JPH11176355A - Cathode-ray tube device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure sufficient atmospheric pressure resistance of a vacuum envelope, if a yoke is formed into a pyramid shape, effectively reduce deflecting electric power and meet requirement for higher brightness and higher frequency deflection. SOLUTION: In a cathode-ray tube device, for which a neck with an electron gun inside and a glass vacuum envelope mounted with a deflection yoke and provided with a yoke 14 connected to the fluorescent screen side of the neck are formed at the rear part of a panel with a fluorescent screen inside, the yoke 14 in a sectionally noncircular pyramid shape has a length from the connection position of the neck to the end on the screen side of the deflection yoke. If an space between the tubular axis and the inner wall of the yoke and a space between the tubular axis and the outer wall of the yoke are the inner diameter and the outer diameter of the yoke in a vertical plane against the tubular axis, at least one vertical section against the tubular axis has the maximum outer diameter of the yoke in a direction D0 between the direction V of a vertical axis and the direction H of a horizontal axis of a screen and shows θi ≠θ0 where an angle between the horizontal axis and a direction Di formed by the maximum inner diameter of the yoke is θi and an angle between the horizontal axis and a direction D0 formed by the maximum outer diameter of the yoke is θ0 .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube device such as a color cathode ray tube, and more particularly to a cathode ray tube device capable of effectively reducing deflection power and securing the pressure resistance of a vacuum envelope.

[0002]

2. Description of the Related Art A color picture tube is an example of a cathode ray tube.
The display has a glass vacuum envelope consisting of a substantially rectangular panel, a funnel-shaped funnel connected to the panel, and a cylindrical neck connected to the funnel.

Further, a deflection yoke is mounted from the neck side to the funnel side, and the funnel has a small diameter portion from a connection portion with the neck to a position where the deflection yoke is mounted, a so-called yoke portion. .

On the inner surface of the panel, there is provided a phosphor screen composed of a three-color phosphor layer in the form of dots or stripes that emit blue, green, and red light. The shadow mask in which the electron beam passage holes are formed is disposed. An electron gun for emitting three electron beams is provided in the neck, and the electron beam is horizontally and vertically deflected by a horizontal and vertical deflection magnetic field generated by the deflection yoke. By scanning the screen horizontally and vertically,
It is formed in a structure for displaying a color image.

In such a picture tube, the electron gun is of an in-line type which emits three electron beams arranged in a line passing on the same horizontal plane.
By deflecting the electron beam with these horizontal and vertical deflection magnetic fields, with the horizontal deflection magnetic field generated by the deflection yoke as a pincushion type and the vertical deflection magnetic field as a barrel type, no special correction means is required, and the entire screen is displayed. Self-convergence for concentrating three electron beams in a row
In-line type color picture tubes are widely used.

[0006] In such a cathode ray tube, the deflection yoke is a large power consumption source, and it is important to reduce the power consumption of the deflection yoke in reducing the power consumption of the cathode ray tube. That is, in order to increase the screen brightness, it is necessary to increase the cathode voltage for finally accelerating the electron beam. HD (High Definition)
In order to support OA equipment such as a TV and a PC (Personal Computer), the deflection frequency must be increased, but all of them cause an increase in deflection power.

On the other hand, regarding OA devices such as PCs in which an operator approaches the cathode ray tube and responds, regulations on leakage magnetic fields leaking from the deflection yoke to the outside of the cathode ray tube have been strengthened. As a means for reducing the magnetic field leaking from the deflection yoke to the outside of the cathode ray tube, a method of adding a compensation coil has conventionally been generally used. However, when the compensation coil is added in this manner, the power consumption of the PC increases accordingly.

In general, in order to reduce the deflection power and the leakage magnetic field, the diameter of the neck of the cathode ray tube is reduced, the outer diameter of the yoke portion on which the deflection yoke is mounted is reduced, and the operating space of the deflection magnetic field is reduced. It is preferable that the deflecting magnetic field acts efficiently on.

However, in the conventional cathode ray tube, since the electron beam passes close to the inner wall of the yoke on which the deflection yoke is mounted, the diameter of the neck 104 and the outer diameter of the yoke 110 are reduced as shown in FIG. When the electron beam 107 is further reduced, the electron beam 107 going to the diagonal portion of the phosphor screen 105 having the maximum deflection angle collides with the inner wall of the yoke portion 110, and as shown in FIG.
7, a non-colliding portion 111 is formed.

