JPH10283945A - Color picture tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color picture tube which is made lightweight without decreasing the rigidity of its mask frame and has a stable landing characteristic. SOLUTION: A color picture tube has a shadow mask 25, which comprises a mask main body 30 and a mask frame 33 provided with an inside overhanging portion at one end of a side wall portion attached to the periphery of the mask main body 30 and which is supported by a stud pin 24 provided on a panel 22 and by elastic support 35 attached to the side wall portion of the mask frame and locked to the stud pin. In this case, irregular patterns reinforcing the mechanical strength of the mask frame are formed on almost the entire inside and outside surfaces of the side wall portion and inside overhanging portion of the mask frame.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube of a shadow mask type, and more particularly to a color picture tube in which the mechanical strength of a mask frame of the shadow mask is reinforced.

[0002]

2. Description of the Related Art In general, a color picture tube is opposed to a phosphor screen formed of a three-color phosphor layer which emits blue, green and red light formed on the inner surface of a substantially rectangular panel, and has a substantially rectangular inside. A color image is provided by disposing a shadow mask having a shape, deflecting three electron beams emitted from an electron gun by a magnetic field generated by a deflecting device, and selecting the shadow mask to scan the phosphor screen horizontally and vertically. Is formed in a structure for displaying.

In general, as shown in FIG. 4, the shadow mask has a substantially rectangular mask body 2 having a large number of electron beam passage holes 1 formed on a surface facing the phosphor screen.
And a side wall 3 attached to the periphery of the mask body 2
And a substantially rectangular mask frame 5 having an L-shaped cross section provided with an inner protruding portion 4 on one end side of the mask frame 5.

Conventionally, as a method of supporting the shadow mask, as shown in FIG. 5 (a), a substantially rectangular mask frame 5 is formed in a substantially Z-shape at an intermediate portion of each side wall portion 3 of the mask frame 5. The fixing portion 8 at one end of the strip-shaped elastic support 7 is attached by welding, and the locking hole 10 provided at the locking portion 9 at the other end can be attached to and detached from the stud pin provided on the inner wall of the panel. (B), a substantially V-shaped elastic member is provided on the side wall 3 at each corner of the substantially rectangular mask frame 5 as shown in FIG. The fixing portion 8 of the support 7 is attached by welding, and the locking hole 10 provided in the locking portion 9 at the other end opposite to the fixing portion 8 can be detachably attached to a stud pin provided on the inner side wall of the panel. Corner support system that supports the inside of the panel by locking There is.

[0005]

As described above, as a method of supporting the shadow mask of the color picture tube, a strip-shaped elastic plate formed in a substantially Z-shape at the intermediate portion between the side walls of the mask frame. An on-side support method in which a support is attached and supported, and a corner support method in which a substantially V-shaped elastic support is attached to and supported on a side wall of each corner of the mask frame.

However, color picture tubes supporting a shadow mask by these methods have the following problems.

Generally, a shadow mask has a thickness of 0.1 to 0.1 mm.
A plate thickness of 0.8 mm is formed around the periphery of a mask body with a low mechanical strength in which a large number of electron beam passage holes are formed on a plate surface of about 0.3 mm.
A mask frame having an L-shaped cross section of about 2.0 mm is attached, and the mask body is reinforced by the mask frame.

However, when the shadow mask is supported by the above-mentioned on-side support method, when the thickness of the mask frame is reduced in order to reduce the weight of the color picture tube, the solid line in FIG. As shown as
The rigidity of the shadow mask 12 is reduced, and the four corners are twisted. In order to avoid this decrease in rigidity, it is necessary to make the thickness of the mask frame sufficiently large or to increase the side wall portion, and there is a limit to the weight reduction of the shadow mask. Therefore, in the on-side support method, the weight of the mask frame becomes relatively large and the heat capacity becomes large. Therefore, the mask main body is heated by the collision of the electron beam at the beginning of the operation of the color picture tube, and the heat of the mask main body is transmitted to the mask frame, and the time until the mask main body and the mask frame are in a thermal equilibrium state is lengthened. . as a result,
The unstable landing state of the electron beam with respect to the three-color phosphor layer is prolonged, and during that time, the color purity is deteriorated. When an external impact or vibration is applied due to an increase in the weight of the shadow mask, a large load is applied to the elastic support, and the deformation or displacement of the shadow mask occurs, and the landing characteristics of the electron beam with respect to the three-color phosphor layer change. There are problems such as deterioration of image quality.

