JP2004022509A - Cathode-ray tube and color selection mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To optimally collect mislanding of electron beams by ensuring the sufficient displacement of a color selection mechanism for collecting the mislanding to the side of a fluorescent surface. <P>SOLUTION: A cathode ray tube comprises a color selection mechanism 5 where a pair of supporting members 10, 11 forming a frame 14 are made of bimetal steel as a clad member 28, in which a high thermal expansion coefficient member 25 and a low thermal expansion coefficient member 26 are bonded together. An electrode thin plate for color selection 17 is stretched between the pair of supporting members 10, 11. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cathode ray tube and a color selection mechanism.
[0002]
[Prior art]
Conventionally, as a color selection mechanism used for a color cathode ray tube, a color selection mechanism called an aperture grill is known as shown in FIG.
As shown in the drawing, the color selection mechanism 39 includes a pair of opposing support members 41 and 42 having an L-shaped cross section and a pair of supporting members 41 supporting between the ends of the support members 41 and 42. A large number of ribbon-shaped grid bodies 46 have a large number of slit-shaped beam transmitting holes 47 between the support members 41 and 42 of a frame-shaped metal frame 45 composed of elasticity imparting members 43 and 44 having a letter shape. The color-selecting electrode thin plates 48 arranged at a predetermined pitch along the horizontal direction of the screen so as to be formed are stretched with a predetermined tension.
[0003]
The color selection mechanism 39 is disposed so as to face the color phosphor screen, and is supported by the panel pins 55 on the inner wall of the panel 37 of the cathode ray tube by three-point support or four-point support, in the illustrated example, four-point support. You. Therefore, the support springs 51 having the engagement holes 50 at the respective distal ends are welded to the four sides of the frame 45, that is, the support members 41 and 42 and the elasticity providing members 43 and 44, respectively, via the spring holder 49. The color selection mechanism 39 is mounted on the panel 37 by fitting the respective engagement holes of the support spring 51 with panel pins 55 provided at four places on the inner wall of the panel 37.
[0004]
By the way, in the cathode ray tube provided with the color selection mechanism 39 having such a configuration, the grid element body 46 generates heat by the electron beam during operation, and the heat is partially transmitted to the frame 45 so that the frame 45 thermally expands. As a result, mislanding of the electron beam occurs. That is, as shown in FIG. 9, when the pair of support members 41 and 42 thermally expand in the longitudinal direction as shown by the broken line due to the thermal influence of the frame 45, the grid element 46 follows the thermal expansion. The beam is bent, and the beam transmission hole 47 is displaced particularly in the peripheral portion. For this reason, the electron beam 53 that has passed through the predetermined beam transmitting hole 47 at the position A ₁ before thermal expansion and reached the predetermined position P ₁ on the fluorescent screen 56 is moved to the support members 41 and 42 of the frame 45. than after thermal deformation will be reached through the beam transmission holes 47 displaced to the position a _2, as indicated by the broken line 57 in the position P ₂ of the phosphor screen 56, mislanding will occur.
[0005]
Conventionally, in order to correct mislanding due to thermal expansion of the frame 45, a color drift mechanism 39 is provided with a temperature drift correction unit having a bimetal structure. As this temperature drift correction means, for example, the spring holder 49 fixed to the support members 41, 42 of the frame 45 has a bimetal structure, and the coefficient of thermal expansion is provided on the back surface of the elasticity imparting members 43, 44 by the members 43, 44. A metal member (STC plate) 54 having a large size is fixed, and a bimetal structure is used here. The spring holder 49 of the bimetal structure is formed of a bonding member of a metal member having a large coefficient of thermal expansion on the outside and a metal member having a small coefficient of thermal expansion on the inside, and has a U-shaped portion curved inward at each intermediate portion. Is provided.
In this configuration, when the frame 45 thermally expands, the color sorting mechanism 39 is displaced toward the phosphor screen 56 side by the bimetal structure to correct mislanding.
[0006]
Further, as another conventional example of the color selection mechanism, a metal having a larger thermal expansion coefficient than the support member is provided on the back surface of the pair of support members constituting the frame opposite to the surface on which the color selection electrode thin plate is stretched. A color selection mechanism in which a member is fixed to have a bimetal structure has also been proposed (see JP-A-10-255677).