Therefore, in the conventional cathode ray tube, it is difficult to reduce the deflection power by reducing the diameter of the net or the outer diameter of the yoke portion 110. Further, if the electron beam 107 keeps colliding with the inner wall of the yoke part 110, the temperature of that part increases as the glass melts, and there is a risk of implosion.

As means for solving such a problem, Japanese Patent Publication No. 48-34349 (US Pat. No. 3,731,12)
FIG. 9A shows that, when a rectangular raster is drawn on the phosphor screen, the electron beam passage area inside the yoke portion on which the deflection yoke is mounted is also substantially rectangular. Regarding the cathode ray tube 113,
As shown in (b) to (f) in the section from B to FF, the yoke portion 110 of the funnel 103 to which the deflection yoke is mounted is gradually changed from a circular shape toward the panel 102 from the neck 104 side to a substantially rectangular shape. A varying shape is shown.

When the yoke portion 110 on which the deflection yoke is mounted is formed in a pyramid shape, the diameter of the deflection yoke in the major axis (horizontal axis: H axis) and short axis (vertical axis: V axis) directions can be reduced. Therefore, it is possible to bring the horizontal and vertical deflection coils of the deflection yoke closer to the electron beam, deflect efficiently and reduce deflection power. However, in such a cathode ray tube, in order to effectively reduce the deflection power, the closer the yoke is to a rectangular shape, the lower the pressure resistance of the vacuum envelope due to the distortion of the glass caused by the flattening, which impairs safety. It is.

At present, the flatness of the panel is indispensable because the reflection of external light and the visibility of images are strongly demanded. However, when the panel surface of the cathode ray tube is flattened, a vacuum is generated. Since the strength is deteriorated, even if a conventional funnel having a yoke portion having a pyramid shape is used as it is, a valve strength necessary for safety cannot be secured. Conventionally, for this reason, there has been a problem that the yoke portion cannot be made rectangular enough to sufficiently reduce the deflection power, or the atmospheric pressure intensity is so weak that it cannot be applied to a flat panel.

Here, regarding the above-mentioned technology for forming the yoke portion into a pyramidal shape, the applicant of the present invention circumvented the 1970's, with a deflection angle of 110 degrees / neck diameter of 36.5 mm and panel diagonal diameters of 18 ", 20", 2
2 ", 26", deflection angle 110 degrees / neck diameter 29.1 mm
And mass-produced two series, 16 "and 20". At that time, the outer surface of the panel was almost spherical and the radius of curvature of the outer surface of the panel was
This was applied to what is referred to as a 1R tube which is about 1.7 times the screen effective diameter. However, for a cathode ray tube having a panel outer surface shape twice or more the screen effective diameter, the relationship with the yoke shape was unclear due to the relationship with the bulb strength.

[0015]

As described above, in recent years, it has been required to reduce the deflection power and leakage magnetic field of a cathode ray tube. It is extremely difficult to perform the process while satisfying the high frequency. Conventionally, as a structure for reducing the deflection power, a configuration in which a pyramid-shaped yoke portion that gradually changes from a circular shape to a substantially rectangular shape in a panel direction from the neck side on a yoke portion to which the deflection yoke is mounted has been proposed. However, conventionally, it has been difficult to manufacture a vacuum envelope that achieves both sufficient atmospheric pressure strength and sufficient deflection power reduction.
The present invention has been made to solve the above-mentioned problems, and even if the yoke portion is formed into a pyramid, the pressure resistance of the vacuum envelope can be sufficiently secured, and the deflection power is effectively reduced. It is another object of the present invention to configure a cathode ray tube device which satisfies the requirements of high luminance and high frequency deflection.

[0016]

SUMMARY OF THE INVENTION A panel having at least a phosphor screen on its inner surface, a neck having an electron gun disposed on its inner surface facing the screen, and a screen connected to the neck. A glass vacuum envelope comprising a yoke portion, and an electron beam emitted from the electron gun, which is disposed on an outer surface of the vacuum envelope from the yoke portion to the neck portion, is deflected and scanned to a substantially rectangular screen area. In a cathode ray tube device comprising a deflection yoke, the yoke portion extends from a connection position of the neck portion to at least a screen side end of the deflection yoke. When the interval is the inner diameter of the yoke portion and the interval between the pipe shaft and the outer wall of the yoke portion is the outer diameter of the yoke portion, the distance between the yoke portion and the neck portion is small. At least one section perpendicular to the tube axis up to the screen side end of the deflection yoke has a non-circular shape having a maximum yoke outer diameter between the vertical axis direction and the horizontal axis direction of the screen. At least one of the non-circular cross-sections is θi ≠ θo, where θi is the angle between the horizontal axis and the inner diameter of the maximum yoke, and θo is the angle between the horizontal axis and the outer diameter of the maximum yoke. The shape of the yoke was configured as described above.

