-depositing the Al film 14, as shown in FIGS. 3 and 4, a flat shield plate 18 is arranged in the vapor deposition vessel 15 so as to face each pin 17, and
The Al film 14 was prevented from adhering to the pins 17. It should be noted that the frame body having a plate-like peripheral wall, which is a frame body having a plate-like peripheral wall, for preventing the Al film 14 from adhering to the inner wall surface of the vapor deposition vessel 15 itself, and a plurality of shielding plates 18 at their base end portions. It is one. Then, prior to vacuum deposition of the Al film 14,
The deposition preventive plate 19 and the shield plate 18 are fitted into the vapor deposition pot 15.

[0007]

However, in the conventional shield plate 18 shown in FIGS. 3 and 4, the adhesion of the Al film 14 cannot be shielded only in the narrow range around the pin 17 and its surroundings. The amount of shielding was too large to sufficiently cover the carbon 13 and the like.

If the shielding plate 18 is bent so as to approach the pin 17, it is possible to reduce the shielding amount and sufficiently cover the carbon 13 and the like. But if you do this,
There is a risk that the panel 11 may get on the shield plate 18 when the panel 11 is loaded on the vapor deposition pot 15. When the panel 11 rides on the shield plate 18, the shield plate 18 cannot normally shield the pins 17 and the inside of the vapor deposition pot 15 cannot be evacuated, which interferes with the process of forming the Al film 14. Occurs.

[0009]

The shield plates 21 and 22 for forming a metal film of a cathode ray tube according to claim 1 are panel 11 of the cathode ray tube.
The metal plate forming shield plate of the cathode ray tube, which is arranged inside the panel 11 when the metal film 14 is formed on the inner surface of the metal plate and shields the adhesion of the metal film 14, is provided on the inner surface. It is characterized in that the tip portions 21a and 22a which should be opposed to the pin 17 for supporting the selection mechanism are convex curved surfaces with respect to the pin 17.

The shield plates 21 and 22 for forming a metal film of a cathode ray tube according to claim 2 are characterized in that they are integrated at the base end with a frame body 19 having a plate-like peripheral wall.

The shield plate 22 for forming a metal film of a cathode ray tube according to claim 3 is characterized in that a groove 23 concave to the pin 17 is provided on the curved surface.

[0012]

A shield plate 2 for forming a metal film of a cathode ray tube according to claim 1
1 and 22 are pins 1 for supporting the color selection mechanism of the panel 11.
When the shield plates 21 and 22 are bent so as to approach the panel 7, when the panel 11 is loaded in the metal film forming apparatus 15 so as to include the shield plates 21 and 22, the main body of the panel 11 and the pin Even if 17 contacts the shield plates 21 and 22, the tip portions 21 of the shield plates 21 and 22 with respect to the pin 17
Since a and 22a have a convex curved surface, the panel 11 easily slides along the curved surface, and the panel 11 is covered by the shielding plate 2.
It is difficult to get on the 1st and 22nd

Therefore, the shielding plates 21 and 22 can be bent so as to approach the color selection mechanism supporting pin 17 without hindering the process of forming the metal film 14, and the shielding by the shielding plates 21 and 22 can be achieved. The range can be narrowed.
Therefore, the adhesion of the metal film 14 can be shielded only in the narrow range of the pin 17 and its periphery, and the shielding amount can be reduced.

In the metal film forming shield plates 21 and 22 of the cathode ray tube according to the second aspect, since the frame body 19 having the plate-like peripheral wall and the shield plates 21 and 22 are integrated, the metal film forming shield plates 21 and 22 are formed. The frame 19 and the shield plate 2 which function as an adhesion preventive plate for preventing the metal film 14 from adhering to the inner wall surface of the device 15 itself.
Easy to handle with 1 and 22.

In the shielding plate 22 for forming the metal film of the cathode ray tube according to the third aspect, the concave groove 23 is provided in the curved surface of the tip portion 22a of the shielding plate 22 with respect to the pin 17 for supporting the color selection mechanism. When the panel 11 is loaded into the device 15 for forming a metal film so as to include the shield plate 22, even if the pin 17 comes into contact with the shield plate 22, the pin 17 is guided by the groove 23 while the panel 11 is being guided. Is easy to slide along a curved surface. For this reason,
The panel 11 is accurately positioned in the circumferential direction with respect to the shield plate 22, and the pin 17 and the shield plate 22 face each other accurately.

[0016]

The first and second embodiments of the present invention will be described below.
A description will be given with reference to FIGS. The same components as those in the conventional example shown in FIGS. 3 and 4 are designated by the same reference numerals.

FIG. 1 shows a first embodiment. In the shield plate 21 of the first embodiment, the tip portion 21a facing the pin 17 of the panel 11 has the pin 17 in the plane including the axis of the cathode ray tube.
Except that the tip 21a is bent so that it comes closer to the pin 17,
It has substantially the same configuration as the conventional example shown in FIGS.

