JPH08329850A - Color cathode ray tube - Google Patents

Abstract

(57) [Summary] [Object] To provide a color cathode ray tube capable of moving a shadow mask structure 7 along a tube axis by a desired length in accordance with thermal expansion of the shadow mask structure 7. A shadow mask structure 7 comprising a panel portion having a color fluorescent surface, a neck portion accommodating an electron gun, and a funnel portion connecting the panel portion and the neck portion, and comprising a shadow mask 6 stretched. In the color cathode ray tube in which the shadow mask 6 is attached to face the color fluorescent surface, the shadow mask structure 7 is
For welding mask welding bar members 19a, 19b, support arm members 20a, 20b bridge-fixed to the bar members 19a, 19b, and first spring suspension for connecting the bar members 19a, 19b to a fixing portion in the panel portion. Member 18
a, 18b and second spring suspension members 21a, 21b having a laminated bimetal part 21c for connecting the arm members 20a, 20b to a fixed part in the panel part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color cathode ray tube, and more particularly, when the shadow mask structure rises in temperature due to electron beam bombardment and the shadow mask structure is thermally expanded, The present invention relates to a color cathode ray tube that corrects the occurrence of a shift in the relative position between the phosphor of each color and the electron beam passage hole of the shadow mask.

[0002]

2. Description of the Related Art In general, a color cathode ray tube is a vacuum envelope comprising a panel portion having a color fluorescent surface on its inner surface, a neck portion accommodating an electron gun, and a funnel portion connecting the panel portion and the neck portion. A mask frame is attached to the inside of the panel portion, and a shadow mask is stretched over the mask frame so that the shadow mask is arranged to face the color fluorescent surface. The shadow mask has many electron beam passage holes, and the three electron beams projected from the electron gun pass through one electron beam passage hole of the shadow mask and are red and green provided on the color fluorescent surface. , The respective paths of the three electron beams are selectively controlled so as to share the respective blue phosphors and project them.

Here, the shadow mask is usually made of iron (F).
e) or a metal material having a small coefficient of thermal expansion, such as iron-
A thin film of a nickel (Fe-Ni) alloy is formed into a substantially dome shape, and a large number of electron beam passage holes each having a round shape, a rectangular shape, or a blind shape are regularly provided, and a shadow mask. The opposite peripheral edge portions of the above are stretched over the mask frame attached to the inner surface of the panel portion. In this case, the arrangement positions of the many electron beam passage holes in the shadow mask respectively correspond to the arrangement positions of the three-color phosphors on the color fluorescent surface on the inner surface of the panel portion.

Further, the shadow mask structure may be bombarded by an electron beam during operation of the color cathode ray tube, which may raise the temperature of the shadow mask structure and cause thermal expansion. And when the shadow mask structure causes thermal expansion,
The positional relationship between the arrangement positions of the many electron beam passage holes of the shadow mask, which had been aligned up to that point, and the arrangement positions of the phosphors of each color on the color fluorescent surface was broken, and a predetermined color could be formed on the color fluorescent surface. Disappear.

In particular, in recent years, it has been necessary to improve the accuracy of the displayed image as the demand for a color cathode ray tube for displaying a high-definition image has increased. Therefore, the electron beam accompanying the thermal expansion of the shadow mask structure is required. The deviation of the positional relationship between the arrangement position of the passage hole and the arrangement position of the fluorescent body of each color cannot be ignored, and it becomes necessary to suppress the deviation of the landing position of the electron beam on the color fluorescent surface with high accuracy. It was

Due to the thermal expansion of the shadow mask structure, the positional relationship between many electron beam passage holes and many three-color fluorescent bodies is displaced with respect to the tube axis of the color cathode ray tube. It is known to occur so as to spread radially in a direction perpendicular to the tube axis. On the other hand, the electron beam passing through each electron beam passage hole of the shadow mask is projected from an electron gun arranged at a position close to the tube axis, travels along the tube axis, and then is deflected by the deflection coil with respect to the tube axis. Radial deflection is also well known. From such a point of view, when the shadow mask structure undergoes thermal expansion, if the position of the shadow mask is moved along the tube axis by a predetermined length depending on the degree of thermal expansion, the shadow mask structure will be It is already known that the positional relationship between many electron beam passage hole arrangement positions and many three-color fluorescent substance arrangement positions due to thermal expansion can be corrected.

