JP2002170498A - Color cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-neck color cathode-ray tube that can solve insufficient brightness and color shifting by absorbing and controlling the vibration of the shadow mask in such an tensioned shadow mask tensioning a mask frame by applying tension on a shadow mask that vibration of shadow mask caused by external vibration generates the displacement between a hole of the shadow mask and a phosphor layer of a phosphor screen. SOLUTION: A mask frame comprises first arm materials 23 and second arm materials 24. A shadow mask 16 is tensioned between the first arm materials 23. A vibration preventive plate 26 is attached between the first arm materials 23 corresponding to non-scanning parts of electron beams 15 by plural electron guns 18 with contacting with or putting close to the shadow mask 16. Thus, the vibration is absorbed and controlled by the vibration preventive plate 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-neck type color picture tube provided with a plurality of necks (electron guns) for preventing vibration of a shadow mask stretched and stretched on a mask frame.

[0002]

2. Description of the Related Art At present, a color picture tube generally used for a color television receiver, a color terminal display and the like includes a face panel 71 having a substantially rectangular screen as shown in FIG. An envelope having a funnel 72 integrally joined to the face panel 71 is provided, and red, green,
Phosphor screen 7 having a three-color phosphor layer that emits blue light
3 are formed.

In the envelope, a shadow mask 75 for color selection by passing an electron beam 74 is provided on the inner surface of the face panel 71 via a mask frame 76 in opposition to the phosphor screen 73. Has been attached.

An electron gun 78 for emitting an electron beam 74 is provided in a neck 77 of the funnel 72. The electron beam 74 emitted from the electron gun 78 is provided.
A deflection yoke 79 mounted outside the funnel 72.
The electron beam 74 scans the phosphor screen 73 in the horizontal and vertical directions, thereby reproducing a color image on the phosphor screen 73.

Further, a reinforcing band 80 is fitted and attached to the outer peripheral surface of the face plate 71, and one end of the reinforcing band 80 is fixed to the mask frame 76,
On the other side, a magnetic shield plate 81 extending along the inner wall of the funnel 72 is attached to constitute a color picture tube.

In recent years, the demand for flattening the color picture tube has been increasing from the viewpoint of easy viewing as the color picture tube becomes larger and larger in size. Tubes also require higher resolution in addition to this.

In order to improve the resolution, it is necessary to reduce the pitch of the apertures of the shadow mask 75 to achieve higher definition. However, since the apertures of the shadow mask 75 are generally formed by etching. Considering this etching process, it is more efficient that the thickness of the shadow mask 75 is smaller.

On the other hand, from the viewpoint of the mechanical strength of the shadow mask 75, it is more advantageous to use a thicker one. Therefore, in order to achieve high definition, it is necessary to clear such conflicting conditions. There is.

From such a point, there has been proposed a stretching system in which tension is applied to a flat shadow mask 75 having a relatively small thickness to hold the shadow mask 75 on a mask frame 76. In each of these methods, in a state in which sufficient tension is applied to a flat shadow mask 75 having a large number of openings, at least both the upper and lower ends of the shadow mask 75 are fixedly held to the mask frame 76. Is adopted.

As a method of applying the tension, various methods have been considered. One of the methods is, for example, a shadow mask formed in a fine line slit shape as disclosed in Japanese Patent Application Laid-Open No. 609225. 75, a mask fixing piece (not shown) is attached to both ends of a mask frame 76 having elasticity in the vertical vertical off-axis direction, and is fixed to this mask fixing piece, so that the shadow mask 75 Some have applied vertical tension.

The mask frame 76 used in this method
Are formed in a frame shape as a whole, but a pair of first arm members (beam members) of the two pairs which are spaced apart and opposed to each other are fixed to a mask for welding and holding the shadow mask 75. As a piece, the second arm member is formed from a plate material having an L-shaped cross-section, and the other second arm member is a bar member having a square cross-section arranged so as to be orthogonal to the vicinity of an end of the first arm member. Or it is composed of square-shaped plate material,
The first and second arm members are welded and fixed at their ends to form a frame-shaped mask frame 76 as a whole.