Further, as another conventional example of the color selection mechanism, a pair of support members having an L-shaped cross section constituting a frame is formed by a bimetal structure in which the outside has a higher thermal expansion coefficient than the inside over the entire L-shape. A proposed color selection mechanism has also been proposed (see JP-A-2000-357466).
[0007]
[Problems to be solved by the invention]
However, in a high-definition color cathode ray tube having an extremely small electron beam landing margin, the amount of displacement of the color selection mechanism having such a bimetal structure is not sufficient, and it is difficult to obtain an optimum mislanding correction.
That is, when the spring holder 49 of FIG. 8 has a bimetal structure, the displacement of the color selection mechanism 39 is more elastically imparted by the displacement by the bimetal structure spring holder 49 fixed to the support members 41 and 42 of the frame 45. The displacement is larger than the displacement caused by the metal member (STC plate) 54 fixed to the members 43 and 44. For this reason, the plate thickness of the spring holder 49 is reduced, or the U-shaped portion is enlarged to increase the displacement, but this is insufficient.
Also, if the plate thickness of the bimetal structure spring holder 49 is reduced, the impact resistance of the cathode ray tube is deteriorated, and if the U-shaped portion is enlarged, the processing shape is limited due to problems such as processing cracks during press forming. Therefore, at present, an optimum displacement amount cannot be obtained as the color selection mechanism 39.
Further, since the color selection mechanism 39 is displaced by the curvature of the bimetal structure spring holder 49 during thermal expansion, the fitting position between the panel pin 55 and the support spring 51 changes, which is caught by the support spring 51 and does not return. Because of the state, beam landing was also a cause of variation.
[0008]
Further, in the color selection mechanism disclosed in Japanese Patent Application Laid-Open No. H10-255677, since a metal member is fixed to the back surface of the support member to form a bimetal structure, impurities such as dust and oil may be present in the gap between the support member and the metal member. There is a risk of intrusion, and it has not reached practical use.
Further, in the color selection mechanism disclosed in Japanese Patent Application Laid-Open No. 2000-357466, a bimetal structure is formed with a different coefficient of thermal expansion between the outside and the inside of the member having the L-shaped cross section, but this bimetal structure is thermally affected. In such a case, a member having a higher thermal expansion coefficient (an outer member) thermally expands in the longitudinal direction, and there is a possibility that mislanding correction may not be sufficiently performed, so that it has not been practically used.
[0009]
The present invention has been made in view of the above points, and provides a cathode ray tube and a color selection mechanism capable of appropriately displacing a color selection mechanism toward a phosphor screen side when subjected to thermal influence so as to perform optimal mislanding correction. Is what you do.
[0010]
[Means for Solving the Problems]
In the cathode ray tube according to the present invention, a pair of support members constituting a frame are formed of a bimetallic steel material of a clad material obtained by bonding a high thermal expansion coefficient material and a low thermal expansion coefficient material, and a color is provided between the pair of support members. A configuration is provided with a color selection mechanism in which a selection electrode thin plate is stretched.
[0011]
According to the cathode ray tube of the present invention, the support member constituting the color selection mechanism is formed of a bimetallic steel material made of a clad material, and in particular, the lower surface side of the horizontal portion of the L-shaped support member is formed of a material having a high coefficient of thermal expansion. When the color selection mechanism is thermally affected during operation, the opposing support members are uniformly displaced toward the fluorescent screen side, and mislanding in the periphery is suppressed.
[0012]
In the color selection mechanism according to the present invention, the pair of support members constituting the frame are formed of a bimetallic steel material made of a clad material in which a high thermal expansion coefficient material and a low thermal expansion coefficient material are bonded, and a color is provided between the pair of support members. The configuration is such that the sorting electrode plate is stretched.
