JPH04118839A - Color cathode-ray - Google Patents

Abstract

PURPOSE:To cause an elastic support member to be fitted and retained always at the same position and thereby obtain good reproducibility with respect even to repeated attachments/detachments, by providing chromium-oxide based composite ceramic layers on the fitting hole for the elastic support member and around this fitting hole respectively. CONSTITUTION:By forming a chromium-oxide based composite ceramic layer 38 on a fitting hole 38 for an elastic support member 33, the friction resistance when the elastic support member 33 is fitted over and retained by a stud pin 32 can be made remarkably small. In addition, owing to its high hardness and anti-consumability, it is possible to prevent positional deviation between the stud pin 32 and the elastic support member 33 conventionally taking place due to the surface roughness of the stud pin 32 covered with an oxidized film. In particular, a composite ceramic layer 39 around the fitting hole 38 reinforces the bond strength of the layer 39 formed on the fitting hole 38 and hence the layer 39 is difficultly peeled off. Thus, the positional deviation of a shadow mask is prevented from occurring against a plurality of attachments/detachments thereof in the process of manufacturing a color Braun tube, whereby the shadow mask 26 can be mounted always at the same position.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a color cathode ray tube, and more particularly to a color cathode ray tube in which a shadow mask is supported inside the panel in a removable manner and with good reproducibility. .

(Prior art) In general, a color cathode ray tube has a phosphor screen formed on the inner surface of the panel of the envelope, which is composed of three-color phosphor layers that emit blue, green, and red light, and a large number of electron beams pass through the inside of the phosphor screen. A shadow mask with holes is arranged, and the three electron beams emitted from the electron gun are deflected by the magnetic field generated by the deflection yoke, and then the phosphor screen is horizontally and vertically scanned through the shadow mask. It is formed in a structure that displays a color image on a phosphor screen.

Originally, the above-mentioned shadow mask was made up of three particles emitted from an electron gun.
The purpose is to select the electron beam so that it will land correctly on the three-color phosphor layer. Therefore, the three-color phosphor layer and the shadow mask need to be arranged in a matching relationship.

Incidentally, the phosphor screen of the color cathode ray tube is formed by assembling a panel-mask assembly by combining a panel and a shadow mask in a predetermined relationship, and then forming the panel-mask assembly by a photoprinting method.

That is, as shown in FIG. 4(a), the shadow mask is removed from the panel/mask assembly and the panel (1
) After coating the inner surface with a phosphor slurry layer (2) containing a phosphor and a photosensitizer as main components, the removed shadow mask was attached to the panel (1), as shown in (b). The phosphor slurry layer (2) is exposed from an exposure light source (not shown) through the shadow mask (3) to print a pattern corresponding to the electron beam passage hole (4) of the shadow mask (3). . Thereafter, the shadow mask (3) is removed from the panel (1), and the phosphor slurry layer (2) is baked with a pattern corresponding to the electron beam passage hole.
) is developed to remove unexposed areas, and as shown in (e), a phosphor layer (5) is formed. By repeating this phosphor layer formation method for three color phosphors, three color phosphor layers (5B), (5G), (
5R). The phosphor screen thus formed is then further vacuum-deposited with an aluminum film (6) on the three-color phosphor layers (5B), (5G), <5R), as shown in (e). It is formed by

The panel on which the phosphor screen is formed is then attached with the shadow mask, and then integrally joined with the funnel, and the electron gun is further sealed and evacuated to form a color cathode ray tube.

Therefore, - the shadow mask is attached and detached multiple times after the panel-mask combination is assembled and before it is installed in the tube. Therefore, as shown in Fig. 5, the shadow mask has a structure that makes it easy to attach and detach from the panel and that it is always correctly attached even after repeated attachment and detachment. ), while
Attach these multiple stud pins (7) to the shadow mask (8).
) by attaching a plurality of elastic supports (8) corresponding to each other, and fitting and locking the fitting hole formed at the tip of each elastic support (8) to each stud pin (7). Panel (1
) It is structured so that it can be detachably attached to the inside.

Such a stud pin (7) and an elastic support (8)
In particular, the stud pins (7) attached to the panel (1) are made of a stainless steel material with a thermal expansion coefficient similar to that of the glass constituting the panel (1), and have a surface with a thickness of about 10μ. An oxide film is formed. This oxide film improves compatibility with the glass, increases the strength of its installation, and also serves to prevent the stud pin (7) from rusting. Therefore, this oxide film is an important component of the stud pin as a mask support means, but as can be seen from the curve (lO) in FIG. ~6
There are micrometer-sized unevenness.

Therefore, as shown in Figure 7, this stud pin (7
) When attempting to fit and lock the elastic support (8) attached to the shadow mask, due to the frictional resistance based on the surface roughness, it will not fit properly as shown by the solid line, but as shown by the broken line. It may not fit and lock in the same position. This misalignment of the elastic support (8) with respect to the stud pin (7) occurs not only when the three-color phosphor layer is formed, but also with the shadow mask attached after the phosphor screen is formed, and as a result, the three-color phosphor layer The landing of the electron beam on the three-color phosphor layer is shifted, making it difficult to adjust the color purity, and when the shift exceeds the landing margin of the three-color phosphor layer, color shift occurs, deteriorating the image quality.

