JPH0256835A - Shadow mask structure - Google Patents

Abstract

PURPOSE:To make the frame in a thin thickness and of a low thermal capacity and to improve the rigidity by forming polygonal or circular recesses at the interval wider than the thickness of a flange and in an even depth on almost the whole surface of the flange of the frame. CONSTITUTION:Polygonal or circular recessed 6 are provided formed along almost the whole surface of the flange surface 22a of a frame by the press formation process at the interval S wider than the thickness t of the flange surface 22a. And the recesses 6 have the almost even depth from the bottom surface of the flange surface 22a, and ribs 7 are formed between the recessed 6 combining each other on the flange surface 22a. As a result, the thickness in the appearance of the flange surface 22a is increased making the original thickness t plus pushing-up depth d (t+d). Consequently, the rigidity of the whole frame is improved, and the weight and the thermal capacity can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a shadow mask structure installed inside the panel of a color picture tube.

[Prior Art] FIG. 6 is an exploded perspective view showing the general configuration of a color picture tube. In FIG. 0, (1) is a panel, and (la) is a fluorescent screen formed on the inner surface of the panel (1). , (2) is a shadow mask structure which is a color selection electrode.

(24) is the electron beam passage hole, (3) is the panel part (1)
The funnel (0) is an electron gun that emits an electron beam toward the phosphor screen (1a), and the shadow mask structure (2) is attached to the top, bottom, left and right sides of the frame (22) at approximately the center. It is held in the panel (1) opposite the phosphor screen (la) via a welded mask suspension holder (5).

The inner surface of the panel (1) is formed into a spherical shape, and the shadow mask structure (2) has a shape of 9 as shown in FIG.
A shadow mask body (21) having a color selection function and a frame (21) that holds this shadow mask body (21).
2) and a mask suspension holder (5). The shadow mask main body (21) is generally fixed by welding the shadow mask skirt portion (23) to the frame (22).

The shadow mask body (21) is formed into a spherical shape that is almost similar to the inner surface of the panel (1), and the frame (22) has a diameter of 0.8 to maintain the strength of the shadow mask body (21). It is formed into a frame shape having a flange portion (22a) on the bottom surface as shown in FIG. 7 by using a hot-rolled steel plate or a cold-rolled steel plate with a thickness of ~2.5mm.

FIG. 8 is an exploded perspective view of the color picture tube disclosed in Japanese Patent Application Laid-Open No. 61-225738. As shown in FIG. 9, the mask suspension holder (5) is arranged at the corner of the frame (22). The so-called "Shadow Mask Corner Suspension System" has the following features compared to the "Shadow Mask Middle Suspension System" shown in Figures 6 and 7. has.

First, since the mask suspension holder (5) is attached to the corner of the frame (22), which has relatively high rigidity, the frame (22) can be made thinner and lighter compared to the middle suspension system, and as a result, the heat capacity is smaller, so the time required to reach thermal equilibrium when the frame (22) is heated by the electron beam during operation of the color picture tube becomes shorter. Furthermore, in corner suspension systems, the frame (22
) is supported by the mask suspension holder (5), so that the torsional deformation mode of the frame (22) as shown by the broken line in FIG. 10, which occurs in the middle suspension system, is less likely to occur. In the figure, frame (22)
and the suspension point (5a) are modeled and illustrated. Note that the amount of deformation indicated by the broken line in FIG. 1O is usually several turns m to several + IL m per turn.

For example, to increase the rigidity of the frame (22) against torsional deformation modes as shown in FIG.

A recess (23) extruded into a crescent shape in the thickness direction of the frame was provided at the corner portion of the zigzag portion (22a) for reinforcement. Also, in the corner suspension system shown in Fig. 9, crescent-shaped recesses are similarly provided at the corners of the frame (22) in order to increase the rigidity of the frame and maintain flatness. There were many.

