JPH0729502A - Internal beam shielding plate for cathode-ray tube and color selecting mechanism assembly body - Google Patents

Abstract

PURPOSE:To provide an internal beam shielding plate by which temperature drift in a cathode-ray tube is compensated optimally. CONSTITUTION:An internal beam shielding plate 30 for a cathode-ray tube is composed of an internal beam shielding plate body 32 and an internal beam shielding plate installing part 34 extending from the internal beam shielding plate body 32. The sum total (L1+L2) of lengths of boundaries 36 between this internal beam shielding plate installing part 34 and the internal beam shielding plate body 32 is set in 2 to 20% of a length (L0) of the internal beam shielding plate body 32.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to an internal beam shield and color selection mechanism assembly for a cathode ray tube.

[0002]

2. Description of the Related Art As shown in FIG. 6A, a color selection mechanism assembly in a Trinitron (registered trademark) type cathode ray tube has a color selection mechanism 10 including an aperture grill and a color selection mechanism 10 formed by a seam welding method. A pair of first frame members 12 attached to each other, a pair of second frame members 14 welded to respective ends of the first frame members 12 to support the pair of first frame members 12, Self-temperature correction plate (STC plate) 20 attached to each top surface 14B of the second frame member 14, and self-temperature correction plate 2
It consists of an inner beam shield plate 30A welded on top of 0.
A support member (not shown) for fixing the color selection mechanism assembly to a panel (not shown) is attached to the side surfaces of the first frame member 12 and the second frame member 14.
Further, an internal magnetic shield plate (not shown) is attached to prevent color shift due to the influence of external magnetism.

The internal beam shield plate 30A is provided for the purpose of preventing diffused reflection of an overscanned electron beam. When the internal beam shield plate 30A is not provided,
Under the influence of the irregularly reflected electron beam, there are problems that a shadow is generated on the screen of the cathode ray tube and that the screen is dimly illuminated.

The electron beam emitted from the electron gun is scanned by the deflection yoke and is applied to the color selection mechanism assembly. As a result, the temperature of the color selection mechanism 10 rises due to the energy of the electron beam, and the first frame member 12 passes through the welded portion of the color selection mechanism 10 and the first frame member 12.
Heat is transmitted to. Therefore, the temperature of the first frame member 12 rises, and the first frame member 12 expands and is displaced in the longitudinal direction (the direction of arrow A in FIG. 6A). At this time, the second frame member 14 welded to the first frame member 12 also rises in temperature and is displaced outward (in the direction of arrow B in FIG. 6A) in accordance with the displacement of the first frame member 12.

As shown in FIG. 7A, for example, the first
Before the frame member 12 is displaced, it is assumed that the slit 10A of the color selection mechanism 10 and the photoconductor stripe 40 corresponding to this slit 10A have a correct positional relationship. still,
Photoreceptor stripe 40 having such a correct positional relationship
Is shown in black. The photoconductor stripe 40 is formed on the panel 42. However, as shown in FIG. 7B, when the first frame member 12 is displaced by the direction and distance indicated by the arrow C, the slit 10A of the color selection mechanism 10 is moved.
And the photoconductor stripe 4 corresponding to this slit 10A.
0 deviates from the correct positional relationship. As a result, so-called mislanding occurs and color misregistration occurs. In addition, in order to show the position of the slit 10A before the displacement in FIG. 7B, one slit is shown by a broken line.

The mislanding caused by the displacement of the first and second frame members 12, 14 due to such thermal expansion is called temperature drift. Conventionally, in order to compensate for this temperature drift, the self-temperature correction plate 20 is
A mechanism for self-compensating for temperature drift is adopted by welding to the frame member 14. Specifically, the self-temperature correction plate 20 includes the first frame member 12 of the second frame member 14.
Is attached to the top surface 14B opposite to the surface on which the second frame member 14 and the self-temperature correction plate 2 are attached.
A bimetal is formed with 0. The self-temperature correction plate 20 is
The second frame member 14 is made of a material having a larger thermal expansion coefficient than that of the material (for example, low carbon steel), such as stainless steel or iron-nickel alloy.

