JPH10289667A - Color picture tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color picture tube in which resonance of an inner shield due to external shock or vibration is hardly generated and noises or slip-off particles are not generated. SOLUTION: This picture tube is supported by a stud pin 8 at which a substantially rectangular shadow mask 5 is provided at a corner part of a panel 2 and a frame holder 20 fixed to a mask frame 7, and a substantially rectangular cylinder shaped inner shield 25 is disposed inside of a large-diameter part of a funnel 3. In this case, a mounting part 27 is provided at the corner part of the inner shield 25, and that mounting part is fixed to a fixing part 21 of the frame holder 20 not so as to come into contact with the mask frame 7.

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 having an improved inner shield mounting structure for preventing the influence of geomagnetism on an electron beam.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, a color picture tube has an envelope comprising a substantially rectangular panel 2 provided with a skirt portion 1 at a peripheral portion and a funnel-shaped funnel 3. A phosphor screen 4 composed of a three-color phosphor layer in the form of a dot or a stripe is provided on the inner surface of the substrate 2, and a substantially rectangular shadow mask 5 is disposed inside the phosphor screen 4 at a predetermined distance from the phosphor screen 4. I have. The shadow mask 5 has a mask body 6 having a large number of electron beam passage holes formed on a surface facing the phosphor screen 4.
And a mask frame 7 having an L-shaped cross section attached to the periphery of the mask body 6, stud pins 8 provided at each corner of the panel 2, and stud pins 8 fixed to the mask frame 7. It is supported by a frame holder 9 which is locked to the pin 8. On the other hand, an electron gun 11 is provided in the neck 10 of the funnel 3. Then, the three electron beams emitted from the electron gun 11 are changed to 1
2B, 12G, 12R are deflected by a deflecting device 13 mounted outside the funnel 3, and the phosphor screen 4 is horizontally and vertically scanned through a shadow mask 5 to form a structure for displaying a color image. I have.

Further, in such a color picture tube, a rectangular cylindrical inner shield 15 is generally arranged inside the large diameter portion of the funnel 3 in order to prevent the influence of geomagnetism on the three electron beams 12B, 12G and 12R. I have. Conventionally, the inner shield 15 is attached to the mask frame 7, and as an attachment structure, as shown in FIG. 4, the long side and the short side of the inner projecting portion 16 of the mask frame 7 and the flange portion 17 of the inner shield 15. A plurality of openings are formed coaxially on the long side and the short side, respectively, and a locking pin 18 is inserted into these openings and fixed.

[0004]

As described above, in the color picture tube, the inner shield is disposed inside the large diameter portion of the funnel in order to prevent the influence of geomagnetism on the three electron beams. A plurality of holes are formed coaxially in the inner overhang portion of the mask frame of the shadow mask and the flange portion of the inner shield as a mounting structure of the inner shield, and locking pins are inserted into these holes and fixed. There is.

However, when the inner shield is directly attached to the inner overhang of the mask frame as described above, the mask frame and the inner shield accurately contact the inner overhang and the flange uniformly over the entire circumference. Because it is difficult to manufacture, there is a portion that does not contact between the inner overhang portion and the flange portion.

On the other hand, in a color picture tube, when an external shock or a sound vibration from a speaker is applied, the shock or vibration is transmitted to an inner shield via a panel, a stud pin, a mask frame, and the like, and the inner shield has a specific frequency. Resonates due to shock or vibration in the area, generating noise. In particular, if there is a portion that does not contact between the inner protruding portion and the flange portion as described above, an abnormal sound that causes discomfort to the viewer is generated due to the resonance.

If there is a portion that does not come into contact between the inner overhang portion of the mask frame and the flange portion of the inner shield as described above, the inner overhang portion and the flange due to the resonance due to the impact or vibration when the inner shield is attached. Rubbing at the point of contact with the part, the oxide film etc. formed on the surface of the mask frame and inner shield fall off, and the fallen particles clog the electron beam passage holes of the shadow mask, causing screen defects In addition, it causes problems such as the adhesion to the electrode of the electron gun and the deterioration of the withstand voltage characteristic.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and makes it difficult for the inner shield to resonate even when an external impact or vibration is applied to the color picture tube, so that noise and falling particles are not generated. It is intended to constitute a color picture tube.

[0009]

A substantially rectangular shadow having an envelope consisting of a substantially rectangular panel and a funnel-shaped funnel, and having a mask frame attached to the periphery of a mask body inside the panel. The mask is supported by stud pins provided at the corners of the panel and a frame holder fixed to the mask frame and locked to the stud pins, and a substantially rectangular cylindrical inner shield is disposed inside the large diameter portion of the funnel. In a color picture tube, a mounting part is provided at the corner of the inner shield,
The mounting portion was fixed to a fixing portion of a frame holder fixed to the mask frame so that the inner shield did not contact the mask frame.