With such a configuration, the shadow mask 75 in the form of a thin line slit does not have a connection in the horizontal direction. There is an advantage that a mask surface with high surface accuracy can be obtained because it can be applied and a pressing step is not required for forming the mask surface.

A method of using a shadow mask 75 having a horizontal connection in which a large number of openings are formed in a thin metal plate without using such a thin line slit-shaped shadow mask 75 has also been adopted. I have.

That is, as shown in FIG. 11, a pair of first first metal members are vertically spaced apart from each other in a hollow, triangular section formed by forming a metal plate by a method such as roll forming.
And a pair of second arm members 83 that are welded and fixed to the end of the first arm member 82 and are spaced apart from each other in the horizontal direction to form a rectangular mask frame 76. Constitute.

The first and second arm members 82, 83
The elastic support members 8 which engage with stud pins (not shown) provided on the face panel 71
4 is fixed by spot welding.

On such a mask frame 76, a shadow mask 75 having a large number of rectangular or round openings 85 in a flat, thin rectangular metal plate is welded and fixed by a stretching method. ing. The stretching of the shadow mask 75 with respect to the mask frame 76 is performed by pressing the first arm members 82 of the mask frame 76 so as to approach each other to compress the mask frame 76, and to move the shadow mask 75 in the vertical axis direction. With the tension applied to the shadow mask 75 in this state, the end of the shadow mask 75 is welded to the first arm member 82, and then the respective loads of the mask frame 76 and the shadow mask 75 are removed, whereby the shadow mask 75 is removed. It is stretched and stretched on the mask frame 76.

Therefore, in a limited space which does not obstruct the trajectory of the electron beam 74, a section modulus required for a stress applied to the mask frame 76 is provided.
Is designed such that the weight of the entire mask frame 76 is reduced by using a bent or welded plate material or a hollow member.

However, the shadow mask 75 attached to the mask frame 76 by such a stretching method is used.
When one end receives external vibration due to a shock from a speaker of a television receiver or the outside, a resonance phenomenon occurs and the vibration is continued, and the vibration is continued.
The arrangement relationship between the phosphor layer and the opening 85 of the shadow mask 75 is shifted, and the displayed image is partially darkened.
This was the cause of color shift.

[0019]

As described above, since the shadow mask 75 of the stretch-stretched type is formed particularly thin, the shadow mask 75 itself is much more difficult than the shadow mask 75 of the press molding type. It is easy to vibrate. When the shadow mask 75 starts to vibrate, the positional relationship between the opening 85 of the shadow mask 75 and the phosphor layer of the phosphor screen 73 is shifted, so that the electron beam 74 does not strike the target phosphor layer. Due to this, the display image is partially darkened due to lack of luminance, or in the worst case, hits a phosphor layer of another color which is unintended, developing into a so-called other color hitting phenomenon, causing color misregistration. There was a risk.

In order to suppress such a vibration of the shadow mask 75, as shown in, for example, JP-A-8-227667, an anti-vibration wire made of a thin metal wire is erected along the shadow mask 75. A method has been considered in which the vibration is rapidly attenuated by disturbing the resonance, for example, by disposing a metal rod on the non-perforated surface of the shadow mask 75.

However, with the high definition of the color picture tube, even if the vibration of the shadow mask 75 is slight,
The color shift on the screen has become clearly visible, and the shadow mask 75 has become easier to vibrate than ever as the screen becomes larger.

Therefore, the vibration-proofing method using such a vibration-proofing wire or a metal rod cannot provide a sufficient vibration-proofing effect, and there has been a demand for a color picture tube having a larger attenuation effect.

The present invention is particularly effective for a multi-neck type color picture tube using a shadow mask adopting a stretching system, and even when excitation is applied from the outside, the vibration is immediately suppressed without resonance. Absorb,
It is an object of the present invention to provide a color picture tube in which vibration of a shadow mask is prevented and luminance fluctuation or color shift of a screen is prevented.

