JPH01117245A - Color image receiving tube - Google Patents

Abstract

PURPOSE:To prevent the vibration of a shadow mask and ensure the easy assembly thereof by changing the relative position of a shadow mask skirt part and a mask frame for the support thereof between the long and short sides of the shadow mask. CONSTITUTION:The skirt part 7b of a shadow mask 7 is supported with and fixed to a mask frame 8. The skirt part 7b is so fixed as to be outside the mask frame 8 at the long side and corner of the shadow mask 7. Also, the skirt part 7b is so fixed as to be inside the mask frame 8 at the short side of the shadow mask 7. According to the aforesaid construction, the skirt part 7b at the short side is subjected to stress 17 in an inward direction and the main plane 7a of the shadow mask 7 is subjected to stress in an outward direction. Consequently, the shape maintenance capability of the shadow mask 7 is increased and the shadow mask 7 is always maintained at a constant shape. Also, the joints of the skirt part 7b and the mask frame 8 can be easily worked.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a shadow mask type color picture tube, and particularly to its shadow mask structure.

(Prior Art) Generally, a color picture tube has a substantially rectangular panel ω, a funnel-shaped funnel ■ and a neck ■, as shown in FIG.
A vacuum envelope is constructed from the following.

On the inside of the panel (■) is a phosphor screen consisting of striped phosphor layers that emit red, green, and blue light respectively.
is deposited on the panel, and the so-called in-line electron gun 0, which is arranged in a line along the horizontal axis of the panel and emits three electron beams corresponding to red, green, and blue, is arranged on the neck. ing. In addition, a large number of slit-like openings are vertically arranged in a position close to and opposite to the phosphor screen ( ), and a shadow mask ■ in which a large number of these vertically arranged holes are arranged horizontally is supported and fixed by a mask frame ■. There is. Furthermore, the mask frame 0 has a panel pin (10) embedded in the inner wall of the upright part of the panel ■ by releasing the spring ■.
is secured and supported.

Three in-line electron beams ■ are funnel ■
is deflected by an external deflection device (not shown), scans a rectangular range corresponding to the rectangular panel (■), is color-selected through the aperture of the shadow mask (■), and lands on the striped phosphor layer. It is designed to reproduce images.

In addition, the electron beam is affected by external magnetic fields such as the earth's magnetism, so it may not land accurately on the striped phosphor layer.In order to prevent the color purity of the reproduced image from deteriorating, a ferromagnetic metal plate is placed inside the funnel. A magnetic shield consisting of (1
1) is locked through the frame (c).

As shown in FIG. 3, a shadow mask for a color picture tube is generally made of a flat plate material made of cold-rolled steel plate and formed into a curved shape by press molding. That is, the shadow mask (2) has a curved main surface (7a) having a large number of small holes, and a skirt portion (7b) that is bent and extends from the periphery of this main surface (7a).

A shadow mask having the above shape has conventionally been molded using a molding apparatus as shown in FIG. First, the apparatus shown in FIG.
3) and the punch (14) provided above this knockout (13) to press the main surface (7a) shown in FIG.
) and the bending of the skirt portion (7b) are performed simultaneously. However, when molded in this way, a stress (indicated by arrow 15) is generally exerted that causes the skirt portion (7b) to return to its original shape.

The skirt portion (7b) warps (springback) as shown in FIG. 3, and local deformation (indicated by dotted line 16) occurs in the peripheral area of the shadow mask. Such local deformation (16) is particularly noticeable in the case of high-yield materials such as invar material (36% Ni-Fe alloy).

However, when a color picture tube with the above-described shadow mask structure mounted inside the envelope is installed in a television set and operated, and the sound coming from the speakers installed in the television set is loud, the sound is Panel→
The vibration is transmitted in the order of the spring pin (10) → frame holder 0 → mask frame ■ → skirt portion (7b) → shadow mask body ■, causing the shadow mask body ■ to vibrate. This vibration causes a color shift phenomenon in which the electron beam does not strike the proper phosphor layer, resulting in a problem of degrading the quality of the image drawn on the phosphor screen. In particular, local deformation occurring in the periphery of the short side of the main surface of the shadow mask vibrates abnormally. Further, the larger the size of the shadow mask, that is, the larger the color picture tube, the more remarkable the phenomenon becomes.

(Problems to be Solved by the Invention) In order to address these inconveniences, the present applicant has previously filed a Utility Application filed in 1983-
No. 188155 and Japanese Patent Application No. 59-273635 proposed that the outer diameter of the shadow mask be made larger than the inner diameter of the mask frame to suppress local deformation of the periphery of the shadow mask and vibration of the shadow mask caused by this. . However, as in these conventional examples, when the outer diameter of the shadow mask is larger than the inner diameter of the mask frame, it takes a lot of effort to assemble the entire circumference of the shadow mask to the inside of the mask frame, and sometimes the shadow Since the mask may be deformed, it is not suitable for industrial mass production, and it is necessary to further improve this point.

As mentioned above, the purpose of the present invention is to suppress the vibration of the shadow mask main body due to sounds from speakers, etc., and at the same time, reduce the time required to combine the mask frame and the shadow mask, and reduce the deformation of the shadow mask. An object of the present invention is to provide a color picture tube that is highly mass-producible.