(Problem to be solved by the invention) As mentioned above, the shadow mask of a color cathode ray tube is
It is used to select the three electron beams emitted from the electron gun so that they land correctly on the three-color phosphor layer, and for this purpose, the three-color phosphor layer and each electron beam passage hole of the shadow mask are in a matching relationship. must be placed in On the other hand, the shadow mask is attached and detached multiple times during the manufacturing process of color cathode ray tubes, from when the panel/mask assembly is assembled until it is installed inside the tube. Therefore, the shadow mask has a plurality of stud pins attached to the panel so as to always satisfy the alignment relationship even when the shadow mask is attached and detached multiple times, and a plurality of elastic supports are attached to the shadow mask corresponding to the stud pins. The structure is such that it can be removably attached to the inside of the panel by fitting and locking the fitting hole formed at the tip of each elastic support to each stud pin.

However, conventional stud pins are made of stainless steel material whose coefficient of thermal expansion is similar to that of the glass that makes up the panel, so that they fit well with the glass that makes up the panel, increase the strength of the installation, and protect the stud pin. An oxide film about 10μ thick is formed on the surface, which also serves as rust. This oxide film is an important component of the stud pin as a mask support means, but since the surface roughness is large, the elastic support attached to the shadow mask is fitted onto the stud pin on which this oxide film is formed. When trying to fit and lock them, they may not fit and lock at the same position due to frictional resistance based on the surface roughness. Therefore, if the position of the three-color phosphor layer shifts, or if the position of the shadow mask attached after forming the phosphor screen shifts, the landing of the electron beam on the three-color phosphor layer will shift, making it difficult to adjust the color purity. However, if the deviation exceeds the landing margin of the three-color phosphor layer, a problem arises in that color deviation occurs and image quality deteriorates.

This invention was made to solve the above problem, and even if the shadow mask is repeatedly attached and detached from the panel, the elastic support body attached to the shadow mask is always fitted in the same position with respect to the stud pin. The purpose is to provide a structure that allows good reproducibility to be obtained by fitting and locking.

[Structure of the Invention] (Means for Solving the Problems) A shadow mask in which a large number of electron beam passage holes are formed is disposed inside a panel having a skirt portion at its periphery, and this shadow mask is connected to the skirt of the panel. The shadow mask is removably supported by a mask support means consisting of a plurality of stud pins fixed to the inner surface of the shadow mask, and an elastic support member fixed to the shadow mask and having a fitting hole that fits and locks the stud pins. In this color cathode ray tube, a composite ceramic layer based on chromium oxide was provided in the fitting hole of the elastic support and around the fitting hole.

(Function) As described above, if a composite ceramic layer based on chromium oxide is provided around the fitting hole of the elastic support that fits and locks the stud pin, and the composite ceramic layer is formed around the fitting hole, the composite ceramic layer The frictional resistance with the pin can be reduced, and the high hardness and wear resistance of the composite ceramic layer can improve the reproducibility of fitting and locking with the stud pin. Moreover, since the elastic support has a simple structural shape, the composite ceramic layer can be formed relatively easily.

(Example) Hereinafter, the present invention will be described based on an example with reference to the drawings.

FIG. 1 shows a color cathode ray tube, which is one embodiment of the present invention.

This color cathode ray tube has a skirt section (20) on the periphery.
A glass panel (21) formed with a glass panel (21) and a funnel-shaped funnel (22) integrally joined to this panel (21).
), and on the inner surface of the panel (21),
A phosphor screen (2
3) is formed, and facing this phosphor screen (23), there is a mask body (24) with a large number of electron beam passage holes formed inside it, and a mask frame ( A shadow mask (26) consisting of 25) is attached by the following mask support means. Also, three electron beams (2) are placed in the neck (27) of the funnel (22).
An electron gun (29) that emits 8B), (28G), and (28R) is provided. And this electron gun (
3 electron beams (28B) emitted from 29).

(28G) and (28R) are deflected by a magnetic field generated by a deflection yoke (30) attached to the outside of the funnel (22), and the phosphor screen (23) is horizontally and vertically scanned. (23) It is formed in a structure to display a color image thereon.

The mask supporting means includes a plurality of stud pins (3) fixed to the inner surface of the skirt portion (20) of the panel (21).
2), and an elastic support (33) fixed to the outer surface of the mask frame (25) in correspondence with each stud pin (32).

Each stud pin (32) is made of a stainless steel material with a coefficient of thermal expansion similar to that of glass constituting the panel (21), and as shown in FIG. The support body (33) is formed into a stepped cylindrical shape consisting of a tapered locking part (3B) that fits and locks,
On its surface, an oxide film (approximately 10 μl thick) is coated to improve compatibility with the glass that constitutes the panel (21).
37) is formed. For this stud pin (32), an elastic support member 33) is attached as shown in FIG.
Made of stainless steel material that is bent into a double-shaped band shape and has a fitting hole (38) formed at its tip to fit and lock into the locking part (3B) of the stud pin (32). Become.

