JPH08315744A - Color picture tube - Google Patents

Abstract

PURPOSE: To provide a color picture tube to maintain excellent beam landing by reducing permanent deformation of elastic support bodies to support a shadow mask. CONSTITUTION: A color picture tube supported so as to be mountable and demountable by plural stud pins by which a shadow mask is arranged on a panel, a fixing part 32 fixed to a mask frame 27 and plural elastic support bodies 34 which are connected to this fixing part by welding or bending and are composed of locking parts 33 with the stud pins, is provided. Opening holes 40 are formed in installing parts of the elastic support bodies of the mask frame, and support part opening preventive parts 38 having claws to be locked inside the mask frame by passing through the opening holes of its mask frame are arranged in the locking parts of the elastic support bodies.

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, and more particularly to a color picture tube in which deviation of beam landing due to deformation of mask supporting means for supporting a shadow mask is prevented.

[0002]

2. Description of the Related Art Generally, a color picture tube has an envelope composed of a substantially rectangular panel and a funnel joined to the panel, and a three-color phosphor layer formed on the inner surface of the panel. A substantially rectangular shadow mask is arranged inside the phosphor screen at a predetermined distance. A three-electron beam emitted from the electron gun is deflected by a deflecting device, and the phosphor screen is horizontally and vertically scanned through the shadow mask to display a color image. The shadow mask is usually a substantially rectangular mask body having a large number of electron beam passage holes formed on the surface facing the phosphor screen, and a substantially rectangular mask body attached to the peripheral portion of the mask body. And a mask frame.

As a method of supporting the shadow mask, as shown in FIG. 6, elastic supports 2 are attached to the four corners of the shadow mask 1, and the radiation direction of the shadow mask 1 generated when the shadow mask 1 is heated by the collision of the electron beam 3 is applied. The elastic support 2 is deformed by the thermal expansion as shown by the broken line 4, and the shadow mask 1 is pushed up toward the phosphor screen 6 as shown by the broken line 5, whereby the electron beam generated by the thermal expansion in the radial direction is generated. The phosphor layer 8 is corrected by correcting the displacement of the passage hole 7.
The method of suppressing the deviation of the beam landing with respect to
It is disclosed in Japanese Patent Publication No. 46-4104.

The following structures (a) to (c) are known as specific examples of the elastic support 2 based on the beam landing deviation correction principle.

(A) As shown in FIG. 7, the elastic support 2
Is bent into a substantially Z-shape, one end of which serves as a fixing portion 10 for the mask frame 9, and the other end of which serves as a locking portion 13 with a stud pin 12 provided on the panel 11. However, with respect to this structure, the bending portion 14 is not plastically deformed as shown by the broken line to return to the original state by the attachment and detachment of the shadow mask 1 which is repeated in the manufacturing process of the color picture tube (mainly the phosphor screen forming process). There is a problem that the permanent deformation occurs and the position of the shadow mask 1 changes with respect to the phosphor screen 6.

(B) As shown in FIG. 8A, the elastic support 2 is bent into a substantially U shape, one end of which is fixed to the mask frame 9 and the other end of which is provided on the panel 11. The stud pin 12 is engaged with the stud pin 12. With this structure, even if the shadow mask 1 is repeatedly attached and detached, the welding point 1 between the mask frame 9 and the fixed portion 10
Since it bends in a wide range on the side of the bent portion 14 starting from 6,
Permanent deformation that does not return to the original state is avoided. However, due to an external impact applied when the color picture tube is transported, a force F perpendicular to the plate surface is generated around the locking hole 17 with the stud pin provided in the locking portion 13, as shown in (b).
When 1 acts, a couple F2 in the direction opposite to F1 acts on the fixed portion 10, causing permanent deformation, and the phosphor screen 6
On the other hand, the position of the shadow mask 1 is likely to change. The permanent deformation of the elastic support 2 is caused by the fixing portion 10 shown in FIG.
The bending angle θ of the bent portion 14 between the locking portion 13 and the locking portion 13 becomes small, especially at both sides 18a and 18b of the bent portion 14,
This is because the curvature of the bent portion 14 becomes small, and it appears as the deformation indicated by the broken line in (d).

