JPS63195934A - Color cathode-ray tube - Google Patents

Abstract

PURPOSE:To increase a margin of screen effectiveness at diagonal parts by providing the diagonal parts of a supporting frame with the following parts: flat parts where elastic holders are fixed nearly in parallel with a tube axis, and salient parts which are jointed with a shadow mask and projected in the direction of the panel's diagonal parts. CONSTITUTION:Four diagonal parts are provided with flat parts 18, and salient parts 10 which are projected in the direction of panel's diagonal parts, that is, outwardly. Inner walls of these salient parts 19 are welded with an outer wall of a skirt part 10 which is formed by folding a peripheral part of a shadow mask 2. The shadow mask 2 is fixed on a supporting frame 13. Elastic holders 14 fixed on the flat parts 18 of the supporting frame 13 are provided with respective holes 15 on the opposite side of the supporting frame 13 and made to engage with respective stud pins 17, so that the shadow mask and the supporting frames are suspended at a prescribed position. Hence, a margin of an effective diameter on each diagonal part can be increased.

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 a shadow mask holding structure.

(Prior art) In general, a shadow mask type color picture tube has a large number of fine slit holes (■) as shown in Fig. 4, and is made by welding and fixing a shadow mask (■) made of a thin metal plate and a support frame (■). , an elastic holder (
A shadow mask assembly (11) fixed by welding is housed in a glass envelope (not shown). This shadow mask assembly (11) is assembled by fitting a hole drilled at the tip of the elastic holder (6) into a stud pin (not shown) fixed to the inner surface of the panel glass of the envelope. It is suspended and held in place. In such a shadow mask assembly (11), the outer walls of the diagonal corners of the support frame (2) usually have curved surfaces for ease of processing.

Recently, elastic holders have been fixed not at the center of each side of the support frame, but at the diagonal corners, and stud pins on the inner surface of the panel glass are also provided at the diagonal corners to fit them together.

A method of retaining a shadow mask is being considered.

When fixing an elastic holder to a diagonal part of a support frame, if the outer wall of the diagonal part of the frame is curved, it is necessary to fix the elastic holder tightly to the frame and fix it firmly. The shape of the elastic holder is not only difficult to process, but also has too much elasticity due to its curved shape, making it difficult to use for color picture tubes. In order to avoid the problem of smearing that makes it difficult to apply shadow masks several times during manufacturing, for example, a patent application filed in 1986 by the same applicant as the present application was proposed.
No. 63834 proposes a technique in which flat portions are provided at diagonal portions of a support frame.

In addition, there is a trend in recent shadow mask type color receivers toward higher definition, which allows images to be projected in greater detail. In order to achieve high definition, it is necessary to reduce the horizontal pitch of the shadow mask, but this reduces the distance between the phosphor screen and the shadow mask (q value) and also reduces the effective diameter of the screen.

The screen effective diameter must satisfy the standard value, so
It is necessary to enlarge the effective classification area with a large number of fine slits.

However, in general, the mask skirt portion of the shadow mask and the effective classification area are very close to each other, especially in the diagonal portions.

Therefore, if the effective classification range is expanded beyond a certain limit.

During a press operation to form a curved surface of a shadow mask in the manufacture of color picture tubes, the elongation of the slit holes becomes abnormally large, and the shadow mask tends to break. This can be avoided by increasing the outer diameter of the shadow mask, but increasing the outer diameter of the shadow mask (in order to do so, the outer diameter of the frame must also be made larger, and increasing the outer diameter of the frame will prevent the stand pin from interfering with the frame. The 1111 interval becomes narrower, which makes it extremely difficult to attach and detach the tubes, which are carried out several times in the manufacture of color picture tubes.

(Problems to be Solved by the Invention) As described above, the shape of the conventional support frame limits the expansion of the effective area of the shadow mask.
The shape of the elastic holder also becomes complicated, making it difficult to attach and detach.

The present invention solves the above-mentioned drawbacks, increases the margin of the effective diameter of the screen at the diagonal, and has a shadow mask holding structure with a simple shape of the elastic holding body and easy attachment and detachment of the shadow mask. The purpose is to provide a picture tube.

[Structure of the invention]

(Means for Solving the Problems) The color picture tube according to the present invention has been made to solve the above problems, and includes a frame that fixedly supports a rectangular shadow mask. , has a flat part approximately parallel to the tube axis at the diagonal part of the pipe,
and a protrusion protruding in the diagonal direction of the panel is provided at the joint portion of the diagonal portion of the support frame with the shadow mask, one of the elastic holders is fixed to the flat portion, and a protrusion is provided on the other side of the elastic holder. The shadow mask is suspended and held within the panel by fitting the stud pins fixed to the diagonal inner wall surface of the panel into the holes provided.