[0013]
According to the color selection mechanism of the present invention, since the support member of the frame is formed of a bimetallic steel material made of a clad material, the opposing support members are uniformly displaced toward the fluorescent screen when thermally affected. Therefore, when applied to a cathode ray tube, it is possible to suppress mislanding in the periphery.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0015]
FIG. 1 shows an embodiment of a cathode ray tube according to the present invention. In the cathode ray tube 1 according to the present embodiment, a color phosphor screen 4 made up of striped red, green and blue phosphor layers is formed on the inner surface of the panel 3 of the cathode ray tube body 2 and faces the color phosphor screen 4. Then, the color selection mechanism 5 according to the present invention is arranged, and the electron gun 6 is arranged at the neck 7 of the tube 2. Reference numeral 8 denotes a deflection yoke.
In the cathode ray tube 1, three electron beams for red, green and blue emitted from an electron gun 6 are irradiated on a color phosphor screen 4 by a color selection mechanism 5 and scanned in a horizontal and vertical direction by a deflection yoke 8. And display the required image.
[0016]
As shown in FIG. 2, the color selection mechanism 5 includes a pair of opposing support members 10 and 11 having an L-shaped cross section and a pair of support members 10 supporting between the ends of the support members 10 and 11. A frame-shaped metal frame 14 is provided, which is formed of elastic members 12 and 13 in the shape of a letter, and a large number of ribbon-shaped grid elements 15 are provided between the support members 10 and 11 of the frame 14 in the form of a large number of slits. In order to form the beam transmission holes 16, the color selection electrode thin plates 17 arranged in a direction crossing each phosphor stripe at a predetermined pitch along the horizontal direction of the screen are stretched with a predetermined tension. A metal member (STC plate) 18 having a higher coefficient of thermal expansion than the elasticity imparting members 12 and 13 is provided below the elasticity imparting members 12 and 13 in order to provide a bimetal effect between the elasticity imparting members 12 and 13. Are welded. Here, in the supporting members 10 and 11 which are bent into an L-shape and have an L-shaped cross section, a portion extending in the vertical direction is defined as a vertical portion 27V including a portion extending vertically and slightly obliquely from the vertical. The portion extending in the horizontal direction is defined as a horizontal portion 27H (see FIGS. 2 and 3).
The color selection mechanism 5 is disposed in the panel 3 of the cathode ray tube 1 so as to be opposed to the fluorescent screen 4 by three-point support or four-point support, in the illustrated example, four-point support. Therefore, a support spring 21 having an engagement hole 20 at each end is welded to each of four sides of the frame 14, that is, the support members 10 and 11 and the elasticity providing members 12 and 13 via the spring holder 19. The color selection mechanism 5 is mounted on the panel 3 by fitting the respective engagement holes 20 of the support spring 21 to panel pins 38 provided at four positions on the inner surface of the panel 3.
[0017]
In the present embodiment, the pair of support members 10 and 11 constituting the frame 14 are formed of a bimetallic steel material made of a clad material 28 in which a high thermal expansion coefficient material 25 and a low thermal expansion coefficient material 26 are bonded. That is, the color selecting electrode thin plate 17 is welded to the upper surface of the vertical portion 27V of the support members 10 and 11 having the L-shaped cross section, and the high thermal expansion coefficient material 25 is formed on the lower surface side of the horizontal portion 27H.
[0018]
As shown in FIG. 3, the support members 10 and 11 are provided with a high thermal expansion coefficient material 25 on the lower surface side in a range of a horizontal area a extending in a horizontal direction when viewed from above from an L-shaped bent state. Is formed. The thickness _{T 2} of the high thermal expansion coefficient material 25 is chosen in the thickness _T of less than ₁ at least 30% of the thickness _{T 1} of the support members 10 and 11, suitably set according to the ratio (%) is the type of cathode ray tube Is done. When the ratio of the thickness T ₂ of the high thermal expansion coefficient material 25 is less than 30% of the thickness T _1, it can not be performed sufficiently bimetal effect is small mislanding correction.
That is, as shown in FIG. 7, the bimetal ratio of the support member of the frame, i.e. mislanding amount and the _second thickness T ₂ ratio, due to thermal expansion of the frame of the high thermal expansion coefficient material 25 against the plate thickness T ₁ of the support member (relative looking at the relationship between the value), when the determined standard value for acceptable mislanding the (mislanding weight) and 25 or less, the ratio of the thickness T ₂ of the high thermal expansion coefficient material becomes 28% or more, and for safety 30% or more.