The cathode ray tube operates to operate the second frame member 14
When the temperature rises, the temperature of the self-temperature correction plate 20 also rises. Since the coefficient of thermal expansion of the material forming the self-temperature correction plate 20 is larger than the coefficient of thermal expansion of the material forming the second frame member 14, the second frame member 14 is schematically illustrated in FIG. 8B. As it does, it bends inward and deforms. Hereinafter, such an effect is referred to as a bimetal effect. The state before the operation of the cathode ray tube is shown in FIG. As a result, as shown in FIG. 8B, the color selection mechanism 10 (shown by the dotted line) before the cathode ray tube operates is
It is pushed out to the panel 42 side together with the frame member 12.
Therefore, as shown in FIG. 7C, the color selection mechanism 10 is pushed toward the panel 42 by the direction and distance indicated by the arrow D. In addition, in FIG. 7C, one slit is shown by a broken line in order to show the position of the slit 10A in the state of FIG. 7B. As a result, the slit 1 of the color selection mechanism 10
The positional relationship between 0A and the photoconductor stripe 40 corresponding to the slit 10A is restored to the correct positional relationship, and mislanding (temperature drift) is eliminated.

[0008]

As described above, the heat generated by expanding the first frame member 12 is generated by the second frame member 14.
By being transmitted to the self-temperature correction plate 20, the bimetal effect is generated and the mislanding is eliminated.
However, in the conventional color selection mechanism assembly, the internal beam shield plate 30A is welded to the self-temperature correction plate 20. A perspective view of a conventional internal beam shield plate 30A is shown in FIG. 6 (B). The internal beam shield plate 30A includes an internal beam shield plate body 32A and an internal beam shield plate mounting portion 34A extending from the internal beam shield plate body 32A. In the conventional internal beam shield plate 30A, the total length (L = L1 + L2 +) of the boundary line 36A (indicated by a dotted line) between the internal beam shield plate mounting portion 34A and the internal beam shield plate body 32A.
L3) is 25% or more of the length (L0) of the internal beam shield main body 32A. In addition, in FIG. 6B, the boundary line 3
6A is shown by a dotted line. In addition, the internal beam shield plate body 3
The length (L0) of 2A is the boundary line 36A and its extension line 36.
It is the length of the inner beam shield body along A.

Meanwhile, the internal beam shield plate 30A also rises in temperature upon being irradiated with the electron beam. As a result, the temperature of the self-temperature correction plate 20 rises due to the heat from the internal beam shield plate 30A, the bimetal effect of the self-temperature correction plate 20 appears strongly immediately after the operation of the cathode ray tube, and the temperature drift is overcompensated. Therefore, a large mislanding occurs in a direction opposite to the moving direction of the electron beam on the panel 42, which is generated by the thermal expansion of the first and second frame members 12 and 14.

That is, when the cathode ray tube starts to operate, first, the electron beam on the panel 42 has a certain direction (this direction is a positive direction, and the opposite direction is a negative direction). ) To start moving. After that, the temperature rise of the internal beam shield plate 30A due to the irradiation of the electron beam causes an excessive bimetal effect of the self-temperature correction plate 20, and the color selection mechanism 10 is excessively pushed to the panel 42 side. As a result, the electron beam on the panel 42 moves in the negative direction.

Then, after a certain time elapses, the temperature of the color selection mechanism 10 rises due to the irradiation of the electron beam, so that the first and second frame members 12 and 14 thermally expand, and the color selection mechanism 10 and the panel 42 are separated from each other. It is pushed back in the opposite direction. As a result, the electron beam on the panel 42 moves in the positive direction. Then, after a certain time elapses, the color selection mechanism assembly comes into thermal equilibrium and the electron beam reaches a certain position on the panel 42.

Further, when a thin member is used for the second frame member 14, the bimetal effect becomes too sensitive and a slight heat causes the bimetal effect, and the negative direction of the electron beam on the panel 42 is generated. To move to.

Therefore, it is a first object of the present invention to provide an internal beam shield plate capable of optimally compensating for temperature drift in a cathode ray tube. Further, a second object of the present invention is to provide a color selection mechanism assembly capable of optimally compensating for temperature drift.

[0014]

A first object of the present invention is to provide an internal beam shield plate for a cathode ray tube comprising an internal beam shield plate body and an internal beam shield plate mounting portion extending from the internal beam shield plate body. For the cathode ray tube of the present invention, the sum of the lengths of the boundary lines between the inner beam shield mounting portion and the inner beam shield body is 2 to 20% of the length of the inner beam shield body. This can be achieved by an internal beam shield.