[0024]

SUMMARY OF THE INVENTION The present invention is directed to a rectangular face panel having a phosphor screen on an inner surface, a funnel-shaped funnel connected to the face panel and having a plurality of necks, and disposed in the face panel. A shadow mask that faces the phosphor screen at a predetermined distance, a plurality of electron guns housed in each neck that emits an electron beam that scans a predetermined portion of the phosphor screen through the shadow mask, and a shadow mask. A color picture tube having a mask frame that stretches and holds a mask and a vibration isolator placed in contact with or close to the shadow mask, wherein the vibration of the shadow mask is suppressed by the vibration isolator It is.

As described above, by attaching the vibration isolating plate in contact with or close to the shadow mask, the vibration is attenuated by the contact friction between the shadow mask and the vibration isolating plate, and the multi-neck type is enlarged. Even when a shadow mask corresponding to the phosphor screen is used, it is possible to provide a color picture tube with little color fluctuation and little color shift and improved color purity.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a multi-neck type color picture tube having two necks, and FIG. 2 is a perspective view thereof. That is, a face panel 11 having a substantially rectangular screen and a funnel-shaped funnel 13 integrally joined to the face panel 11 and provided with two necks 12 are provided.
The face panel 11 is provided with an envelope having
A phosphor screen 14 having a three-color phosphor layer that emits red, green, and blue light is formed on the inner surface.

Further, inside the envelope, a shadow mask 16 through which an electron beam 15 passes to perform color selection and a mask frame 17 on the inner surface of the face panel 11 face the phosphor screen 14. Has been attached through.

Further, each of the two necks 1 of the funnel 13
An electron gun 18 for emitting an electron beam 15 is disposed in each of the electron guns 2, and the electron beam 15 emitted from the electron gun 18 is attached to the outside of a funnel 13 corresponding to each neck 12. Each of the electron guns is deflected by a magnetic field generated by a corresponding one of the deflection yokes 19 and scans the phosphor screen 14 in the horizontal and vertical directions with an electron beam 15, as shown in FIG. 18
2 reproduces and displays individual color images a and b, and reproduces and displays a single color image as a whole screen with the individual color images a and b or separate images with the individual color images a and b. It has a screen configuration.

The mask frame 17 is mounted in the face panel 11 by four elastic supports 22 spot-welded to the mask frame 17 on four stud pins 21 fixed to the inner surface of the skirt 20 of the face panel 11. Locked.

As shown in FIG. 4, the mask frame 17 is formed by hollowing a metal plate for holding the shadow mask 16 by welding so as to have a triangular cross section, and is opposed to and spaced apart in the vertical direction. And a pair of first arm members (beam members) 23, which are disposed so as to be orthogonal to the ends of the first arm members 23, and similarly, the metal plate is formed in a hollow shape so as to have a triangular cross section. It has a pair of second arm members 24 that are formed and are horizontally opposed to each other and are spaced apart from each other. The first and second arm members 23 and 24 are welded and fixed at their ends, and have a rectangular shape as a whole. The frame is formed.

The second arm member 24 regulates the interval between the first arm members 23 so as to be a predetermined interval, and has a role of applying tension to the shadow mask 16.

The mask frame 17 thus configured
A flat and substantially rectangular shadow mask 16 having a large number of rectangular or round holes 25 is welded and fixed to a flat and thin rectangular metal plate by a stretching method. The long side is parallel to the horizontal axis and the short side is parallel to the vertical axis.

The mask frame 17 is compressed in advance by pressing the first arm members 23 so as to approach each other in the vertical axis direction, and the shadow mask 16 is previously tensioned in the vertical axis direction. And add
In this state, the shadow mask 16 of the first arm member 23 is
The shadow mask 16 can be stretched on the mask frame 17 by welding the ends of the shadow mask 16 to the attachment portion and removing the loads of the mask frame 17 and the shadow mask 16 after welding.

A long plate-shaped vibration isolator 26 is provided between the first arm members 23 in contact with or close to the shadow mask 16. The anti-vibration plate 26 is made of, for example, the same material as the second arm member 24, and is formed of a U-shaped plate having both ends bent at right angles.