[0019]
It is preferable that the difference between the coefficients of thermal expansion of the high thermal expansion coefficient material 25 and the low thermal expansion coefficient material 26 constituting the bimetal structure is 4.0 × 10 ⁻⁶ / ° C. or more. If the difference in thermal expansion coefficient is less than 4.0 × 10 ⁻⁶ / ° C., the bimetal effect is small and mislanding correction cannot be performed sufficiently.
[0020]
The clad material 28 is formed by normal rolling. In the case of this example, the high thermal expansion material 25 and the low thermal expansion material 26 are rolled in a state where they are bonded together by welding or the like. A clad material (see FIG. 4) obtained by bonding a high thermal expansion material 25 to a part of a low thermal expansion material 26 is cut into a predetermined length, bent, and formed into an L-shaped cross section. The supporting members 10 and 11 having a bimetal structure in which a high thermal expansion coefficient material 25 is formed on the lower surface side of the horizontal portion and the other portions are formed of a low thermal expansion coefficient material 26 are formed.
[0021]
FIG. 5 shows another example of the support members 10 and 11. In this example, the end portions 25A of the high thermal expansion coefficient material 25 are formed so as to be oblique rather than vertical, so that the high thermal expansion coefficient material 25 is hardly peeled off.
[0022]
Next, the operation of mislanding correction (so-called temperature drift correction) using the bimetal structure of the present embodiment will be described.
As shown in FIG. 6, when the color selection mechanism 5 is thermally affected from a state in which the color selection mechanism 5 is not thermally affected (the state shown by the solid line), the support members 10 and 11 of the frame 14 move in the longitudinal direction. any beam transmitting hole 16 in the peripheral portion of the color selecting electrode thin plate 17 by thermal expansion is displaced to the position a ₂ from the position a _1, but the support members 10 and 11 by acting bimetallic structure of the support member itself is at the same time It is displaced to the fluorescent screen 4 side. That is, the color selecting electrode thin plate 17 is displaced a beam transmitting hole 16 to the position A ₃ on the locus of the electron beam passing through the beam transmitting hole 16 when the frame 14 is not deformed (the state of a dotted line shown). As a result, the electron beam is corrected for mislanding and is irradiated on the phosphor screen 4 at a regular position.
[0023]
According to the present embodiment, the support members 10 and 11 constituting the frame 14 of the color selection mechanism 5 are formed of a clad material in which a high thermal expansion coefficient material 25 and a low thermal expansion coefficient material 26 are previously bonded together. 28 and a bimetal structure over the entire length of the support members 10 and 11 so as to have the high thermal expansion material 25 on the lower surface side of the horizontal portion 27H having an L-shaped cross section composed of the vertical portion 27V and the horizontal portion 27H. Accordingly, when the color selection mechanism 5 is thermally affected during the operation of the cathode ray tube 1, the displacement of the color selection mechanism 5 toward the fluorescent screen 3 can be increased, and the mislanding at the peripheral portion of the screen, particularly, at the periphery can be reduced. be able to.
[0024]
By selecting the bimetal structure ratio of the supporting members 10 and 11, that is, the ratio of the thickness of the low thermal expansion coefficient material 26 to the high thermal expansion coefficient material 25, and the coefficient of thermal expansion, the optimal degree of freedom from small tubes to large tubes is high. The displacement amount can be designed.
Since the color selecting mechanism is not displaced by the bending of the bimetallic spring holder, the support spring 21 is not caught on the panel pin 38, and the beam landing varies, thereby producing a color cathode ray tube with stable quality. it can.
Since the pair of support members 10 and 11 are formed of a bimetallic steel material made of a clad material, unlike the case of welding or the like, no impurities such as dust and oil enter the bimetal structure.
[0025]
In the present invention, the above-described color cathode ray tube 1 is incorporated into a set, and can be configured as a display device such as a receiver, a monitor, and a display.