[Problems to be Solved by the Invention] The conventional shadow mask structure is configured as described above, and the length ratio of the long side and short side of the frame (22), that is, the aspect ratio L/H is about 4/ It was 3. However, for example, in high-definition television standards, this aspect ratio L/H is set at approximately 111/9. For this reason, the length L of the long side of the frame (22) is longer than before.1 For example, in the frame through-suspension system shown in Fig. 7, the length L from the suspension point (5a) to the corner of the frame (22) is Since the length L/2 becomes longer, the rotational moment M generated by the suspension point and the frame's own weight also becomes larger, and the torsional deformation shown in FIG. 10 becomes more likely to occur. Also in the frame corner suspension system shown in FIG.

Since the length L of the long side of the frame (22) becomes longer, the first
A problem arises in which the intermediate part of the frame (22) is bent and deformed as shown by the broken line in FIG. Here, the amount of deflection deformation shown by the broken line in FIG. 12 is usually from several ILm to several tens of ILm.

Such torsional and flexural deformations are not only static, but also appear in the form of vibrations if the deformation is repeated over time, which is undesirable. Therefore, in order to reduce such deformations (static and dynamic), Therefore, it is necessary to increase the rigidity of the frame (22). -Generally, in order to increase the rigidity against torsional deformation and deflection deformation shown in Figs. 10 and 12, it is necessary to increase the second moment of area, However, the cross-sectional shape of the conventional shadow mask frame (22) is an L-shaped cross-sectional shape with plate thickness t, height A, and radius B as shown in FIG. 13(a). (In this case, the bending moment shown in Figure 13(b))
When M acts, in order to increase the moment of inertia of area, either increase the height A of the frame (22) or
It is well known that increasing the plate thickness t is effective.

However, for example, if A of frame (22) is made higher,
Inevitably, the distance e between the panel (1) and the inner surface becomes narrower, resulting in a problem that the panel (1) and the frame (22) are likely to come into contact with each other during the manufacturing process of the color picture tube. In addition, if the plate thickness t of the frame (22) is increased, the rigidity becomes stronger, but this goes against the demand for a thinner frame (22) with a lower heat capacity, and there are problems such as a longer time required to reach thermal equilibrium. arise.

Furthermore, if the thickness t of the frame (22) is increased, the weight of the frame (22) will also increase.
Even if the rigidity of the mask suspension holder (5) is improved, if the color picture tube is subjected to an impact load such as being dropped, the mask suspension holder (5)
There are problems such as deformation of the color picture tube, which increases the risk of interfering with the operation of the color picture tube.

This invention was made in order to solve the above-mentioned problems, and it is possible to reduce the heat capacity by reducing the thickness of the frame, and also to obtain a shadow mask structure in which the frame has high rigidity and is resistant to mechanical deformation. The purpose is to

[Means for Solving the Problems] A shadow mask structure according to the present invention is formed by forming polygonal or circular recesses over almost the entire surface of the flange surface of the frame at intervals wider than the plate thickness of the flange. Characterized by points.

[Function] The frame according to the present invention is formed so that a polygonal or circular recess extends over almost the entire surface of the flange surface in the thickness direction, so that the rib portion formed between the recesses The apparent thickness of the flange surface increases by the height of . As a result, the rigidity of the frame is improved. Furthermore, since the aforementioned rib portions are connected to each other, they reinforce each other against various load directions, thereby further increasing the rigidity of the frame.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1st
This figure is an exploded perspective view of a color picture tube using a shadow mask structure according to an embodiment of the present invention, and FIG. 2 is a view of the shadow mask structure of this embodiment mounted on a panel as seen from the electron gun side.

In the figure, (8) is the flange surface (22a) of the frame.
Hexagonal recesses (7) are formed between each recess (8) by extrusion processing over almost the entire surface at intervals wider than the plate thickness of the flange surface. The rib portions (7) are connected to each other.