Furthermore, the elastic support (33) of this example has a fitting hole (
38) and a composite ceramic layer (39) based on chromium oxide is provided around this fitting hole (38).

And the shadow mask (26) is formed by this elastic support (
It is removably attached to the inside of the panel (21) by fitting and locking the fitting hole (38) formed at the tip of the panel (33) into the corresponding stud pin (32).

The elastic support (33) is formed into a predetermined shape by press molding, and a fitting hole (38) is formed in the predetermined portion of the elastic support (33). (manufactured by our company),
A composite ceramic layer (39
) can be obtained by forming

By the way, as mentioned above, the fitting hole (
When a composite ceramic layer (39) based on chromium oxide is formed on 3B), this composite ceramic layer (39) reduces the frictional resistance when fitting and locking the elastic support (33) to the stud pin (32). It can be made significantly smaller. In addition, this composite ceramic layer (39) has high hardness and wear resistance, so it acts as an elastic support for the stud pin (32), which has conventionally been covered with an oxide film due to the surface roughness of the stud pin (32). 33) can be prevented from shifting. In particular, the composite ceramic layer (39) around the fitting hole (38) reinforces the adhesive strength of the composite ceramic layer (39) formed in the fitting hole (38) and prevents it from peeling off. Therefore, as described above, a composite ceramic layer (39) based on chromium oxide is formed in the fitting hole (38) of the elastic support (33) and around it.
By forming the shadow mask (2B), it is possible to prevent the shadow mask (2B) from shifting its position even when the shadow mask (2B) is attached and detached several times during the color cathode ray tube manufacturing process, and the shadow mask (26B) is always kept at the same position.
), the color purity can be easily adjusted and a color cathode ray tube with good brown color purity can be constructed.

In addition, there is an earlier application of this invention in which a similar composite ceramic layer is formed on a stud pin, but when forming a composite ceramic layer on a stud pin as in this earlier application, the stud pin is attached to the glass that constitutes the panel. In order to ensure strength, it is necessary to form an oxide film at least on the part where the stud pin is embedded in the panel, and to form a composite ceramic layer on the part where it locks with the elastic support. However, if the composite ceramic layer (39) is formed on the elastic support (33) as in this example, it is only necessary to form an oxide film on the stud pin (32). 39) can be formed directly on the metal surface of the elastic support (33), which has the advantage that the manufacturing process is not complicated.

[Effects of the Invention] A mask support means comprising a stud pin fixed to the inner surface of the skirt portion of the panel and an elastic support fixed to the shadow mask and having a fitting hole that fits and locks with the stud pin. If a composite ceramic layer based on chromium oxide is provided in the fitting hole of the elastic support and around it, the frictional resistance when the elastic support is engaged and locked with the stud pin is reduced by the composite ceramic layer. 1, and the high hardness and abrasion resistance of the composite ceramic layer improves the position reproducibility of the elastic support relative to the stud pin, making it easy to attach and detach the shadow mask multiple times during the manufacturing process of color cathode ray tubes. A shadow mask can be always mounted at the same position by preventing positional shift, and a color cathode ray tube with good brown color purity can be constructed with easy adjustment of color purity.

[Brief explanation of the drawing]

Fig. 1 shows the structure of a color cathode ray tube which is an embodiment of the present invention, Fig. 2 shows the structure of its stud pin, Fig. 3 shows the structure of its elastic support, and Fig. 4 (
a) to <e> are diagrams for explaining the method of forming a phosphor screen of a color cathode ray tube, respectively, and FIGS. 5(a) and (b)
) are a plan view and a cross-sectional view respectively showing the support means for the shadow mask to the panel, FIG. 6 is a diagram showing the surface roughness of the locking part of a conventional stud pin, and FIG. 7 is a diagram showing the elastic support for the stud pin. FIG. 6 is a diagram for explaining a fitted and locked state. 20...Skirt part 21...Panel 24...
・Mask body 25...Mask frame 26...
・Shadow mask 32...Stud pin 33...
Elastic support body 37...Oxide film 38...Fitting hole 39...Composite ceramic layer agent Patent attorney Noriyoshi Ogo Diagram °0 Φ

Claims (1)

[Claims] A shadow mask having a large number of electron beam passing holes is disposed inside a panel having a skirt portion on the periphery, and this shadow mask has a plurality of shadow masks fixed to the inner surface of the skirt portion of the panel. In the color cathode ray tube detachably supported by a mask support means consisting of stud pins and an elastic support fixed to the shadow mask and having a fitting hole that fits and locks with the stud pin, A color cathode ray tube characterized in that a fitting hole of an elastic support and a composite ceramic layer based on chromium oxide are provided around the fitting hole.