[0026]
【The invention's effect】
According to the color selection mechanism of the present invention, the bimetal structure of the support member that constitutes the frame makes it possible to increase the amount of displacement of the color selection mechanism toward the fluorescent screen when thermally affected. In addition, mislanding, particularly in the peripheral portion of the screen, can be properly corrected. By selecting the bimetal structure ratio and the coefficient of thermal expansion of the support member, it is possible to design an optimal displacement with a high degree of freedom from small tubes to large tubes. Since the spring is not displaced by the distortion of the spring holder having the bimetal structure, the support spring is not caught on the panel pin. Variations in beam landing can be reduced. Since the support member is formed of the clad material, impurities such as dust and oil do not enter the bimetal structure of the support member.
[0027]
According to the cathode ray tube according to the present invention, by providing the above-described color selection mechanism, a cathode ray tube having stable quality can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing one embodiment of a cathode ray tube according to the present invention.
FIG. 2 is a schematic configuration diagram illustrating an embodiment of a color selection mechanism according to the present invention.
FIG. 3 is an enlarged cross-sectional view illustrating a main part of a support member of the color selection mechanism.
FIG. 4 is an explanatory diagram of a clad material.
FIG. 5 is an enlarged sectional view showing another example of a support member of the color selection mechanism.
FIG. 6 is an explanatory diagram showing an operation when the color selection mechanism of the present invention thermally expands.
FIG. 7 is a graph showing a relationship between a ratio of a material having a high thermal expansion coefficient to a plate thickness of a support member having a bimetal structure of a color selection mechanism according to the present invention and an amount of mislanding.
FIG. 8 is a schematic configuration diagram of a conventional color selection mechanism.
FIG. 9 is an explanatory diagram of a mislanding.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cathode ray tube, 2 ... Cathode ray tube body, 3 ... Panel, 4 ... Phosphor screen, 5 ... Color selection electrode, 6 ... Electron gun, 10, 11 ... Support Member, 12, 13: Elasticity imparting member, 14: Frame, 15: Grid element, 16: Beam transmitting hole, 17: Electrode thin plate for color selection, 18: Metal member (STC), 19: spring holder, 20: engagement hole, 21: support spring, 25: high thermal expansion material, 26: low thermal expansion material, 27V: vertical portion , 27H ... horizontal part

Claims (8)

A pair of support members constituting the frame are formed of a bimetallic steel material of a clad material obtained by bonding a high thermal expansion material and a low thermal expansion material, and a color selection electrode thin plate is stretched between the pair of support members. A cathode ray tube comprising a color selection mechanism comprising: A pair of support members of the frame are formed in an L-shaped cross section;
The electrode plate for color selection is joined to the upper surface of the vertical portion having the L-shaped cross section,
2. The cathode ray tube according to claim 1, wherein the lower surface of the horizontal portion having the L-shaped cross section is formed of the high thermal expansion material. The cathode ray tube according to claim 2, wherein the thickness of the high thermal expansion material is 30% or more of the plate thickness of the support member and less than the plate thickness. The cathode ray tube according to claim 1, wherein a difference in thermal expansion coefficient between the high thermal expansion material and the low thermal expansion material is 4.0 × 10 ⁻⁶ / ° C. or more. A pair of support members constituting the frame are formed of a bimetallic steel material of a clad material obtained by bonding a high thermal expansion coefficient material and a low thermal expansion coefficient material,
A color selection mechanism, wherein a color selection electrode thin plate is stretched between the pair of support members. A pair of support members of the frame are formed in an L-shaped cross section;
The electrode plate for color selection is joined to the upper surface of the vertical portion having the L-shaped cross section,
6. The color selection mechanism according to claim 5, wherein a lower surface of the horizontal portion having the L-shaped cross section is formed of the high thermal expansion material. 7. The color selection mechanism according to claim 6, wherein the thickness of the high thermal expansion material is 30% or more and less than the plate thickness of the support member. 6. The color selection mechanism according to claim 5, wherein a difference in thermal expansion coefficient between the high thermal expansion coefficient material and the low thermal expansion coefficient material is 4.0 × 10 ⁻⁶ / ° C. or more.

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