In the color selection mechanism assembly of the present invention, the opening can be formed on the boundary line between the internal beam shield mounting portion and the internal beam shield main body. The length of the internal beam shield plate body is the length of the internal beam shield plate body along the boundary line and its extension. When the opening is formed on the boundary, the total length of the boundary does not include the length of the opening.

The above-mentioned second object is to provide a color selection mechanism, a set of first frame members to which the color selection mechanism is attached, a set of second frame members for supporting the set of first frame members, A color selection mechanism assembly comprising a self-temperature compensating plate and an internal beam shield plate attached to each of the second frame members, wherein the internal beam shield plate is directly attached to the respective second frame members. Can be achieved by the color selection mechanism assembly of the present invention.

In the color selection mechanism assembly of the present invention, each internal beam shield plate may be attached to each of the opposing surfaces of the second frame member. Alternatively, each inner beam shield may be attached to a respective surface of the second frame member opposite the opposite surface. Furthermore, each internal beam shield plate,
It can be attached to each surface of the second frame member to which the self-temperature correction plate is attached and outside the self-temperature correction plate.

[0018]

In the internal beam shield plate of the present invention, the total length of the boundary lines between the internal beam shield plate mounting portion and the internal beam shield plate body is 2 to 2 of the length of the internal beam shield plate body.
It is 0%. The internal beam shield plate is heated by the irradiation of the electron beam. However, by thus defining the total length of the boundary line between the internal beam shield mounting portion and the internal beam shield main body, the amount of heat transferred to the self-temperature correction plate can be made smaller than that of the conventional internal beam shield. Can be reduced. Therefore, the bimetal effect of the self-temperature correction plate can be suppressed, and the temperature drift can be optimally compensated.

Further, in the color selecting mechanism assembly of the present invention, since the internal beam shield plate is directly attached to the second frame member, it is possible to prevent heat from the internal beam shield plate from being directly transferred to the self-temperature correction plate. It is possible to prevent it, suppress the bimetal effect of the self-temperature correction plate, and optimally compensate the temperature drift.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings.

First, the internal beam shield plate of the present invention will be described below. FIG. 1A is a perspective view of a color selection mechanism assembly to which the internal beam shield plate of the present invention is attached. Further, FIG. 1B shows a perspective view of the internal beam shield plate of the present invention.

The color selection mechanism assembly in the Trinitron (registered trademark) type cathode ray tube has the same structure as that shown in FIG. 6 except that the structure of the internal beam shield plate 30 is different. That is, a color selection mechanism 10 including an aperture grill, a set of first frame members 12 to which the color selection mechanism 10 is attached by a seam welding method, and a first frame member for supporting a set of first frame members 12. A pair of second frame members 14 welded to each end of 12,
A self-temperature correction plate (STC plate) 20 attached to each of the second frame members 14, and an internal beam shield plate 3
It consists of zero. A support member (not shown) for fixing the color selection mechanism assembly to a panel (not shown) is attached to the side surfaces of the first frame member 12 and the second frame member 14. Further, an internal magnetic shield plate (not shown) is attached to prevent color shift due to the influence of external magnetism.

The internal beam shield plate 30 is provided for the purpose of preventing irregular reflection of the overscanned electron beam. As shown in FIG. 1B, the internal beam shield plate 30 includes an internal beam shield plate body 32 and an internal beam shield plate mounting portion 34 extending from the internal beam shield plate body 32.
Consists of. The inner beam shield plate main body 32 and the inner beam shield plate mounting portion 34 are integrated.

A total length L of a boundary line 36 (shown by a dotted line) between the inner beam shield mounting portion and the inner beam shield body.
(For example, in the example shown in FIG. 1B, L = L1 + L
2) is 2 to 2 of the length (L0) of the inner beam shield plate body.
It is 0%. The inner beam shield mounting portion 34 is welded onto the self-temperature correction plate 20. That is, the internal beam shield plate 30 is in contact with the self-temperature correction plate 20 at the internal beam shield plate mounting portion 34. If the total length L of the boundary line 36 between the internal beam shield plate mounting portion and the internal beam shield plate body is less than 2% of the length (L0) of the internal beam shield plate body,
It becomes difficult to attach the internal beam shield plate 30 to the color selection mechanism assembly, or the attachment strength decreases.
Further, if it exceeds 20%, the amount of heat transferred from the internal beam shield plate 30 to the self-temperature correction plate 20 becomes too large.