The fixing portion of the frame holder extends from the funnel side end of the mask frame in the direction opposite to the mask body, and the mounting portion of the inner shield extends in the direction opposite to the mask body. It was formed in a folded shape to hold the portion.

Further, coaxial through-holes are provided in the extending portion of the frame holder extending in the direction opposite to the mask body and the mounting portion of the inner shield, and the inner shield is formed by the locking pins inserted in these through-holes. It was fixed to the fixed part of the holder.

[0012]

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

FIG. 1 shows a color picture tube which is one embodiment of the present invention. This color picture tube has an envelope composed of a substantially rectangular panel 2 provided with a skirt 1 at the periphery and a funnel-shaped funnel 3. On the inner surface of the panel 2, a phosphor screen 4 composed of a three-color phosphor layer in a dot or stripe shape is provided. A substantially rectangular shadow mask 5 is arranged inside the phosphor screen 4 at a predetermined distance from the phosphor screen 4. This shadow mask 5
Is a substantially rectangular mask body 6 having a large number of electron beam passage holes formed on a surface facing the phosphor screen 4.
A stud pin 8 provided at each corner of the panel 2, comprising a substantially rectangular mask frame 7 having an L-shaped cross section and having an inner overhang 16 attached to the periphery of the mask body 6; It is fixed to the mask frame 7 and is supported by a frame holder 20 which is locked to each of the stud pins 8.

The frame holder 20 includes a fixing portion 21 fixed to the mask frame 7, a locking portion 22 provided with an engaging hole for engaging with the stud pin 8, and the fixing portion 21 and the locking portion 22. It is formed in a substantially wedge shape including a connecting portion 23 inclined and connected to the fixing portion 2 of the frame holder 20 in this embodiment.
Reference numeral 1 extends along the side surface of the mask frame 7 from the opposite end of the mask body 6 toward the neck 10 of the funnel 3, and an opening for attaching an inner shield described later is formed in the extension. ing.

On the other hand, in the neck 10 of the funnel 3,
An electron gun 11 for emitting three electron beams 12B, 12G, and 12R is provided. An inner shield 25 made of a magnetic material for preventing the influence of geomagnetism on the three electron beams 12B, 12G and 12R is arranged inside the large diameter portion of the funnel 3. This inner shield 25 is
As shown in FIG. 2, it is formed in a substantially rectangular cylindrical shape, and a flange portion 26 is provided at one end thereof. In particular, in this embodiment, as shown in FIG.
At each corner of No. 6, a mounting portion 27 for mounting the inner shield 25 to the fixing portion of the frame holder is integrally provided. In the illustrated example, the mounting portion 27
Is formed in a folded shape having a U-shaped cross section for holding the extending portion of the fixed portion of the frame holder, and an opening 28 coaxial with the opening formed in the extending portion of the frame holder is formed on the opposite side surface. Is formed.

The inner shield 25 is engaged so as to clamp the extension of the fixing portion 21 of the frame holder 20 with the opposite side surface of the attachment portion 27 formed in the folded shape, and the opposite side surface of the attachment portion 27. The frame is fixed by inserting a locking pin 29 into an opening formed in an extension of the fixing portion 21 of the frame holder 20. In this case, the inner shield 25 is fixed by the locking pin 29 so that a fixed gap 30 is provided between the inner protruding portion 16 of the mask frame 7 and the flange portion 26 of the inner shield 25.
Mounted to allow

As described above, the fixing portion 21 of the wedge-shaped frame holder 20 supporting the shadow mask 5 is
It extends in the zero direction (opposite direction of the mask body 6), and on the other hand, a folded mounting portion 27 is provided on the inner shield 25, and the extended portion of the fixed portion 21 and the mounting portion 27 of the inner shield 25 are engaged. When the inner shield 25 is attached to the inner frame 25, a predetermined gap 3 is formed between the inner protruding portion 16 of the mask frame 7 and the flange portion 26 of the inner shield 25.
0, and the inner shield 25
Can be mounted so that they do not come into contact with each other, so that even if impact or vibration is applied to the color picture tube, contact between the mask frame 7 and the inner shield 25 can be avoided and noise generation can be reduced.

In addition, clogging of the electron beam passage hole of the shadow mask due to particles falling off due to contact and friction between the mask frame 7 and the inner shield 25,
Deterioration of withstand voltage characteristics can be reduced.