In this case, in the cross section perpendicular to the tube axis of the yoke portion, the inner wall of the yoke portion having the largest inner diameter of the yoke portion out of the space between the arbitrary inner wall of the non-circular cross section and the outer wall of the yoke portion. The shape of the yoke portion was configured so that the distance between the upper point and the point on the outer wall of the yoke portion where the outer shape of the yoke portion was maximum was not minimized.

[0018]

FIG. 3 shows the outer shape of the yoke section in a section perpendicular to the tube axis. In this non-circular cross-section, the distance from the tube axis to the outer wall of the yoke portion on the horizontal axis, vertical axis, and diagonal axis of the screen is LA. SA, DA
Then, LA and SA are smaller than DA in the pyramid-shaped yoke portion. As a result, the deflection coils near the horizontal and vertical axes can be brought closer to the electron beam to reduce the deflection power. Here, the diagonal axis distance DA having the maximum diameter is in the diagonal axis direction of the screen, but may not exactly match.

Shapes other than the three axes described above include an arc having a center on the horizontal axis and a radius Rh and a center having a center on the vertical axis and a radius Rv.
And a shape centered near the diagonal axis and connected by an arc of radius Rd. In addition, a substantially rectangular cross section can be formed using various mathematical expressions.

As described above, the deflection power can be reduced as the cross-sectional shape of the yoke portion approaches the rectangular shape, but the strength required for safety as a vacuum envelope cannot be maintained. This is shown in FIG.
As shown in FIG. 3, the flat yoke portion near the horizontal axis 115 and the vertical axis near the flat axis 115 due to the atmospheric pressure load F are indicated by broken lines 11 in FIG.
7, the compressive stresses .sigma.ho and .sigma.vo are generated on the outer walls of the yoke horizontal and vertical axes. Since a large tensile stress .sigma.do is generated on the outer wall near the yoke diagonal shaft 118, the vicinity of the yoke diagonal shaft 118 becomes a starting point, cracks are formed, and implosion occurs immediately.

The shape of the conventional pyramid-shaped yoke portion 114 is such that, when viewed in a cross section perpendicular to the tube axis, as shown in FIG.
di and the position forming the corner of the yoke outer wall, that is, the maximum yoke outer diameter position Pdo are both straight lines 1 centered on the pipe axis position O.
22, ie on the diagonal axis D. In other words, since the diagonal axes that take the maximum inner and outer diameters of the yoke are the same in the past, it is necessary to minimize the glass thickness of the diagonal where the stress is most concentrated in order to reduce the deflection power without causing neck shadow. was there. Conventionally, the strength near the diagonal axis of the yoke portion is weak and the stress concentration is large, so that the outer wall near the straight line 122 is easily cracked and imploded. Here, a region surrounded by a broken line 126 indicates a space through which the electron beam passes.

Therefore, according to the present invention, as shown in FIG. 6, the maximum yoke outer diameter position relative to the diagonal axis (Di) 122 having the maximum yoke inner diameter position Pdi of the yoke portion 14 having a substantially rectangular (non-circular) cross section. Pdo 'is shifted from the straight line 122 to the vertical axis and provided on the maximum yoke outer direction (Do) 123. In this case, the stress is maximum at σdo ', but Pdo'
Since the thickness of the portion is thicker than before, the stress is reduced. In the figure, σv'o, σd'o, σ
h′o corresponds to σvo, σdo, and σho in FIG. 5, respectively.

That is, the shape of the conventional yoke portion is such that the peak of the outer wall tensile stress, which is the starting point of a crack, and the minimum thickness portion are in agreement with each other, and the yoke portion of the present invention is in FIG. Since the starting point of the crack and the minimum thickness portion are different, implosion hardly occurs.

