JP3061233B2 - Cathode ray tube and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube used for a television receiver or the like and a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 10 is a cross-sectional view showing a part of a cathode ray tube disclosed in Japanese Patent Application Laid-Open No. 86033/1996, wherein 1 is a panel screen glass, 2 is a metal frame, and the periphery of the panel screen glass 1 The thick portion 2a sealed by the sealing portion 12 and the sealing portion 23
And a thin portion 2b that forms a part of the side wall and is bonded to the panel screen glass 1 so that the portion 2a is formed with higher rigidity than the portion that is sealed to the funnel glass 3. ing. Reference numeral 4 denotes a fluorescent screen formed on the inner surface of the panel screen glass 1, and reference numeral 5 denotes a metal deposition film formed on the fluorescent screen 4. In the color cathode ray tube, a shadow mask is provided to face the fluorescent screen 4.

Next, the operation will be described. In order to accelerate the electrons drawn from an electron gun (not shown) and irradiate the fluorescent screen 4 with the electrons so as to display an image on the panel screen glass 1 of the cathode ray tube, the panel screen glass 1 of the cathode ray tube and the metal frame As shown in FIG. 11 which is an enlarged view of the vicinity of the joint with the second electrode 2, a high DC voltage of 25 to 30 kv is applied to the fluorescent screen 4 and the metal deposition film 5 formed thereon. On the other hand, the metal frame 2 is set to the ground potential for safety.

The electrons accelerated by the high DC voltage collide with the fluorescent screen 4 and emit fluorescent light. The light emission enters the viewer's eyes directly through the panel screen glass 1. The metal deposition film 5 reflects the light emitted from the fluorescent screen 4 efficiently and emits the light toward the panel screen glass 1.

[0005]

Since the conventional cathode ray tube is constructed as described above, the screen of the panel screen glass 1 is interposed between the fluorescent screen 4 and the metal deposition film 5 and the metal frame 2. Since a high voltage is applied, creeping discharge may occur.

When the creeping discharge occurs, the fluorescent screen 4
Alternatively, the discharge energy concentrates on the discharge location of the metal deposition film 5 and the fluorescent screen 4 or the metal deposition film 5
However, there was a problem that was partially disappeared. Therefore, the creeping insulation distance l shown in FIG.
Needed to be larger. When the creeping insulation distance 1 is increased, there is a problem that the size of the cathode ray tube becomes larger than the size of the fluorescent screen 4.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and can perform high-voltage conditioning of a creeping surface so as to increase the withstand voltage of the creeping surface. It is an object of the present invention to obtain a cathode ray tube and a manufacturing method suitable for the cathode ray tube.

[0008]

According to the present invention, there is provided a cathode ray tube in which a part of a vacuum envelope is formed of a metal frame, and a panel screen glass is sealed to an end of the metal frame. In the tube, a metal frame is provided on an outer periphery of an end portion of a fluorescent screen and a metal deposition film formed on an inner surface of a panel screen glass.

Further, a metal shielding plate is provided between the metal frame and the metal frame for shielding the inner wall of the panel screen glass from irradiating electrons.

Further, the present invention relates to a method for manufacturing a cathode ray tube wherein a part of a vacuum envelope is formed of a metal frame and a panel screen glass is sealed to an end of the metal frame. After joining the metal frame to the outer peripheral position of the inner surface of the panel screen glass where the fluorescent screen and the metal vapor-deposited film are formed, the fluorescent screen and the metal vapor-deposited film are formed with the metal frame as the outer end. is there.

Further, the present invention relates to a method for manufacturing a cathode ray tube, wherein a part of a vacuum envelope is constituted by a metal frame, and a panel screen glass is sealed to an end of the metal frame. After a fluorescent screen and a metallized film are formed on the inner surface of the panel screen glass, a metal frame is bonded to the outer periphery of the ends of the fluorescent screen and the metallized film.

[0012]

The cathode ray tube according to the present invention can perform high-voltage conditioning on the surface between the metal frame and the metal frame. In addition, the metal shield plate can prevent the inner wall of the panel screen glass from being irradiated with electrons, and further, high voltage conditioning can be performed between the metal shield plate and the metal frame or the metal frame.

[0013]

【Example】

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 6 denotes a metal frame provided on the outer periphery of the fluorescent screen 4 and the metal deposition film 5, which is fused to the panel screen glass 1 by a fusion portion 16. Metal frame 6
In order to fuse with the panel screen glass 1, Kovar metal, surface-oxidized stainless steel, or the like is used. Other configurations are the same as those in FIGS. 10 and 11, and the same portions are denoted by the same reference numerals and description thereof will be omitted.

FIG. 2 shows a manufacturing process of the cathode ray tube. First, the metal frame 6 is fused to the panel screen glass 1. The fluorescent screen 4 is placed inside the fused metal frame 6.
Is formed, a metal deposition film 5 is deposited. Thereafter, the metal frame 2 and the panel screen glass 1 are sealed with the sealing portion 12.

When a high voltage is applied to the cathode ray tube configured as described above, even if a creeping discharge along the surface of the panel screen glass 1 occurs between the metal frame 2 and the metal frame 6, this creepage occurs. Discharge is limited between the metal frame 2 and the metal frame 6,
Since it does not reach the fluorescent screen 4 or the metal deposition film 5,
Part of the fluorescent screen 4 or the metal deposition film 5 does not disappear due to the discharge.

Further, in the manufacturing process, conditioning is performed by applying a high voltage in a vacuum state in advance.
Weak points of insulation between the metal frame 2 and the metal frame 6 can also be removed. Therefore, the creepage insulation distance on the panel screen glass 1 can be shortened.