Further, even if the inner shield 25 is heated by the collision of the over-deflected electron beam, since the inner shield 25 is not in contact with the mask frame 7, the heat conduction from the inner shield 25 to the mask frame 7 is low. Landing deviations of the electron beams 12B, 12G, and 12R with respect to the three-color phosphor layer due to an increase in the temperature of the mask frame 7 can be reduced.

In the above-described embodiment, the attachment portion of the inner shield is formed in a folded shape. However, the attachment portion may have any structure as long as it can be fixed to the extension of the fixing portion of the frame holder. A shape other than the shape may be used.

In the above-described embodiment, the inner shield and the frame holder are fixed using the locking pin. However, the inner shield and the frame holder may be fixed by welding.

[0022]

According to the present invention, a substantially rectangular shadow mask having an envelope composed of a substantially rectangular panel and a funnel-shaped funnel and having a mask frame attached to the periphery of the mask body inside the panel is provided. In a color picture tube which is supported by a stud pin provided at a corner portion and a frame holder fixed to a mask frame and locked to the stud pin, and having a substantially rectangular cylindrical inner shield disposed inside a large diameter portion of the funnel. A mounting portion is provided at a corner portion of the inner shield, and the mounting portion is fixed to a fixing portion of a frame holder fixed to the mask frame so that the inner shield does not contact the mask frame. Extend the mask frame from the funnel side end in the direction opposite to the mask body, and The attachment portion of the nurse shield is formed in a folded shape to sandwich the extension portion of the fixed portion extending in the opposite direction of the mask body, and further, the extension portion of the frame holder extending in the opposite direction of the mask body and When coaxial through holes are provided in the mounting part of the inner shield and the inner shield is fixed to the fixed part of the frame holder by the locking pins inserted into these through holes, the inner projection of the mask frame and the flange part of the inner shield With a certain gap between them, the inner shield can be mounted so that it does not contact the mask frame.Even if shock or vibration is applied to the color picture tube, the mask frame and the inner shield are prevented from contacting each other, generating noise. Can be reduced.

Further, it is possible to reduce clogging of the electron beam passage hole of the shadow mask and deterioration of the withstand voltage characteristics due to particles falling off due to the contact and friction between the mask frame and the inner shield.

Further, even if the inner shield is heated by the collision of the over-deflected electron beam, since the inner shield is not in contact with the mask frame, heat conduction from the inner shield to the mask frame is low, and the temperature of the mask frame rises. , The landing deviation of the electron beam with respect to the three-color phosphor layer can be reduced.

[Brief description of the drawings]

FIG. 1A is a diagram showing a configuration of a color picture tube according to an embodiment of the present invention, and FIG. 1B is a diagram showing a mounting structure of an inner shield thereof.

FIG. 2 is a partially cutaway view of the structure of the inner shield.

FIG. 3 is a diagram showing a configuration of a conventional color picture tube.

FIG. 4 is a diagram showing a mounting structure of an inner shield of a conventional color picture tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 2 ... Panel 3 ... Funnel 5 ... Shadow mask 6 ... Mask main body 7 ... Mask frame 8 ... Panel pin 16 ... Inner projection 20 ... Frame holder 21 ... Fixed part 25 ... Inner shield 26 ... Flange 27 ... Mounting part 29 ... Lock Pin 30 ... gap

Claims (3)

[Claims] 1. A substantially rectangular shadow mask comprising an envelope comprising a substantially rectangular panel and a funnel-shaped funnel, wherein a mask frame is attached to the periphery of a mask body inside the panel. And a frame holder fixed to the mask frame and fixed to the mask frame and locked by the stud pin, and supported by a substantially rectangular cylindrical inner shield inside the large-diameter portion of the funnel. In the color picture tube, a mounting portion is provided at a corner portion of the inner shield, and the mounting portion is fixed to a fixing portion of the frame holder fixed to the mask frame so that the inner shield does not contact the mask frame. A color picture tube. 2. A fixing portion of the frame holder extends from a funnel side end of the mask frame in a direction opposite to the mask body, and a mounting portion of the inner shield extends from a fixing portion extending in a direction opposite to the mask body. 2. The color picture tube according to claim 1, wherein the color picture tube is formed in a folded shape for holding the projection. 3. A coaxial through-hole is provided in an extension portion of the frame holder extending in a direction opposite to the mask body and a mounting portion of the inner shield, and the inner shield is formed by a locking pin inserted into these through-holes. 3. The color picture tube according to claim 2, wherein said color picture tube is fixed to a fixing portion of said frame holder.