On the other hand, when the shadow mask is supported by the corner support method, since the shadow mask is supported at the four corners of the mask frame, the twist at the four corners is reduced as compared with the above-described side support method. Therefore, the thickness of the mask frame can be reduced to reduce the weight. As a result, the heat capacity of the mask frame can be reduced, and the landing unstable state at the beginning of the operation of the color picture tube can be shortened.

However, even in this corner support method, when the color picture tube becomes large, for example, when the screen size becomes 30 inches or more, the weight of the mask frame increases, and a large load is applied to the elastic support. If the thickness of the mask frame is reduced in order to reduce the weight, the rigidity against twisting and bending is reduced, and the shadow mask is deformed by repeated attachment and detachment in the color picture tube manufacturing process. Further, even after being incorporated in a color picture tube, the shadow mask is deformed, which leads to deterioration in production yield and screen quality. Furthermore, in a horizontally long color picture tube having a screen aspect ratio (ratio of aspect ratio) of 16: 9, rigidity against twisting and bending is further reduced as compared with a normal color picture tube having a screen aspect ratio of 4: 3. However, there is a problem that the production yield and the screen quality are significantly deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a color picture tube having a stable landing characteristic by reducing the weight without impairing the rigidity of the mask frame.

[0012]

SUMMARY OF THE INVENTION A mask frame having a mask body opposed to a phosphor screen formed on an inner surface of a panel, and an inner protruding portion provided at one end of a side wall attached to a peripheral portion of the mask body. A color picture tube having a shadow mask comprising a stud pin provided on a panel and an elastic support member attached to a side wall portion of the mask frame and engaged with the stud pin. An irregular pattern for reinforcing the mechanical strength of the mask frame was formed on almost the entire inner and outer surfaces of the side wall portion and the inner overhang portion of the frame.

Further, the concavo-convex pattern is constituted by a plurality of polygonal patterns adjacent to each other.

Further, the depth of the concave portion of the concave-convex pattern is set to 0.3 mm to 1.0 mm.

[0015]

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

FIG. 1 shows a color picture tube according to an embodiment of the present invention. This color picture tube has an envelope composed of a substantially rectangular panel 22 provided with a skirt portion 21 around an effective portion 20 and a funnel 23 having a funnel shape. On the inner surface of the effective portion 20 of the panel 22, a phosphor screen 24 made of a three-color phosphor layer that emits blue, green, and red light is provided. A substantially rectangular shadow mask 25 described later is arranged inside the phosphor screen 24 at a predetermined distance from the phosphor screen 24. On the other hand, an electron gun 28 for emitting three electron beams 27B, 27G, and 27R is disposed in a neck 26 of the funnel 23. Then, the three electron beams 27B, 27G, 27R emitted from the electron gun 28
Are deflected by a deflecting device 29 mounted outside the funnel 23, and selected by a shadow mask 25,
The phosphor screen 24 is formed so as to display a color image by scanning the phosphor screen 24 horizontally and vertically.

The shadow mask 25 has a substantially rectangular mask body 30 having a large number of electron beam passage holes formed on an effective surface facing the phosphor screen 24 and a skirt portion provided around the effective surface. , As shown in FIG.
Side wall 31 attached to the skirt of the mask body
And a substantially rectangular mask frame 33 having an L-shaped cross section provided with an inner protruding portion 32 at one end thereof. The shadow mask 25 is formed on the side wall 31 of the mask frame 33.
Is attached outside the skirt portion of the mask body 30. Then, the shadow mask 25 is mounted on the panel 22.
Stud pins 3 provided on the skirt portion 21
4 and a plurality of elastic supports 35 attached to the side wall 31 of the mask frame 33 and engaged with the stud pins 34.