The vibration isolating plate 26 is provided between the pair of first arm members 23, and the bent portions 27 provided at both ends thereof are fixed to the first arm member 23 by spot welding. After the shadow mask 16 is stretched and stretched, as shown in FIG. 5 cut in the XX line direction in the figure, the vibration isolating plate 26 is disposed outside the shadow mask 16 between the pair of first arm members 23. That is, it is installed on the phosphor screen 14 so as to straddle the first arm member 23 in contact with or close to the shadow mask 16 and to be located in the non-scanning portion of both electron beams 15.

For this reason, for reproducing a regular image,
It is preferable from the viewpoint of the anti-vibration effect that the electron beam 15 is formed as wide as possible so as not to hinder the scanning of the electron beam 15 with respect to the ordinary phosphor screen 14. 15 collides with each other and a shadow which becomes a non-light emitting portion is generated on the phosphor screen 14, so that it is desirable to set the plate width A of the vibration isolator 26 as follows.

That is, as shown in FIG. 6, the horizontal length of the phosphor screen 14 is H, the distance from the center of the phosphor screen 14 to the deflection center of each electron gun 18 is Lo, and the phosphor screen 14 Is the distance between the phosphor screen 14 and the shadow mask 16 at the center of q. Further, when the pitch of the openings 25 of the shadow mask 16 is P, the relationship is set so as to satisfy the relationship of P ≦ A <(H × q) / (2 × Lo).

By selecting the width A of the vibration isolating plate 26 so as to satisfy this condition, the scanning of the electron beam 15 for reproducing an image on the phosphor screen 14 is not affected, and It is possible to reliably exhibit the anti-vibration effect.

Of course, it does not matter if this condition is not met, but the point is that both electron beams 15 are not affected so that the scanning electron beam 15 emitted from each electron gun 18 does not hinder the screen scanning. There is no problem if the vibration isolator 26 is arranged in the scanning area.

Therefore, when the shadow mask 16 is vibrated in an out-of-plane direction by excitation of a speaker, external shock vibration, or the like, the shadow mask 1 is moved by the vibration isolating plate 26.
6, the vibration isolator 26 and the shadow mask 16 come into contact with each other in a wide area, and the two slide in response to the vibration. A frictional operation occurs on the contact surface of the shadow mask 16, and the frictional energy promptly converts the vibration energy into heat energy, so that the vibration is suppressed in a short time.

When the vibration isolator 26 is disposed outside the shadow mask 16 as described above, the shadow mask 1
6, the bent portion 27 of the vibration isolator 26 is simply welded to the first arm member 23 so that the structure can be simplified.

Thus, the vibration is suppressed from being absorbed.
The vibration isolator 26 can be attached in addition to the configuration shown in FIGS. 4 and 5, for example, as shown in FIGS. 7 and 8. The configuration shown in FIG. 7 shows a case where the vibration isolator 26 is arranged inside the shadow mask 16, that is, on the side of the electron gun 18, similarly to the configuration shown in FIG. 5. In this case, the plate width A of the vibration isolator 26 can be increased, though slightly, since the shadow mask 16 can be disposed in a wide portion of the non-scanning portion of the electron beam 15.

On the other hand, in the case of FIG.
Are arranged on both sides of the shadow mask 16 so that the shadow mask 16 is sandwiched by the vibration isolating plates 26. Thus, the vibration isolating plates 26 are provided on both sides of the shadow mask 16.
Is arranged, it becomes easier to more effectively absorb the vibration.

The phosphor screen 14 which is located outside the shadow mask 16 in accordance with the scanning range of the electron beam 15 with respect to the width A of the vibration isolating plate 26 located on the electron gun 18 side inside the shadow mask 16. Width A of the vibration isolator 26 on the side
Is small, the width A of the vibration isolator 26 can be maximized without affecting the scanning by the electron beam 15 at all, so that it is possible to obtain a further vibration isolation effect. Become.