By the way, a known means for correcting the positional relationship between the arrangement positions of many electron beam passage holes and the arrangement positions of many three-color fluorescent bodies due to the thermal expansion of the shadow mask structure (hereinafter Is a known beam landing correction means), in which a plurality of spring suspension members having a butt bimetal portion formed by abutting two metal plates having different thermal expansion coefficients are joined to a mask frame, It is mounted and fixed inside the panel by a plurality of spring suspension members. Here, the butt bimetal is obtained by welding the high thermal expansion material and the low thermal expansion material in the width direction with respect to the plate thickness, that is, the plate thickness of the high thermal expansion material and the low thermal expansion material and the butt bimetal. The plate thickness is the same, and the weld is generally a line. On the other hand, the laminated bimetal is obtained by welding the high thermal expansion material and the low thermal expansion material in the plate thickness direction, that is, the plate thickness of the welded bimetal is the material of the high thermal expansion material and the low thermal expansion material. And the weld is generally a face.

According to this structure, when the temperature of the shadow mask structure rises and thermal expansion occurs, the heat of the shadow mask is transmitted to the plurality of spring suspension members through the mask frame, and the butt bimetal portions of the spring suspension members are connected. By deforming, the mask frame and the shadow mask are moved slightly along the tube axis of the color cathode ray tube in the direction of the fluorescent surface, and the positions of many electron beam passage holes and the positions of many three-color fluorescent bodies are arranged. The deviation of the positional relationship with is corrected.

[0009]

The known beam landing correction means has a positional relationship between the arrangement positions of many electron beam passage holes and the arrangement positions of many three-color fluorescent bodies due to the thermal expansion of the shadow mask structure. Although it is an effective means of correcting the deviation of the above, since the butt bimetal parts are used for the plurality of spring suspension members, the change range cannot be made large. In particular, in a shadow mask of a type in which the shadow mask is stretched by a mask frame (tension is applied), when the heat capacity of the mask frame is relatively large, a temperature difference occurs depending on the location of the mask frame. Therefore, there is a difference in the way the spring suspension member warms up, and the deformation of the butt bimetal part is small at the lower temperature of the spring suspension member.Therefore, both the mask frame and the shadow mask have a sufficient length along the tube axis. There is a problem that it cannot be moved by the amount.

The present invention solves the above-mentioned problems.
The purpose is that, when the heat capacity of the mask frame is relatively large, the shadow mask can be moved by a desired length along the tube axis when the shadow mask mounted by applying tension is thermally expanded. It is to provide a color cathode ray tube.

[0011]

In order to achieve the above object, the present invention provides a panel section having a color fluorescent surface on the inner surface, a neck section accommodating an electron gun, the panel section and the neck section. Consisting of a funnel portion connected to each other, a shadow mask structure is mounted inside the panel portion, and the shadow mask structure is a structure in which a shadow mask is stretched.
In the color cathode ray tube in which the shadow mask is arranged to face the color fluorescent surface, the shadow mask structure includes the shadow mask, and a pair of mask welding bar members to which opposite peripheral edges of the shadow mask are welded. A pair of substantially U-shaped support arm members bridgingly fixed to the pair of mask welding bar members, and a first spring suspension member for connecting the pair of mask welding bar members to a fixing portion in the panel portion And a second spring suspension member that couples the pair of support arm members to a fixed portion in the panel portion. The second spring suspension member includes two types of metal plates having different thermal expansion coefficients in the plate thickness direction. Means having a laminated bimetal portion welded together.

[0012]

According to the above means, two metal plates are bonded to the pair of substantially U-shaped support arm members bridgingly fixed to the pair of mask welding bar members in the mask frame. Since the second spring suspension member having the mating bimetal part is coupled, the heat of the shadow mask is transferred through the pair of mask welding bar members, and the heat is transmitted between the mask welding bar member and the pair of support arm members. Even if there is a temperature difference, when the heat from the shadow mask is transferred to the pair of support arm members, the bonded bimetal part will be bent and deformed, and the mask frame will be colored with fluorescence along the tube axis. It becomes possible to move in the plane direction.

As described above, according to the above-mentioned means, the movement of the mask frame can take a sufficient length of movement of the mask frame by using the laminated bimetal portion.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing the schematic construction of an embodiment of a color cathode ray tube according to the present invention.