Figure 3 (a) is a sectional view taken along the line a-a in Figure 2, and Figure 3 (
b) is a sectional view taken along the line b-b in Figure 2. In Figure 0, the recesses (8) are extruded to a depth d from the bottom of the flange surface (22a) and at a spacing S between the recesses. , the interval S is larger than the plate thickness t. Since the rib portion (7) is formed between the recesses (6), the flange surface (2)
The apparent thickness of 2a) is the sum (t+d) of the original thickness t of the flange surface (22a) and the extrusion depth d, increasing the rigidity of the frame (2). As a result, the rigidity against twisting and bending deformations as shown in FIGS. 10 and 12 is improved.

FIG. 4 is a partially enlarged perspective view of the flange surface (22a) of this embodiment, showing the recesses (8a), (8b), (8c).
Rib portions (7a), (7b), (
For example, suppose that a bending moment M is added to (7C) in 7c).

The force applied to the rib portion (7C) is the force applied to the rib portion (7a), (7b
) direction. Therefore, since the rib portion (7) is continuously formed over almost the entire surface of the frame flange surface (22a) as shown in FIG. 2, it can withstand loads applied to the frame (22) in various directions. In addition to the above-mentioned increase in apparent thickness, the rigidity of the frame (22) is further improved.

In the above embodiment, the shape of the recess (6) is approximately hexagonal and is formed over almost the entire surface of the flange surface (22a). However, the shape of the recess (8) is, for example, 5 (a) to (c), the recess (6) may be a polygon such as a square or a rectangle, or a circular shape. An example was shown in which extrusion was performed from the electron gun side toward the panel side, but the same effect can be obtained even if the extrusion direction is reversed.

Furthermore, in the above embodiment, the recess (8) is formed on the flange surface (2).
2a) An example was shown in which it was formed over almost the entire surface,
If necessary, any part of the flange surface (22a) may be left as a flat part, and the size (area) of the recess (8) to be formed can be determined as appropriate depending on the plate thickness and extrusion depth. You can choose the size.

[Effects of the Invention] As described above, according to the present invention, polygonal or circular recesses are formed over almost the entire surface of the flange surface of the frame at predetermined, almost uniform intervals at intervals wider than the plate thickness of the flange surface. Since it is formed with depth, the apparent thickness of the flange surface is increased, and the ribs formed between each recess are connected on the flange surface, improving the rigidity of the frame as a whole. Moreover, it is possible to obtain a shadow mask structure that is lightweight and has a small heat capacity.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a color picture tube equipped with a shadow mask structure according to an embodiment of the present invention, and FIG. 2 is a plan view of the shadow mask structure of this embodiment housed in a panel, viewed from the electron gun side. , Figure 3(a). (b) is a sectional view taken along lines aa and b-b in FIG. 2, FIG. 4 is a partially enlarged perspective view of the frame flange portion of this embodiment, and FIGS. ) is a diagram showing the shape of a recess in another embodiment of the present invention, FIG. 6 is an exploded perspective view of a color picture tube of a conventional shadow mask middle suspension system, and FIG. 7 is a shadow mask structure of this conventional example. A partially cutaway perspective view of
Fig. 8 is an exploded perspective view of a color picture tube of a conventional shadow mask corner suspension system, Fig. 9 is a partially cutaway perspective view of the shadow mask structure of this conventional example, and Fig. 1θ is a frame flange corner portion provided with a shadow. FIG. 12 is an explanatory diagram of the bending deformation of the frame of the corner suspension system, and FIG. 13(a) is a perspective view and a sectional view thereof. (b) is an explanatory diagram of the cross-sectional shape of a conventional frame and the bending moment acting on the cross-section of the frame. (2)...Shadow mask structure, (21)...Shadow mask body, (22)...Frame, (22a)
...flange surface, (8) ... recess, (7) ... rib portion. In each figure, the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1 Figure 3 (a) (b) Figure 4 (a) Figure 5 (b) (C) Figure 10 Figure 25: Three-g moon shaped recessed light No. 12 Figure Figure Figure 13 (a) (b)

Claims (1)

[Claims] (1) On the flange surface of the frame to which the skirt portion of the shadow mask main body is welded, polygonal or circular recesses are formed with almost uniform depth over almost the entire surface at intervals wider than the plate thickness of the flange surface. A shadow mask structure is formed.