In the first embodiment as described above, since the tip portion 21a is closer to the pin 17 than in the conventional example, the shield plate 2
The area covered by 1 is narrow. Therefore, the adhesion of the Al film 14 can be shielded only in the narrow range of the pin 17 and its surroundings, and the shielding amount can be reduced with a width of about 5 to 10 mm. Therefore, as is clear from the comparison between FIG. 1 and FIG. 3, the carbon 13 and the like can be sufficiently covered,
It is possible to reduce the peeling of the carbon 13 and the like and reduce the withstand voltage failure such as electric discharge.

Moreover, although the tip portion 21a is close to the pin 17, the tip portion 2 is in the plane including the axis of the cathode ray tube.
Since 1a has a convex curved surface with respect to the pin 17, even when the panel 11 main body or the pin 17 comes into contact with the shield plate 21 when the panel 11 is loaded on the vapor deposition pot 15, the tip portion 21a
It is easy for the panel 11 to slide down along the curved surface, and it is difficult for the panel 11 to ride on the shielding plate 21.

FIG. 2 shows a second embodiment. The shield plate 22 of the second embodiment has a groove 23 having a semicircular cross section which is concave with respect to the pin 17 in a plane perpendicular to the axis of the cathode ray tube.
It has substantially the same configuration as that of the first embodiment shown in FIG. 1 except that is provided at the tip portion 22a.

In the second embodiment as described above, since the groove 23 is provided in the tip portion 22a, the panel 11 is attached to the vapor deposition pot 15
Even when the main body of the panel 11 and the pin 17 come into contact with the shield plate 22 when loaded on the top, the panel 17 is likely to slide down along the curved surface of the tip portion 22a while the pin 17 is guided by the groove 23. Therefore, the panel 11 is accurately positioned with respect to the shield plate 22 in the circumferential direction, and the pin 17 and the shield plate 22 face each other accurately.

As a result, the shield plate 22 can shield the adhesion of the Al film 14 only in the pin 17 and the surrounding area thereof, and in the other portions where the phosphor 12 and the carbon 13 are applied. On the other hand, the adhesion of the Al film 14 is not blocked. Therefore, the peeling of carbon 13 etc. is further reduced,
It is possible to further reduce the breakdown voltage failure such as discharge.

In the second embodiment, the groove 23 provided in the tip portion 22a of the shield plate 22 has a semicircular cross section, but a groove having another shape such as a semielliptical shape or a rectangular cross section has a tip. It may be provided in the portion 22a.

[0024]

According to the shield film for forming a metal film of a cathode ray tube of claim 1, the adhesion of the metal film can be shielded by limiting the pin for supporting the color selection mechanism and a narrow range around the pin. As a result, it is possible to sufficiently cover the phosphor, the black non-luminous substance, and the like applied to the inner surface of the panel. Therefore, it is possible to reduce peeling of these phosphors, black non-luminous substances, and the like from the inner surface of the panel, and to reduce breakdown voltage defects such as discharge.

According to a second aspect of the present invention, there is provided a metal film forming shield plate for a cathode ray tube, wherein the frame body and the shield function as a deposition preventing plate for preventing the metal film from adhering to an inner wall surface of the metal film forming apparatus itself. Since it is easy to handle with the plate, the metal film can be efficiently formed.

In the shielding plate for forming a metal film of a cathode ray tube according to a third aspect, the panel is accurately positioned in the circumferential direction with respect to the shielding plate, and the pin for supporting the color selection mechanism and the shielding plate accurately face each other. , It is possible to limit the adhesion of the metal film to the pin and the surrounding area where the phosphor or the black non-luminescent material is not applied, and to the part where the phosphor or the black non-luminescent material is applied. On the other hand, it does not block the adhesion of the metal film. Therefore, it is possible to further reduce the peeling of the phosphor, the black non-luminous substance, and the like from the inner surface of the panel, and further reduce the breakdown voltage failure such as discharge.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part of a first embodiment of the present invention.

FIG. 2 is a perspective view of a main part of a second embodiment of the invention of the present application.

FIG. 3 is a side sectional view of a main part of a conventional example of the invention of the present application.

FIG. 4 is a side sectional view showing a method for forming a metal film.

[Explanation of symbols]

 11 panel 14 Al film 17 pin 19 deposition plate 21 shield plate 21a tip part 22 shield plate 22a tip part 23 groove

Claims (3)

[Claims] 1. A shielding plate for forming a metal film of a cathode ray tube, which is arranged inside the panel when forming a metal film on the inner surface of the panel of the cathode ray tube, for shielding the adhesion of the metal film, wherein: 2. A shield plate for forming a metal film of a cathode ray tube, wherein a tip end portion which should be opposed to a pin for supporting a color selection mechanism provided in is a convex curved surface with respect to this pin. 2. The shielding plate for forming a metal film of a cathode ray tube according to claim 1, wherein the frame body having a plate-shaped peripheral wall is integrated at a base end portion. 3. The shield plate for forming a metal film of a cathode ray tube according to claim 1, wherein a groove concave to the pin is provided on the curved surface.