In FIG. 1, 1 is a panel portion, 2 is a funnel portion, 3 is a neck portion, 4 is a face plate, 5 is a color fluorescent surface, 6 is a shadow mask, 7 is a mask frame, 8 is a deflection yoke, and 9 is a deflection yoke. Is an electron gun, 10 is a purity adjusting magnet, 11 is a center beam static convergence adjusting magnet, 12 is a side beam static convergence adjusting magnet, 13 is a magnetic shield, 14 is an embedded pin, 15 is a reinforcing band, and 16 is a center electron. Beam, 17 is side electron beam, 21
Reference numerals a and 21b are second spring suspension members.

The glass vacuum envelope constituting the color cathode ray tube has a panel portion 1 arranged on the front side, a neck portion 3 accommodating an electron gun 9, a panel portion 1 and a neck portion 3. And a funnel portion 2 which connects them and is arranged in the middle. The panel unit 1 has a face plate 4 on the front surface, and a color fluorescent surface 5 is arranged and formed on the inner surface of the face plate 4. A plurality of embedding pins 14 are embedded in the side surface portion of the panel portion 1, and the mask frame 7 is attached to the panel portion 1 by the second spring suspension members 21a and 21b respectively coupled to the embedding pins 14 and the mask frame 7. It is fixedly placed inside. The shadow mask 6 is stretched by a mask frame 7 having a relatively large heat capacity, and is arranged so as to face the color fluorescent surface 5. A reinforcing band 15 is attached to the outer peripheral surface of the panel portion 1, a magnetic shield 13 is provided inside the joint portion between the panel portion 1 and the funnel portion 2, and a deflection yoke 8 is provided outside the joint portion between the funnel portion 2 and the neck portion 3. Is provided. A purity adjusting magnet 10, a center beam static convergence adjusting magnet 11 and a side beam static convergence adjusting magnet 12 are arranged side by side outside the neck portion 3, and three electron beams 16 projected from an in-line type electron gun 9 are arranged. , 17 are configured to reach the color fluorescent surface 5 through an electron beam passage hole (not shown) of the shadow mask 6 after being deflected in a predetermined direction by the deflection yoke 8.

In this case, the operation of the color cathode ray tube having the above-mentioned structure, that is, the image display operation is the same as the image display operation of the known color cathode ray tube, and such display operation is already known. The description of the image display operation of the color cathode ray tube is omitted.

FIG. 2 is a perspective view showing an example of the structure of the shadow mask 6 and the mask frame 7 used in the color cathode ray tube shown in FIG. 1, and FIG. 3 shows the second spring suspension member. It is an enlarged block diagram which shows an example of a structure.

2 and 3, 18a and 18b are first spring suspension members, 18c is a base plate portion of the first spring suspension members 18a and 18b, and 18d.
Is a butt bimetal spring portion, 19a and 19b are a pair of mask welding bar members, 20a and 20b are a pair of substantially U-shaped support arm members, 21c is a laminated bimetal portion of the second spring suspension members 21a and 21b, Two
Reference numeral 1d is the same L-shaped portion, 21e is the same spring portion, and other same constituent elements as those shown in FIG. 1 are denoted by the same reference numerals.

The mask frame 7 is provided with a pair of mask welding bar members 19 having an L-shaped cross section and arranged in parallel with each other.
a, 19b and both ends thereof are welded to a pair of mask welding bar members 19a, 19b, respectively, and a pair of substantially U-shaped support arms for fixing the pair of mask welding bar members 19a, 19b in a parallel spaced arrangement state. First spring suspension members 18a, 1 connected to members 20a, 20b and a pair of mask welding bar members 19a, 19b, respectively, at substantially intermediate portions thereof.
8b and a second spring suspension member 21 respectively coupled to substantially intermediate portions of the pair of support arm members 20a and 20b.
It consists of a and 21b. In addition, the peripheral edges of the shadow mask 6 facing each other are welded to the pair of mask welding bar members 19 a and 19 b, and the shadow mask 6 is stretched by the mask frame 7. First spring suspension member 18
Each of a and 18b is composed of a base plate portion 18c and a butt bimetal spring portion 18d, of which one end edge of the base plate portion 18c is welded to the side surfaces of the mask welding bar members 19a and 19b, and the other of the base plate portion 18c. The edge is welded to one end surface of the butt bimetal spring portion 18d, and the other end of the butt bimetal spring portion 18d is joined to the embedded pin 14 on the side surface of the panel portion 1. The second spring suspension member 21a,
Reference numeral 21b includes a laminated bimetal portion 21c, an L-shaped portion 21d, and a spring portion 21e.
One end edge of the laminated bimetal part 21c is the support arm member 2
0a, 20b is welded to the upper surface, and the laminated bimetal part 2
The other end edge of 1c is welded to one surface of the L-shaped portion 21d,
The other surface of the L-shaped portion 21d is welded to one end surface of the spring portion 21e, and the other end portion of the spring portion 21e is joined to the embedded pin 14 on the side surface of the panel portion 1.