Upon receiving the electron beam irradiation, the temperature of the internal beam shield plate 30 of the present invention rises. However,
Internal beam shield plate mounting portion 34 and internal beam shield plate body 3
By defining the total length (L) of the boundary line 36 with respect to 2, the amount of heat transfer to the self-temperature correction plate 20 can be reduced, and the bimetal effect of the self-temperature correction plate 20 can be suppressed. . Therefore, the temperature drift can be optimally compensated.

A color selection mechanism assembly including the internal beam shield plate 30 of the present invention and the conventional internal beam shield plate 30A (see FIG. 6B) until 180 minutes have elapsed from the start of operation of the cathode ray tube. FIG. 2 shows the displacement of the electron beam on the panel 42 at. The internal beam shield plate 30 of the present invention
In the above, the value of L / L0 was set to 0.033. Also,
In the conventional internal beam shield plate 30A, the value of L / L0 is 0.27.

In the conventional color selection mechanism assembly including the internal beam shield plate 30A, as shown by the broken line in FIG.
The panel 42 is operated for 5 to 20 minutes after the start of operation of the cathode ray tube.
The upper electron beam is moving in the negative direction. this is,
As described above, as a result of the energy being given from the electron beam and the temperature of the internal beam shielding plate 30A rising, the bimetal effect of the self-temperature correction plate 20 strongly appears,
This is because the temperature drift is excessively compensated.

On the other hand, in the color selection mechanism assembly having the internal beam shield plate 30 of the present invention, as shown by the solid line in FIG.
The upper electron beam is moving almost monotonically in the positive direction. As described above, this is because the temperature of the internal beam shield plate 30 rises due to the energy provided from the electron beam, but the boundary line 36 between the internal beam shield plate mounting portion 34 and the internal beam shield plate body 32. Since the total length (L) of the self-temperature compensation plate 20 is defined, the amount of heat transferred from the internal beam shield plate 30 to the self-temperature compensation plate 20 can be reduced, and the bimetal effect of the self-temperature compensation plate 20 can be suppressed. Is.
Further, when the internal beam shield plate 30 of the present invention is used, the cathode ray tube reaches a stable operating state earlier.

As described above, the internal beam shield plate 3 of the present invention is used.
It can be seen from FIG. 2 that the temperature drift is optimally compensated for in a cathode ray tube with zero.

The internal beam shield plate 30 of the present invention, the perspective view of which is shown in FIG. 3, is a modification of the internal beam shield plate 30 shown in FIG. In this internal beam shield plate 30, an opening 38 is formed on a boundary line 36 (indicated by a dotted line) between the internal beam shield plate mounting portion 34 and the internal beam shield plate body 32. By providing such an opening 38,
Internal beam shield plate mounting portion 34 and internal beam shield plate body 3
The total length (L) of the boundary line 36 with 2 is regulated to 2 to 20% of the length (L0) of the main body 32 of the internal beam shield plate, and the transmission from the internal beam shield plate 30 to the self-temperature correction plate 20 is controlled. At the same time as controlling the amount of heat, the mounting area of the internal beam shield plate mounting portion 34 to the self-temperature correction plate 20 can be increased, and the internal beam shield plate 30 can be mounted to the self-temperature correction plate 20 more reliably. Become.

Next, the color selection mechanism assembly of the present invention will be described. The color selection mechanism assembly of the present invention includes an internal beam shield plate 3.
The structure is similar to that of the color selecting mechanism assembly shown in FIG. 1 except for the structure of 0 and the mounting position, and thus detailed description thereof will be omitted.

As shown in the perspective view of FIG. 4A, in the color selection mechanism assembly of the present invention, the internal beam shield plate 3 is used.
0 is directly attached to each of the second frame members 14. Unlike the color selection mechanism assembly shown in FIG.
The internal beam shield plate 30 is not in direct contact with the self-temperature correction plate 20. More specifically, the internal beam shield plate 30
Are opposite surfaces 14 of the second frame member 14.
It is attached to A. Internal beam shield plate 30 and second
In order to clarify the mounting relationship with the frame member 14, FIG. 4B shows a layout view of the second frame member 14 as viewed in the longitudinal direction.