(C) As shown in FIG. 9A, a fixing portion 10 for fixing the elastic support 2 to the mask frame 9 and a locking portion 13 for locking the stud pin 12 provided on the panel 11 are provided. It is composed of two members, and these fixing portion 10 and locking portion 1
Each one end of 3 is welded and formed in a substantially U shape. With this structure, the strength of the weld end is
It can be made higher than the elastic support shown in (a).
Moreover, as shown in (c), when the shadow mask is repeatedly attached and detached to bend the locking portion 13, the mask frame 9
Starting from a welding point 16 between the fixing portion 10 and the fixing portion 10,
Since the bending occurs in a relatively wide range near the welded portion between the locking portion 13 and the locking portion 13, concentration of stress can be avoided, and permanent deformation that does not return to the original state can be reduced. However, when a force F1 perpendicular to the plate surface acts around the locking hole 17 with the stud pin provided in the locking portion 13 due to an external impact, as shown in FIG. The couple F2 in the direction opposite to the above acts, and the permanent deformation shown by the broken line in FIG. 4D still occurs, and the position of the shadow mask 1 with respect to the phosphor screen 6 easily changes.

In order to reduce the permanent deformation of the elastic support 2 shown in (b) and (c) to the extent that there is no practical problem, the plate thickness of the fixing part 10 and the locking part 13 should be increased. However, if the plate thicknesses of the fixing portion 10 and the locking portion 13 are increased, the spring pressure increases, which makes it difficult to attach and detach the shadow mask 1, and also the shadow mask 1
Transform. Therefore, there is a problem that these elastic supports 2 must be compromised in consideration of impact resistance and detachability.

[0009]

As described above, as a structure of the elastic support member for supporting the shadow mask, the fixing portion fixed to the mask frame of the shadow mask and the stud pin provided on the panel are engaged. There is one in which a stopper is connected by welding or bending to form a substantially U-shape. However, these conventional elastic supports are permanently deformed by an external impact, and the position of the shadow mask is displaced with respect to the phosphor screen. In order to reduce the permanent deformation of these elastic supports to the extent that there is no practical problem, the plate thickness of the fixing part and the locking part may be increased. However, if the plate thickness is increased, the spring pressure increases and the shadow mask Not only is it difficult to put on and take off, but it also deforms the shadow mask. Therefore, there is a problem that these elastic supports must be compromised in consideration of impact resistance and detachability.

The present invention has been made in view of the above problems, and forms a color picture tube which maintains a good beam landing by reducing the permanent deformation of the elastic support member supporting the shadow mask due to an external impact. The purpose is to do.

[0011]

A substantially rectangular mask frame is provided in a peripheral portion of a substantially rectangular mask body so as to face a phosphor screen formed on an inner surface of the substantially rectangular panel. The attached shadow mask is placed,
A plurality of elastic supporting members each including a plurality of stud pins provided with the shadow mask on the panel, a fixing portion fixed to the mask frame, and an engaging portion of the stud pins connected to the fixing portion by welding or bending. In the color picture tube which is detachably supported by, an opening is formed in the mounting portion of the elastic support body of the mask frame, and the engaging portion of the elastic support body passes through the opening of the mask frame and The locking part release preventing part having a claw for locking inside is provided.

[0012]

As described above, the opening is formed in the mounting portion of the elastic support of the mask frame, and the inner side of the mask frame is formed in the engaging portion of the elastic support through the opening of the elastic support of the mask frame. When the locking portion release prevention portion having the locking claw is provided, even if an external impact is applied to the elastic support body due to the locking of the locking portion release prevention portion claw with respect to the mask frame, the locking portion of the elastic support body It is possible to suppress the change of the locking state with respect to the stud pin and prevent permanent deformation of the elastic support.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings.

FIG. 3 shows a color picture tube which is one of the embodiments. This color picture tube has a substantially rectangular panel 22 in which a skirt portion 21 is provided around the effective portion 20.
And a funnel-shaped funnel 23 joined to the skirt portion 21 of the panel 22, and a three-color phosphor that emits blue, green, and red on the inner surface of the effective portion 20 of the panel 22. A phosphor screen 24 composed of layers is provided, and a substantially rectangular shadow mask 25 is arranged inside the phosphor screen 24 at a predetermined distance from the phosphor screen 24. This shadow mask 25 has a large number of electron beam passage holes formed in the main surface portion facing the phosphor screen 24, and a skirt portion is provided in the peripheral portion of the main surface portion. A substantially rectangular mask body 26 made of a low thermal expansion material such as, and a plate thickness 0.4 to 0.4 mm attached to the skirt portion of the mask body 26.
It is composed of a substantially rectangular mask frame 27 having an L-shaped cross section made of a steel plate of about 1.2 mm, and is detachably supported inside the panel 22 by a mask supporting means described later. On the other hand, an electron gun 29 that emits three electron beams is arranged in the neck 28 of the funnel 23. Then, the three electron beams emitted from the electron gun 29 are deflected by a deflecting device (not shown) mounted outside the funnel 23, and the phosphor screen 24 is horizontally and vertically scanned through the shadow mask 25. As a result, a structure for displaying a color image is formed.