In this case, the second spring suspension member 21
a and 21b are, as the laminated bimetal part 21c, one metal plate having a high thermal expansion property, for example, SUS304 having a thermal expansion coefficient of 0.000017, and one metal plate having a low thermal expansion property, for example, a thermal expansion coefficient. Is 0.0000
01 amber material (Fe-Ni36) is laminated. The pair of mask welding bar members 19a and 19b have a thermal expansion coefficient of 0.0000, for example.
11 of 13 chrome steel.

The mask frame 7 having the above-described structure functions as follows.

During operation of the color cathode ray tube, the electron beam 1
When 6 and 17 hit the shadow mask 6, the temperature of the shadow mask 6 rises. The thermal expansion due to the temperature rise at this time is absorbed by the tension applied to the shadow mask 6. At this time, the heat generated in the shadow mask 6 is transferred to the pair of mask welding bar members 19a and 19b where the peripheral edge of the shadow mask 6 is welded, and the temperature of the pair of mask welding bar members 19a and 19b is increased. To rise and thermally expand. Along with this, the shadow mask 6 apparently appears to have undergone thermal expansion. Next, the heat transferred to the pair of mask welding bar members 19a and 19b is a pair of substantially U-shaped support arm members 20a and 20b whose both ends are welded to the pair of mask welding bar members 19a and 19b. Is transferred to the pair of support arm members 20a and 20b to raise the temperature and thermally expand.

At this time, the pair of mask welding bar members 1
The heat transferred to 9a and 19b is the first spring suspension member 1
The abutting bimetal spring portion 18d is slightly curved by the heat transmitted to the abutting bimetal spring portion 18d.
Since one end of the shadow mask structure 7 is coupled to the embedded pin 14 of the panel part 1, the distance between the shadow mask structure 7 and the panel part 1 is adjusted according to the degree of the curvature, and the thermal expansion of the shadow mask structure 7 is prevented. It becomes possible to correspond. Further, the heat transferred to the pair of mask welding bar members 19a and 19b is transferred to the second via the pair of support arm members 20a and 20b.
Heat is also transferred to the spring suspension members 21a and 21b. At this time, the bonded bimetal part 21c is moved by the heat transferred to the second spring suspension members 21a and 21b, so that
As shown by the dotted line at the bottom of the support arm member 2
0a, 20b, that is, the welding bimetal portion 21c is slightly curved upward from the one end surface of the laminated bimetal portion 21c, but the other end surface of the laminated bimetal portion 21c is L
Since it is connected to the embedding pin 14 of the panel portion 1 with the character-shaped portion 21d and the spring portion 21e interposed therebetween, the pair of support arm members 20a, 20b are formed depending on the degree of the bending.
Is extruded toward the lower side of FIG. 2, that is, toward the color fluorescent surface 5, and at the same time, the pair of support arm members 20a,
The shadow mask 6 moves in the direction of the color fluorescent surface 5 along the tube axis through the pair of mask welding bar members 19a and 19b to which both ends of 20b are welded. Due to this movement, the displacement of the positional relationship between the arrangement positions of many electron beam passage holes and the arrangement positions of many three-color fluorescent bodies due to the thermal expansion of the shadow mask structure 7 is effectively corrected.

As described above, according to the color cathode ray tube of the present embodiment, even if the shadow mask structure 7 thermally expands during the operation of the color cathode ray tube, the color fluorescent surface is slightly increased depending on the degree of the thermal expansion. Since it will move to the 5 side,
It is possible to correct the deviation of the positional relationship between the arrangement positions of many electron beam passage holes and the arrangement positions of many phosphors of three colors, and it is possible to always obtain a display image with no color deviation.