In particular, in this embodiment, concavo-convex patterns adjacent to each other are formed on substantially the entire inner and outer surfaces of the side wall 31 and the inner projection 32 of the mask frame 33. In this embodiment, as shown in FIG. 3, the concavo-convex pattern is a tortoise-shaped pattern in which the concave portion 37 has a turtle-like shape and the space between adjacent concave portions 37 forms a convex portion 38. 0.3 mm to 1.0 mm from part 38
At a depth d. Such a concavo-convex pattern is formed by embossing, and in a shadow mask which is attached with the side wall of the mask frame outside the skirt portion of the mask body as described above, the concave portion 37 projects outside the mask frame 33. It is good to form it.

As described above, when the uneven pattern is formed on almost the entire inner and outer surfaces of the side wall 31 and the inner projection 32 of the mask frame 33, the mask frame 33 can be reinforced and its mechanical strength can be increased. Therefore, the thickness of the mask frame 33 can be reduced without impairing the rigidity of the mask frame 33, and the landing of the electron beams 26B, 26G, 26R on the three-color phosphor layer can be performed without increasing the weight of the shadow mask and the heat capacity of the mask frame. A color picture tube having stable characteristics can be constructed.

In the above-described embodiment, the concave and convex pattern in which the concave portion is formed in the side wall portion and the inner overhang portion of the mask frame is formed, but the concave and convex pattern is formed by a polygon such as a triangle, a quadrangle, a pentagon, and an octagon. The shape may be other shapes such as a circle.

Further, in the above embodiment, the irregularities on the inner and outer surfaces of the side wall portion and the inner projecting portion of the mask frame are different, but the irregularities on the inner and outer surfaces may be the same.

[0022]

According to the present invention, there is provided a shadow comprising a mask body facing the phosphor screen formed on the inner surface of the panel, and a mask frame provided with an inner protrusion at one end of a side wall attached to the periphery of the mask body. Having a mask,
In a color picture tube having the shadow mask supported by a stud pin provided on a panel and an elastic support member attached to a side wall of the mask frame and locked to the stud pin, a color picture tube having a side wall and an inner protrusion of the mask frame is provided. A concave / convex pattern for reinforcing the mechanical strength of the mask frame is formed on almost the entire inner and outer surfaces, and the concave / convex pattern is composed of a plurality of polygonal patterns adjacent to each other. To 0.
If it is 3mm to 1.0mm, the mask frame is reinforced,
The mechanical strength can be increased, the thickness of the mask frame can be reduced without reducing the rigidity of the mask frame, the weight of the shadow mask and the heat capacity of the mask frame can be increased without increasing the electron beam A color picture tube having stable landing characteristics can be constructed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a color picture tube according to an embodiment of the present invention.

FIG. 2 is a view showing a shape of a mask frame of a shadow mask of the color picture tube.

FIG. 3A is a plan view showing the shape of a concavo-convex pattern formed on a side wall portion and an inner protruding portion of the mask frame, and FIG. 3B is a cross-sectional view taken along the line BB.

FIG. 4 is a partially cut-away view showing a configuration of a shadow mask of a conventional color picture tube.

FIGS. 3A and 3B are diagrams showing different shadow mask support methods. FIG.

FIG. 6 is a diagram for explaining a problem of a conventional shadow mask.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 22 ... Panel 24 ... Phosphor screen 25 ... Shadow mask 30 ... Mask main body 31 ... Side wall part 32 ... Inner overhang part 33 ... Mask frame 34 ... Stud pin 35 ... Elastic support body 37 ... Concave part 38 ... Convex part

Claims (3)

[Claims] 1. A shadow comprising a mask main body formed on an inner surface of a panel and facing a phosphor screen, and a mask frame provided with an inner projection on one end side of a side wall attached to a peripheral portion of the mask main body. Having a mask,
In a color picture tube, wherein the shadow mask is supported by a stud pin provided on the panel and a resilient support attached to a side wall of the mask frame and engaged with the stud pin, the mask frame includes the side wall. A color picture tube, wherein a concave / convex pattern for reinforcing the mechanical strength of the mask frame is formed on substantially the entire inner and outer surfaces of the inner overhang portion. 2. The color picture tube according to claim 1, wherein the concave / convex pattern comprises a plurality of polygonal patterns adjacent to each other. 3. The concave / convex pattern has a concave depth of 0.3 mm or more.
3. The color picture tube according to claim 1, wherein said color picture tube is 1.0 mm.