The mask supporting means comprises four stud pins 3 provided at four corners of the skirt portion 21 of the panel 22.
1 and the mask frame 27 as shown in FIGS.
One end of two members consisting of a fixing portion 32 attached to the side walls of the four corners of the above and a retaining portion 33 for retaining the stud pin 31 is welded at one end and formed into a substantially U shape with a plate thickness of about 0.4 mm. It consists of four elastic supports 34 made of stainless steel (SUS631).

Reinforcing portions 36 bent in a key shape are provided on both side edges of the fixing portion 32. On the other hand, the locking portion 33 is composed of a locking portion in which a locking hole 37 for locking the stud pin 31 is formed and an inclined portion, and both side edges of the locking portion are bent toward the fixing portion 32. A pair of locking portion release preventing portions 38 extending in the direction are provided.

A pair of slit-shaped openings 40 through which the pair of locking portion release preventing portions 38 of each elastic support 34 penetrate are formed on the side walls of the four corners of the mask frame 27 with respect to the elastic support 34. ing. Then, the tip end portions of the pair of locking portion release preventing portions 38 of each elastic support body 34 have the pair of openings 4
0 extends through the interior of the mask frame 27, preferably in a non-contact manner. Particularly, in the elastic support 34 of this example, the claw 41 is provided at the tip end portion extending inside the mask frame 27. The claws 41 are provided so as to be separated from the inner surface of the side wall of the mask frame 27 by about 0.1 to 0.5 mm when each elastic support 34 attached to the mask frame 27 is locked to each stud pin 31. Has been.

The major axis of the slit-shaped opening 40 of the mask frame 27 is determined by the claw 41 when the elastic support 34 is assembled.
It is formed in such a size that the locking portion release preventing portion 38 formed with can be inserted.

When the elastic support member 34 for supporting the shadow mask 25 is formed by welding one ends of the fixing portion 32 and the locking portion 33 to each other as described above, the shadow mask 25 is attached and detached in the manufacturing process of the color picture tube. , Elastic support 3
Even if 4 is flexed and locking / unlocking with respect to the stud pin 31 is repeated, the elastic support 34 starts from the welding point of the mask frame and the fixed portion as shown in FIG. 9C.
The shadow mask 2 bends in a relatively wide range near the weld between the fixed portion and the locking portion, and stress is not concentrated at a specific position.
It is possible to avoid the permanent deformation of the elastic support body 34 due to the repeated attachment and detachment of 5.

Further, the locking portion 33 is provided with a locking portion release preventing portion 38 extending in the direction of the fixing portion 32, and a claw 41 is provided at a tip end portion of the locking portion releasing prevention portion 38 so that the mask frame 27 of the mask frame 27 is secured. Since it is located close to the inner surface of the side wall, a force F1 in the direction perpendicular to the plate surface around the locking hole of the locking portion is applied to the fixing portion due to an external impact, as shown in FIG. 9 (c). Even if the force F2 in the opposite direction acts and the locking portion is pulled in the direction away from the fixed portion, the claw 41 at the tip of the locking portion release preventing portion 38 abuts against the inner surface of the side wall of the mask frame 27 to the stud pin 31. The change in the locking position of the locking portion 33 is suppressed,
Permanent deformation of the elastic support 34 due to external impact is also prevented.

Therefore, when the elastic support 34 is constructed as described above, the shadow mask 25 can be stably supported in a fixed position, and a color picture tube that maintains a good beam landing with respect to the three-color phosphor layer is constructed. can do.

Table 1 shows a plate thickness of 0.4 mm for a 25-inch 100-degree deflection in-line type color picture tube that emits three electron beams arranged in a row passing through the same horizontal plane, particularly regarding permanent deformation of the elastic support due to external impact. SUS631 forms the elastic support of this example, the elastic support formed by bending shown in FIG. 8 and the elastic support formed by welding the two members shown in FIG. (Fig. 3
The beam landing deviation after impact is applied in the horizontal direction orthogonal to the Z-axis shown in FIG.

[0023]

[Table 1]

As can be seen from Table 1, a color picture tube A having a shadow mask supported by the elastic support of this example.
Compared with a conventional color picture tube B in which a shadow mask is supported by an elastic support formed by bending, and a conventional color picture tube C in which a shadow mask is supported by an elastic support formed by welding two members. It was possible to reduce the deviation of the beam landing significantly.

Next, an elastic support having a structure different from that of the elastic support will be described.