According to the color cathode ray tube of this embodiment, the pair of mask welding bar members 19a and 19b are provided with
First spring suspension members 18a, 18b having a butt bimetal spring portion 18d with a relatively small amount of deformation
While the pair of support arm members 20a, 20a
On the b side, a bonded bimetal part 21 with a relatively large amount of deformation
Since the second spring suspension members 21a and 21b having c are coupled, heat transfer from the shadow mask 6 is good, that is, on the side of the pair of mask welding bar members 19a and 19b where the temperature becomes high. The amount of movement of the butt bimetal spring portion 18d and the heat transfer from the shadow mask 6 are poor, that is, the bonding bimetal portion 21c on the side of the pair of support arm members 20a and 20b where the temperature remains low. The amount of movement can be made substantially the same, and as a result, the moving length of the shadow mask structure 7 can be sufficiently taken.

In the above-mentioned embodiments, the example in which SUS304 and amber material are used as the constituent material of the laminated bimetal part 21c in the second spring suspension members 21a and 21b has been described. Of course, this is merely an example, and other similar constituent materials may of course be used.

[0029]

As described above in detail, according to the present invention, even if the shadow mask structure thermally expands during the operation of the color cathode ray tube, the shadow mask structure is slightly expanded depending on the degree of the thermal expansion. Since it moves to the color fluorescent surface side, the displacement of the positional relationship between the arrangement positions of many electron beam passage holes and the arrangement positions of many three-color fluorescent bodies is automatically corrected, and there is always no color displacement. There is an effect that a display image can be obtained.

According to the present invention, the pair of mask welding bar members is connected to the first spring suspension member provided with the butt bimetal part having a relatively small deformation, and the pair of support arm members are connected to each other. Since the second spring suspension member having the bonded bimetal portion that is relatively large in deformation is coupled, it is possible to prevent the temperature change of the butt bimetal portion on the pair of mask welding bar members side where the heat transfer from the shadow mask is good. It is possible to execute the bending operation amount accompanying the temperature change of the bonding bimetal part on the pair of supporting arm members side where the heat transfer from the shadow mask is slow, almost the same. The effect is that it can be moved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic configuration of an embodiment of a color cathode ray tube according to the present invention.

2 is a perspective view showing an example of a configuration of a shadow mask and a mask frame used in the color cathode ray tube shown in FIG.

FIG. 3 is an enlarged configuration diagram showing an example of a configuration of a second spring suspension member.

[Explanation of symbols]

1 Panel Part 2 Funnel Part 3 Neck Part 4 Face Plate 5 Color Fluorescent Surface 6 Shadow Mask 7 Shadow Mask Structure 8 Deflection Yoke 9 Electron Gun 10 Purity Adjustment Magnet 11 Center Beam Static Convergence Adjustment Magnet 12 Side Beam Static Convergence Adjustment Magnet 13 magnetic shield 14 embedded pin 15 reinforcing band 16 center electron beam 17 side electron beam 18a, 18b first spring suspension member 18c base plate portion 18d butt bimetal spring portion 19a, 19b pair of mask welding bar members 20a, 20b A pair of character-shaped support arm members 21a, 21b Second spring suspension member 21c Laminated bimetal part 21d L-shaped part 21e Spring part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideo Tanabe 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Electronic Device Division (72) Inventor Kawa ▲ ▼ ▼ 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd. In the company

Claims (3)

[Claims] 1. A shadow mask comprising: a panel section having a color fluorescent surface on an inner surface thereof; a neck section accommodating an electron gun; and a funnel section connecting the panel section and the neck section to each other. A structure is attached, and the shadow mask structure is a structure in which a shadow mask is stretched,
In the color cathode ray tube in which the shadow mask is arranged to face the color fluorescent surface, the shadow mask structure includes the shadow mask, and a pair of mask welding bar members to which opposite peripheral edges of the shadow mask are welded. A pair of substantially U-shaped support arm members bridgingly fixed to the pair of mask welding bar members, and a first spring suspension member for connecting the pair of mask welding bar members to a fixing portion in the panel portion And a second spring suspension member that couples the pair of support arm members to a fixed portion in the panel portion, wherein the second spring suspension member has a bimetal portion obtained by bonding two metal plates together. Characteristic color cathode ray tube. 2. The second spring suspension member has a bimetal portion in which two types of metal plates having different thermal expansion coefficients are welded in the plate thickness direction, and the collar cap of the pair of support arm members is formed. The color cathode ray tube according to claim 1, wherein a bimetal type high thermal expansion material is attached to the side opposite to the light surface. 3. The color cathode ray tube according to claim 1, wherein the first spring suspension member has a bimetal portion formed by abutting two metal plates.