Embodiment 2 FIG. In the above embodiment, the metal frame 6 is fused to the panel screen glass 1 at the fusion portion 16. However, as shown in FIG. 3, the metal frame 6 is bonded to the panel screen glass 1 by frit glass 7. You may join. At this time, carbon steel or the like can be used as the material of the metal frame 6.

Embodiment 3 FIG. Further, as shown in FIG. 4, the metal frame 6 and the panel screen glass 1 may be bonded with an inorganic adhesive 8 that generates little gas in a vacuum.

Embodiment 4 FIG. In the above embodiment, the fluorescent screen 4 and the metal deposition film 5 were formed after the metal frame 6 was provided on the panel screen glass 1, but as shown in FIG.
After forming the fluorescent screen 4 and the metal deposition film 5 on the panel screen glass 1, the metal frame 6 may be bonded with an inorganic adhesive. In this case, it is natural that conduction between the metal frame 6 and the metal deposition film 5 is kept.

Embodiment 5 FIG. Further, in the above embodiment, the surface of the panel screen glass 1 between the metal frame 2 and the metal frame 6 is irradiated with accelerated electrons drawn from the electron gun. The creeping dielectric strength under such electron irradiation is lower as shown in FIG. 6 than the vacuum creeping dielectric strength without electron irradiation.

For this reason, as shown in FIG.
Then, a metal shielding plate 9 is attached so as to cover the surface of the panel screen glass 1 and the metal frame 6 so that electrons do not irradiate the panel screen glass 1. The metal shielding plate 9 is attached to the metal frame 2 by welding or screwing, or is formed integrally with the metal frame 2.

Embodiment 6 FIG. In the fifth embodiment, an example in which the metal shielding plate 9 is attached to the metal frame 2 has been described.
, A metal shielding plate 9 may be attached to the metal frame 6 so as to cover the periphery of the panel screen glass 1 and the metal frame 2.

Embodiment 7 FIG. Further, the first to sixth embodiments can also be applied to, for example, a flat-plate cathode ray tube disclosed in JP-A-253144. FIG. 9 shows an example thereof, 21 is a cathode portion as an electron beam source, 22 is an electron beam extraction means for extracting an electron beam from the cathode portion 21, and 23 is an electrode group for controlling the electron beam extracted therefrom. . Other configurations are the same as those in FIG.

[0024]

As described above, according to the present invention, since the metal frame is provided on the outer periphery of the fluorescent screen and the metal deposition film, high-voltage conditioning on the surface of the panel screen glass can be performed. In addition, the metal shielding plate can prevent the panel screen glass from being irradiated with electrons.
High voltage conditioning can be performed between the metal shielding plate and the metal frame or metal frame. Since the weak point of the insulation can be removed by these high-voltage conditioning, there is an effect that a compact cathode ray tube having high insulation performance can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing a main part of a cathode ray tube according to Embodiment 1 of the present invention.

FIG. 2 is a flowchart showing an example of a procedure for manufacturing a cathode ray tube according to the present invention.

FIG. 3 is a sectional side view showing a main part of a cathode ray tube according to Embodiment 2 of the present invention.

FIG. 4 is a sectional side view showing a main part of a cathode ray tube according to Embodiment 3 of the present invention.

FIG. 5 is a flowchart showing a procedure for manufacturing a cathode ray tube according to Embodiment 4 of the present invention.

FIG. 6 is a diagram showing a vacuum creepage withstand voltage characteristic depending on the presence or absence of electron irradiation.

FIG. 7 is a sectional side view showing a main part of a cathode ray tube according to Embodiment 5 of the present invention.

FIG. 8 is a sectional side view showing a main part of a cathode ray tube according to Embodiment 6 of the present invention.

FIG. 9 is a sectional side view showing a main part of a cathode ray tube according to a seventh embodiment of the present invention.

FIG. 10 is a sectional side view showing a main part of a conventional cathode ray tube.

FIG. 11 is a sectional side view showing a voltage application state of a conventional cathode ray tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel screen glass 2 Metal frame 4 Fluorescent screen 5 Metal deposition film 6 Metal frame 7 Frit glass 8 Inorganic adhesive 9 Metal shielding plate 12 Sealing part 16 Fusion part

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-6748 (JP, A) JP-A-4-366536 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 29/28 H01J 9/22

Claims (5)

(57) [Claims] 1. A part of a vacuum envelope is formed of a metal frame,
In a cathode ray tube configured to seal a panel screen glass to an end of the metal frame, a metal frame is provided on an outer periphery of an end of a fluorescent screen and a metal deposition film formed on an inner surface of the panel screen glass. A cathode ray tube. 2. The cathode ray tube according to claim 1, wherein a metal shielding plate is provided on the metal frame to shield the inner wall of the panel screen glass from electron irradiation between the metal frame and the metal frame. . 3. The cathode ray tube according to claim 1, wherein a metal shielding plate for shielding the inner wall of the panel screen glass from electron irradiation between the metal frame and the metal frame is provided on the metal frame. 4. A part of the vacuum envelope is formed of a metal frame,
In a method for manufacturing a cathode ray tube configured to seal a panel screen glass to an end of the metal frame,
After joining the metal frame to the outer peripheral position of the end portion where the fluorescent screen and the metal deposition film are formed on the inner surface of the panel screen glass, the fluorescent screen and the metal deposition film are formed with the metal frame as the outer end. Characteristic method for manufacturing a cathode ray tube. 5. A part of the vacuum envelope is formed of a metal frame,
In a method for manufacturing a cathode ray tube configured to seal a panel screen glass to an end of the metal frame,
A method for manufacturing a cathode ray tube, comprising: forming a fluorescent screen and a metal deposition film on an inner surface of the panel screen glass; and bonding a metal frame to an outer periphery of an end portion of the fluorescent screen and the metal deposition film.