The present invention is not limited to the above-described embodiment, but can be applied to a multi-neck type color picture tube having three necks 12 as shown in FIG. In this case, since the vibration isolators 26 are arranged between the electron beams 15, a total of two vibration isolators 26 are arranged. Further, the present invention can be similarly applied to a multi-neck type color picture tube having three or more necks 12.

When the intermediate portion between the vibration isolator 26 and the shadow mask 16 is fixed by welding or the like, the amplitude of the shadow mask 16 caused by vibration can be reduced, and the vibration can be suppressed more effectively. Further, the shape of the opening 25 of the shadow mask 16 can also be adjusted by a round hole or the like, and the mounting position of the elastic support 22 can be set at the corner of the face panel 11. The shape of the elastic support 22 can also be a U-shape, an N-shape, or the like, and the first and second arm members 23, 24
It is needless to say that other various applications and modifications are possible, for example, the cross-sectional shape of is not limited to a triangle, and other shapes can be adopted, and the phosphor screen 14 may have a black matrix configuration. .

[0048]

As described above, according to the present invention, there is provided a color image receiving apparatus employing a multi-neck type large phosphor screen having a plurality of electron guns in which a shadow mask is stretched on a mask frame by a stretch stretching method. Even in the case of a tube, the vibration of the shadow mask due to external vibration can be reliably and effectively prevented with a simple configuration without affecting the scanning of the phosphor screen by each electron gun at all.
It is possible to provide a high-quality color picture tube in which deterioration of luminance performance, color shift, and the like, which are caused by the vibration of the shadow mask, are prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a multi-neck type color picture tube according to the present invention.

FIG. 2 is a perspective view showing a multi-neck type color picture tube.

FIG. 3 is an explanatory view showing a display surface of a multi-neck type color picture tube.

FIG. 4 is a perspective view showing a mask frame having a vibration isolating plate constituting a color picture tube according to the present invention.

FIG. 5 is a cross-sectional view showing a configuration example of the vibration isolator.

FIG. 6 is a sectional view showing a dimensional relationship of the vibration isolating plate.

FIG. 7 is a cross-sectional view showing another configuration example of the vibration isolator.

FIG. 8 is a sectional view showing still another configuration example of the vibration isolator.

FIG. 9 is a sectional view showing another configuration of the color picture tube according to the present invention.

FIG. 10 is a sectional view showing a conventional color picture tube.

FIG. 11 is a perspective view showing a mask frame constituting a conventional color picture tube.

[Explanation of symbols]

 11: face panel 12: neck 13: funnel 14: phosphor screen 15: electron beam 16: shadow mask 17: mask frame 18: electron gun 23: first arm member 24: second arm member 25: aperture 26 : Anti-vibration plate

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tokuo Hashimoto 1-9-2, Hara-cho, Fukaya-shi, Saitama F-term in Toshiba Fukaya Factory Co., Ltd. 5C031 EE15 EG06 EH04 EH08

Claims (4)

[Claims] 1. A rectangular face panel having a phosphor screen on an inner surface thereof; a funnel-shaped funnel connected to the face panel and having a plurality of necks; A shadow mask facing at a predetermined interval, a plurality of electron guns housed in each of the necks for emitting an electron beam for scanning a predetermined portion of the phosphor screen through the shadow mask, and extending the shadow mask. A mask frame that is stretched and held; and a vibration isolator arranged in contact with or close to the shadow mask, wherein the vibration of the shadow mask is suppressed by the vibration isolator. Color picture tube. 2. The color picture tube according to claim 1, wherein said vibration isolator is disposed opposite to both side surfaces of said shadow mask so as to sandwich said shadow mask. 3. The vibration isolator according to claim 1, wherein a width of the vibration isolator disposed on the phosphor screen side is set smaller than that of the vibration isolator disposed on the electron gun side. 2
A color picture tube as described. 4. The width A of the vibration isolator, the length H of the phosphor screen in the horizontal direction, the distance Lo from the center of the phosphor screen to the center of deflection, and the phosphor screen at the center of the phosphor screen. The distance is set as follows: P ≦ A <(H × q) / (2 × Lo), where q is the distance between the shadow mask and the opening pitch of the shadow mask. A color picture tube as described.