JPH01286234A - Shadow mask body structure for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent the deformation of a shadow mask and maintain the color purity and white uniformity of an image screen by fixing the shadow mask and a frame via a component made of a springy material. CONSTITUTION:A material parallelly connected with a low-expansion alloy 11 and a high-expansion alloy 12 by soldering or the like is used for a juxtaposedly joined alloy 6. The alloy 6 has a springy property in the vertical direction to the tube axis of a cathode-ray tube, i.e., in the radial direction DX, the fixing point 9 of a frame 3 and the alloy 6 and the fixing point 10 of a shadow mask 1 and the alloy 6 can have the free positional relationship in the radial direction to the tube axis. On the other hand, the positional adjustment of the quantity caused by the temperature change of the mask 1 is performed by the bimetal action in the tube axis direction DY. When the mask 1 is expanded via the heating by radiation, restriction is rarely applied in the radial direction to the tube axis which is the expansion direction of the mask 1 and the expansion direction of the frame 3. The positional adjustment is properly performed by the alloy 6 to the tube axis direction which is the positional adjustment direction.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a shadow mask structure for a color picture tube.

[Conventional technology]

Conventionally, this type of shadow mask structure has a large number of microholes arranged in order to select and irradiate the three color phosphors formed on the inner surface of the picture tube panel with the corresponding electron beams. is used. ' As shown in Fig. 4, the shadow mask structure includes a shadow mask 1 in which a large number of microscopic holes are arranged for color sorting, and a shadow mask 1 that is fixed by welding or other methods to increase its strength. Frame 7 and the above shadow mask 1
A spring 4 is used to fix the mask frame assembly, which is a combination of a frame 7 and a frame 7, to the panel 2 on which a fluorescent film is formed while keeping a constant distance therebetween, and a spring 4 is used to fix the mask frame assembly, which is a combination of the It is composed of a bimetal 8 which has the function of adjusting the distance between the two surfaces of the phosphor 1 and appropriately correcting the relationship between the electron beams irradiated onto the phosphor.

The most numerical method for adjusting the position of the shadow mask 1 against thermal expansion is to fix the bimetal 8 between the frame 7 and the spring 4 by means such as welding.

[Problem to be solved by the invention]

In the conventional shadow mask tank described above, a bimetal with a position adjustment function and a spring are interposed between the frame and the panel, so the electron beam collides with the shadow mask and generates heat, causing the shadow mask to undergo thermal expansion. Even if the position adjustment operation is started, it takes several tens of minutes because the heat generated by the shadow mask is transmitted through the frame, which has a large heat capacity, and then to the bimetal.

For this reason, the electron beam that passes through the shadow mask for several minutes to several tens of minutes after irradiation with the electron beam may be misaligned with respect to the corresponding phosphor, and even when a low expansion material is used as the shadow mask material, Because the thermal expansion of the frame lags behind the thermal expansion of the shadow mask, or because the thermal expansion coefficient of the shadow mask and the thermal expansion coefficient of the frame are different, the shadow mask is restrained by the frame and the curvature of the shadow mask changes, causing the same problem as above. This results in a significant positional shift of the electron beam, which has the drawback of impairing the color purity of the video screen and disrupting white uniformity.

An object of the present invention is to provide a shadow mask structure for a color picture tube with good color purity and white uniformity on a video screen.

[Means to solve the problem]

The present invention provides a color image-receiving image comprising a panel, a fluorescent film formed on the inner surface of the panel, a shadow mask arranged at regular intervals on the inner surface of the panel, and a frame for supporting and reinforcing the shadow mask. In the pipe shadow mask structure, the shadow mask and the frame are fixed via a component made of a resilient material.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a main part of a first embodiment of the present invention.

As shown in FIG. 1, the thin plate parallel metal 6 is interposed between the shadow mask 1 and the frame 3.
Directly receiving heat conduction and radiation from the source causes a change in shape, causing the shadow mask 1 to change! [11 and adjust the position.