[Structure of the invention]

(Means for Solving the Problems) The present invention arranges the skirt portion of the shadow mask inside the mask frame on the short side of the shadow mask structure, and outside the mask frame on the long side. It is a color picture tube.

(Function) According to the color picture tube having the shadow mask structure as described above, it is possible to suppress the warping of the short side skirt portion due to press molding of the shadow mask, and the short side is particularly vulnerable to vibration. The tension strength of the side peripheral area is maintained, and vibration of the shadow mask is suppressed. In addition, on the long side of the shadow mask structure, the skirt portion of the shadow mask is placed outside the mask frame, making it easy to combine the shadow mask and the mask frame, and also allowing for deformation of the shadow mask at that time. is also reduced.

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

The color picture tube according to this embodiment is almost the same as that shown in FIG. 2 except for the shadow mask structure, and the same parts will not be particularly described. That is, FIGS. 1(a) to (g)
1 shows a shadow mask, a frame, and a shadow mask structure (support holder is omitted) in which they are combined for explaining the present invention in detail. First, the first
As shown in Figures (d) and (e), the main surface (7a) having a large number of through holes is formed into a curved surface by a commonly known etching method, and the peripheral part is formed into a skirt part (7a) bent to support the main surface. 7b) to make a rectangular shadow mask. -Then, the outer diameter dimension between the opposing skirt portions in the long axis direction of the rectangular shadow mask is, for example, O.
m, and the dimension of the shadow mask main surface (7a) along the long axis is, for example, O. A shadow mask is completed. Such a shadow mask ■ is combined with the mask frame (f) shown in FIG. Two notches (8-3) are provided in each case. The intermediate area between these two notches (8-3) (
8-4) is formed to protrude slightly outward. And the dimension of the main surface (7a) of the shadow mask is 0.4
and the opposing intermediate regions in the long axis direction of the mask frame (
The distance between the inner sides of the upright edges of 8-4), that is, the relationship with the inner diameter dimension IF of the frame is set so that ON≧IF. Figures 1 (a) to (c) show the combination of the shadow mask (2) and the mask frame (c) as described above.
).

In the figure, the skirt portion (7b) of the shadow mask is arranged inside the mask frame on the short side of the shadow mask structure, and is arranged on the outside of the mask frame on the long side of the shadow mask structure. ing.

As shown in FIG. 1(b), the shadow mask (2) assembled in this way has the skirt portion (7b) on the short side of the shadow mask (2) receiving an inward stress (17), and the main surface (7a) ) is always subjected to outward stress (18), so that the shadow mask (2) has an increased ability to maintain its shape and can always maintain a constant shape. A color picture tube equipped with such a shadow mask structure has internal stress (17) (I
s) works and the shadow mask (2) has a high ability to maintain its shape, so that the peripheral region on the short side, which is particularly vulnerable to vibration, is hard to vibrate, and an image with less color shift phenomenon can be obtained. In addition, in the present invention, the skirt portion of the shadow mask is disposed inside the mask frame only in a partial area rather than the entire circumference of the shadow mask structure. Since only the short sides are placed on the mask frame, and the long sides and corners are placed outside the mask frame, it is easy to combine the shadow mask and mask frame, reducing the time required. We were able to significantly reduce mask deformation during alignment.

〔Effect of the invention〕

As described above, according to one aspect of the present invention, it is possible to provide a high-quality color picture tube that has a shadow mask structure in which stress is always applied to the shadow mask main body through the skirt portion, which is easy to manufacture, and is highly industrially mass-producible. be able to.

[Brief explanation of the drawing]

FIGS. 1(a) to (g) are diagrams for explaining one embodiment of the present invention, FIG. 2 is a sectional view for explaining a general color picture tube, and FIG.
The figure shows an enlarged cross-section of the main part of an example of a conventional shadow mask°
FIG. 4 is a diagram illustrating a shadow mask forming apparatus. ■・・・Panel ■・・・Funnel■・・
・Neck)... Fluorescent screen ■... Electron beam ■... Electron gun ■... Shadow mask
(7a)...Main surface (7b)...Skirt part
(to)...Mask frame (16)...Local deformation
(17), (1g)...Internal stress agent
Patent Attorney Noriyuki Ken Yudo Kikuo Takehana Figure 1 x-x' Figure 1 x-x' Figure 1 Figure 2 2f/3 Figure 4

Claims (1)

[Scope of Claims] 1) A rectangular main surface portion that is close to the screen and has a large number of through holes in its effective surface, and is bent from this main surface portion in a direction opposite to the screen substantially parallel to the tube axis. In a color picture tube, the color picture tube is equipped with a shadow mask structure comprising at least a shadow mask having a skirt portion and a rectangular frame formed by supporting the skirt portion at a plurality of welding points. A color picture tube characterized in that the arrangement of the shadow mask structure is different between the long side and the short side of the shadow mask structure. 2) The skirt portion is located outside the frame on the long side of the shadow mask structure, and the skirt portion is located inside the frame on the short side of the shadow mask structure. The color picture tube according to item 1. 3) The color picture tube according to claims 1 and 2, wherein the skirt portion is located outside the frame at a corner portion of the shadow mask structure.