(Function) According to the present invention, it is possible to increase the margin of the effective diameter of the screen at the diagonal portion of the shadow mask, and moreover, the elastic holder can be made to have a simple structure, and the positional shift of the shadow mask due to the work of attaching and detaching can be prevented. becomes difficult to trigger.

(Example) An example of the present invention will be described with reference to FIG. Figure 1 shows
FIG. 2 is a partial perspective view of the shadow mask assembly, and FIG. 2 is a front view of the shadow mask assembly taken from above;
No. 3 I$1 is a partially enlarged cross section of a color picture tube with a suspended shadow mask assembly.

As shown in Figure 1, the shadow mask ■ is 0.1 to 0.
．． It is a thin rectangular iron plate with a thickness of about 3 mm, and has a large number of fine slit holes ω. The support frame (13) is made of iron and has a rectangular frame shape with a thickness of about 0.5 to 2.0 m. As is clear from Figure 2, the four diagonal parts have a flat part (18) and a protrusion (19) that protrudes outward in the diagonal direction of the panel (see Figure 3). are doing. By welding the outer wall of the bent skirt portion (10) at the peripheral end of the shadow mask (2) to the inner wall of this projection (19), as shown in FIG. 2, the shadow mask is attached to the support frame (13). ■ is fixed.

The diagonal flats (18) are preferably substantially perpendicular to the diagonal axis so that no moments are created that would rotate the support frame (13). In addition, the protrusion (19)
It is also desirable that the mask skirt portion (10) be approximately vertical so that it can be easily welded to the mask skirt portion (10). Support frame (1
As shown in FIG. 3, an elastic holder (14) is fixed to the flat part (18) of the holder (3) by welding. The bottom surface of the protrusion (19) may be a space in order to provide a margin for attaching the elastic holder (14).The elastic holder (14) is made of a material with strong spring properties, such as 5US631, for example. The appropriate thickness is about 0.2 to 0.8 m+m.

As shown in FIGS. 1 and 3, the elastic holder (14) has a hole (15) in a portion opposite to the support frame (13).
is opened, and this is fitted into a stud pin (17) fixed to the inner surface of the glass panel (Q), and the shadow mask and support frame are suspended in a predetermined position.By having such a structure, The margin for the effective diameter of the diagonal portion can be increased, and the shape of the elastic holder is simple, making it easy to attach and detach the shadow mask.

Amber alloy can be used.

〔Effect of the invention〕

In the color picture tube in which the shadow mask is held at the diagonal portion of the present invention, the elastic holder can increase the margin of the diagonal screen effective diameter.1 The elastic holder has a simple structure and can firmly attach the shadow mask. The position of the shadow mask is less likely to shift during attachment and detachment work during the manufacturing process, and the strong fixation provides a structure that is resistant to external impacts.

[Brief explanation of the drawing]

1 to 3 show embodiments of the present invention,
FIG. 1 is a partially enlarged perspective view of a shadow mask, FIG. 2 is a top view, FIG. 3 is a sectional view of a diagonal portion, and FIG. 4 is a top view of a conventional shadow mask assembly. O)...Slit hole, ■...Shadow mask, (13)...Support frame, (to), (1
4)...Elastic holding body. (e...Glass panel, ■, (17)...Stand pin, (15)...Hole, (18)...Flat part, (19)...Protrusion, (10)...・Skirt part. Agent: Patent attorney: Nori Chika, Yudo, Norio Ogo, Figure 1, Figure 2

Claims (3)

[Claims] (1) A shadow mask and a rectangular support frame that firmly supports the shadow mask at multiple locations are provided on the inner surface of the approximately rectangular panel, and the support frame is connected to the diagonal portions of the frame via an elastic holder. In a color picture tube suspended in a color picture tube, a flat part, which is substantially parallel to the tube axis and to which the elastic holder is fixed, is joined to the shadow mask at a diagonal part of the support frame and protrudes in the direction of the diagonal part of the panel. A color picture tube characterized in that it has a protrusion. (2) The color picture tube according to claim 1, wherein the surface of the flat portion of the support frame on which the elastic holder is fixed is substantially perpendicular to the diagonal axis. (3) The color picture tube according to claim 1, wherein the bottom surface of the projection of the support frame is a space.