FIGS. 2(a) and 2(b) are a detailed side view and a cross-sectional view of the peripheral part of the metal bond in the first embodiment of the present invention.

In the first embodiment of the present invention, as shown in FIGS. 2(a) and 2(b), a low expansion material alloy 11 and a high expansion material alloy 12 are joined in parallel by a method such as welding as a parallel joint metal 6. Use materials.

The above-mentioned ordinary joint 6 has a spring property in the direction perpendicular to the tube axis of the picture tube, that is, in the radial direction DX, and has a fixed point 9 between the frame 3 and the ordinary joint 6, and a fixed point between the shadow mask 1 and the ordinary joint 6. The positional relationship with 10 can take any position in the radial direction with respect to the tube axis. On the other hand, in the tube axis direction DY, the position of the shadow mask 1 is adjusted by a bimetal action according to the temperature change, and in the rotation direction DZ about the tube axis, it is restrained.

In the above configuration, when the shadow mask 1 expands due to heat generated by irradiation with the electron beam, it is hardly restrained in the radial direction with respect to the tube axis, which is the expansion direction of the shadow mask 1 and the expansion direction of the frame 3. On the other hand, with respect to the main direction of canal narrowing, which is the position adjustment direction, it is adjusted to an appropriate position by the parallel joint 6.

FIGS. 3(a) and 3(b) are a detailed side view and a sectional view of the side portion of the spring material layer according to the second embodiment of the present invention.

In the second embodiment of the present invention, as shown in FIGS. 3(a) and 3(b), when the material used for the shadow mask 21 is a low-expansion metal, no position adjustment function is required, so the frame By interposing the spring material 13 between the frame 3 and the shadow mask 21, which absorbs the difference in thermal expansion between the frame 3 and the shadow mask 21, deformation of the shadow mask 21 can be suppressed.

〔Effect of the invention〕

As explained above, the present invention indirectly fixes the shadow mask and the frame through a component made of a springy material, thereby preventing the difference in thermal expansion coefficient between the shadow mask and the frame and the delay in heat transfer. Since the difference in the amount of thermal expansion and movement between the two can be absorbed, deformation of the shadow mask due to the difference in the amount of movement can be prevented, and as a result, there is an effect of maintaining the color purity and white uniformity of the video screen.

In addition, by using a material for the spring component that changes its shape in response to temperature changes and corrects color shift due to thermal expansion of the shadow mask, the heat generated by the shadow mask is directly transmitted to the material. By quickly responding to the thermal expansion of the shadow mask and adjusting its position, the initial movement of the electron beam, which occurs for several minutes to several tens of minutes after electron beam irradiation, can be stopped and shortened. As a result, it has the effect of maintaining the color purity and white uniformity of the video screen.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main part of the first embodiment of the present invention, and FIG. 2 (
a>, (b) are detailed side views and cross-sectional views of the peripheral part of the normal joint metal of the first embodiment of the present invention, and FIG. 3 (a>, (b) are the spring material of the second embodiment of the present invention Detailed side view and sectional view of the layer side portion, and FIG. 4 is a sectional view of an example of a conventional shadow mask structure. 1... shadow mask, 2... panel, 3... frame, 4...・Spring, 5... Stud bottle,
6... Ordinary joint metal, 7... Frame, 8... Bimetal, 9... Frame side welding point, 10... Mask side welding point, 1 ],... Low expansion material alloy, 12 ...High expansion material alloy, 13...Spring material, 21...Shadow mask.

Claims (1)

[Claims] A shadow mask structure for a color picture tube that includes a panel, a fluorescent film formed on the inner surface of the panel, a shadow mask arranged at regular intervals on the inner surface of the panel, and a frame that supports and strengthens the shadow mask. 2. A shadow mask structure for a color picture tube, characterized in that the shadow mask and the frame are fixed via a component made of a springy material.