FIG. 5A shows another embodiment of the internal beam shield plate 30 in the color selection mechanism assembly of the present invention.
The internal beam shield plate 30 is attached to each surface 14C of the second frame member 14 on the side opposite to the facing surface 14A. In order to clarify the mounting relationship between the internal beam shield plate 30 and the second frame member 14, FIG. 5A shows a layout view of the second frame member 14 as viewed in the longitudinal direction.

FIG. 5B shows an internal beam shield plate 30 of still another mode in the color selection mechanism assembly of the present invention. The internal beam shield plate 30 is a self-temperature correction plate 20.
To the surface 14B of the second frame member 14 to which is attached,
Further, it is attached to the outside of the self-temperature correction plate 20.

Although the internal beam shielding plate for the cathode ray tube and the color selecting mechanism assembly of the present invention have been described based on the embodiments, the present invention is not limited to these embodiments. The shapes and structures of the internal beam shield plate and the color selection mechanism assembly described in the embodiments are examples and can be changed as appropriate. Further, the materials for producing the elements constituting the color selection mechanism assembly are also examples, and can be appropriately selected according to the required characteristics and the like.

[0036]

According to the present invention, the amount of heat transferred from the internal beam shielding plate to the self-temperature correction plate is controlled, and thus the bimetal effect of the self-temperature correction plate can be suppressed and the temperature drift compensation is optimized. It becomes possible to do it. Further, it is possible to shorten the time until the displacement of the electron beam with respect to the panel reaches equilibrium in a shorter time than before and the operation of the cathode ray tube becomes stable.

[Brief description of drawings]

FIG. 1 is a perspective view of an internal beam shield plate of the present invention and a color selection mechanism assembly to which the internal beam shield plate is applied.

FIG. 2 is a diagram showing displacement of an electron beam on a panel in a color selection mechanism assembly including an internal beam shield plate of the present invention and a conventional internal beam shield plate.

FIG. 3 is a perspective view showing an internal beam shield plate according to another embodiment of the present invention, which is different from FIG.

FIG. 4 is a perspective view of a color selection mechanism assembly of the present invention, and a view for explaining attachment of an internal beam shield plate to the color selection mechanism assembly.

FIG. 5 is a view for explaining another form of the internal beam shield plate for the color selection mechanism assembly of the present invention.

FIG. 6 is a perspective view of a conventional color selection mechanism assembly.

FIG. 7 is a diagram schematically showing a positional relationship between a slit of a color selection mechanism and a photoconductor stripe corresponding to the slit.

FIG. 8 is a schematic diagram for explaining a bimetal effect of a self-temperature correction plate.

[Explanation of symbols]

 10 Color Selection Mechanism 10A Slit 12 First Frame Member 14 Second Frame Member 14A, 14B, 14C Surface of Second Frame Member 20 Self-Temperature Correction Plate 30 Internal Beam Shield Plate 32 Internal Beam Shield Plate Body 34 Internal Beam Shield Plate Attachment Section 36 boundary line 38 opening 40 photoconductor stripe 42 panel

Claims (6)

[Claims] 1. An internal beam shield plate for a cathode ray tube comprising an internal beam shield plate body and an internal beam shield plate mounting portion extending from the internal beam shield plate body, the internal beam shield plate mounting portion and the internal beam shield plate. The internal beam shield for a cathode ray tube, wherein the total length of the boundary line with the main body is 2 to 20% of the length of the main body of the internal beam shield. 2. The internal beam shield plate for a cathode ray tube according to claim 1, wherein an opening is formed on a boundary line between the internal beam shield plate mounting portion and the internal beam shield plate body. 3. A color selection mechanism, a set of first frame members to which the color selection mechanism is attached, a set of second frame members supporting the set of first frame members, and a second frame member. A color selection mechanism assembly comprising a self-temperature correction plate and an internal beam shield plate attached to each of them, wherein the internal beam shield plate is directly attached to each second frame member. Assembly. 4. The color selection mechanism assembly according to claim 3, wherein each of the internal beam shield plates is attached to each of the opposing surfaces of the second frame member. 5. The color selection mechanism assembly according to claim 3, wherein each of the internal beam shielding plates is attached to each surface of the second frame member opposite to the facing surface thereof. . 6. The internal beam shield plate is attached to each surface of the second frame member to which the self-temperature compensating plate is attached and outside the self-temperature compensating plate. The color selection mechanism assembly according to item 3.