In the elastic support shown in FIG. 4, the width w2 of the locking portion of the locking portion 33 is narrower than the width w1 of the fixed portion 32 such that w1> w2, and both sides of the mask frame 27 and the fixed portion 32 are provided. A pair of openings 40 and 43 are formed in the
The locking portion release preventing portion 38 that bends both side edges of the locking portion and extends in the direction of the fixing portion 32 passes through the openings 40 and 43, and the tip portion is located inside the mask frame 27. It is configured as follows.

Further, the elastic support shown in FIG.
The width w2 of the locking portion of the locking portion 33 is narrower than the width w1 of the locking portion 33 such that w1> w2, and the free end portion of the locking portion 33 is bent to extend toward the fixing portion 32. The prevention portion 38 is provided, and the openings 40 and 43 are formed in the mask frame 27 and the fixing portion 32 respectively corresponding to the engagement portion release prevention portion 38. The tip portion is located inside the mask frame 27 through 40 and 43.

Even if the elastic support is constructed as shown in FIGS. 4 and 5, the same effect as the elastic support of the above-mentioned embodiment can be obtained.

In the above embodiment, the case where the elastic masks are attached to the four corners of the mask frame to support the shadow mask has been described. However, the present invention has substantially rectangular sides of the mask frame. It is also applicable to a case where an elastic support is attached to the intermediate portion of the shadow mask together with a correction member for correcting thermal expansion of the shadow mask to support the shadow mask.

[0030]

A shadow in which a substantially rectangular mask frame is attached to a peripheral portion of a substantially rectangular mask body so as to face a phosphor screen formed on an inner surface of a substantially rectangular panel. A plurality of stud pins on which a mask is arranged and the shadow mask is provided on a panel, a fixing portion fixed to the mask frame, and a locking portion of a stud pin connected to the fixing portion by welding or bending. In a color picture tube which is detachably supported by individual elastic supports, an opening is formed in the mounting portion of the elastic support of the mask frame, and the opening of the mask frame is formed in the locking part of the elastic support. By providing a locking part release prevention part with a claw that locks through the inside of the mask frame through, the locking of the claw of the locking part release prevention part with respect to the mask frame causes elasticity. Even if the external impact is applied to the lifting member, it can be suppressed a change in the locked state of the elastic support for the stud pins. As a result, it is possible to prevent the elastic support from being permanently deformed, and to configure a color picture tube that maintains good beam landing for the three-color phosphor layer.

[Brief description of drawings]

FIG. 1 (a) is a perspective view showing the structure of an elastic support member that supports a shadow mask of a color picture tube according to an embodiment of the present invention, FIG. 1 (b) is a front view thereof, and FIG. 1C is a side view, and FIG. 1D is a view seen from below.

FIG. 2 is a perspective view showing a mounting structure of an elastic support member to a shadow mask of the color picture tube.

FIG. 3 is a diagram showing the structure of a color picture tube which is an embodiment of the present invention.

4A to 4D are views showing a structure of an elastic support having a structure different from that of the elastic support and a mounting structure for a shadow mask, respectively.

5A to 5D are views showing a structure of an elastic support having a structure different from that of the elastic support and a mounting structure for a shadow mask, respectively.

FIG. 6 is a diagram for explaining a principle of correcting a beam landing deviation due to thermal expansion of a shadow mask.

FIG. 7 is a diagram showing a specific structure of an elastic support that satisfies the above-mentioned beam landing deviation correction principle.

8A to 8D are explanatory views of a specific structure of different elastic supports satisfying the above-described beam landing deviation correction principle.

9A to 9D are explanatory views of specific structures of further different elastic supports that satisfy the above-described beam landing deviation correction principle.

[Explanation of symbols]

 22 ... Panel 24 ... Phosphor screen 25 ... Shadow mask 26 ... Mask body 27 ... Mask frame 31 ... Stud pin 32 ... Fixing part 33 ... Locking part 34 ... Elastic support 37 ... Locking hole 38 ... Locking part opening prevention Part 40 ... Opening hole 41 ... Claw 43 ... Opening hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeo Fukuda 7-1 Nisshin-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Toshiba Electronics Engineering Co., Ltd.

Claims (1)

[Claims] 1. A shadow in which a substantially rectangular mask frame is attached to a peripheral portion of a substantially rectangular mask body so as to face a phosphor screen formed on an inner surface of a substantially rectangular panel. A mask is arranged, and a plurality of stud pins provided with the shadow mask on the panel, a fixing portion fixed to the mask frame, and an engaging portion with the stud pin connected to the fixing portion by welding or bending. In a color picture tube which is detachably supported by a plurality of elastic supports made of, an opening is formed in an attaching portion of the elastic support of the mask frame, and the mask is provided at an engaging portion of the elastic support. A color picture tube, characterized in that a support part opening prevention part having a claw that engages with the inside of the mask frame through an opening of the frame is provided.