This can be applied to various cathode ray tube apparatuses having a screen ratio other than 4: 3.
When the screen is horizontally long like 6: 9, the yoke shape is also horizontally long according to the screen as shown in FIG. 11, so that the vicinity 116 of the vertical axis moves in the direction shown by the broken line 117 in FIG. Since the distortion is greater than 4: 3 and the strength of the valve is greatly deteriorated, the effect of employing the present invention is great.

As described above, at least one section perpendicular to the tube axis of the yoke portion is formed in the vertical axis direction and the horizontal direction of the screen in order to reduce the deflection power and ensure the pressure resistance of the vacuum envelope. It has a non-circular shape that forms the maximum outer diameter of the yoke between the axial directions, and at least one of the non-circular cross sections has an angle θi between the horizontal axis and the inner diameter of the maximum yoke, θi,
When the angle between the horizontal axis and the outer diameter of the maximum yoke is θo,
The shape of the yoke is configured so that θiiθo.

At this time, in the cross section perpendicular to the tube axis of the yoke portion, a point on the inner wall of the yoke portion at which the inner diameter of the yoke portion is the largest among the distances between the inner wall of the yoke portion and the outer wall of the yoke portion is determined. The shape of the yoke portion is configured so that the distance from the point on the outer wall of the yoke portion where the diameter becomes maximum is not minimized.
In addition, the rear envelope part which is located between the panel part and the neck part and connects them will be described as being divided into a funnel part and a yoke part. However, there is also a configuration in which a plurality of yoke parts are formed in one tube. Some do not form a funnel. Thus, in the present invention, such a cathode ray tube having a rear envelope configuration is also referred to as a funnel portion.

[0027]

1 to 7, an embodiment of the present invention will be described. Here, FIG. 4 is a schematic cross-sectional view when FIG. 1 is cut along a diagonal axis D along the tube axis Z. The cathode ray tube 10 is connected to a substantially rectangular panel portion 12, a funnel portion 13 connected to the panel portion 12, a yoke portion 14 connected to a small diameter portion of the funnel portion 13, and the yoke portion 14. It has a glass vacuum envelope in which a cylindrical neck portion 15 is arranged along the tube axis Z.

On the inner surface of the panel 12, a phosphor screen 17 composed of red, green, and blue phosphor layers 17R, 17G, and 17B and a shadow mask 19 having a beam transmitting hole near the screen are provided. I have. An electron gun 18 is arranged in the neck 15. A deflection yoke 20 is mounted from the yoke portion 14 to the outside of the neck portion 15.
The electron beam 22 emitted from the electron gun is horizontally and vertically deflected by a vertical deflection magnetic field, and the phosphor screen 17 is horizontally and vertically scanned to display an image.

Here, the deflection reference position 25 is shown in FIG.
(B) As shown in FIG.
When the straight line is connected from 7d to a certain point 0 of the tube axis Z, the angle formed by the two straight lines is the position on the tube axis such that the maximum deflection angle θ specified by the cathode ray tube is the center of deflection. In particular, in the cathode ray tube 10, the yoke portion 14 to which the deflection yoke 20 is mounted is formed in a substantially pyramid shape.

The outer surface of the envelope 16 along the tube axis Z has a substantially S-shaped curve from the funnel 13 to the neck 15, and the boundary between the funnel 13 and the yoke 14 is an inflection of the same curve. Point 23. The deflection yoke 20 is mounted so that the edge 21 on the panel side is located near the inflection point 23, and the substantial yoke portion 14 is formed at least from the connection portion 24 to the neck portion 15 to the edge 21. Become.

FIG. 2 shows the outer shape of the yoke portion 14. A curve 26 represents the maximum outer diameter of the yoke from the connection 24 with the neck 15 to the screen-side end 21 of the deflection yoke 20, and the angle between the horizontal axis and the maximum outer diameter of the yoke 20 is the connection position 24 with the neck. The angle gradually changes from 36.87 ° to 40.0 ° from the vicinity to the yoke portion screen side edge 21. Curve 27 is the outer diameter of the yoke in the major axis direction, and curve 28 is the outer diameter of the yoke in the minor axis direction.

As shown by these curves 26 to 28, the yoke portion 14 has a circular shape substantially the same as the neck portion at the connection portion 24 with the neck portion 15, but the diagonal axis direction approaches the screen side 17. The outer diameter in the major axis and minor axis directions changes gradually with respect to the outer diameter, and the cross section perpendicular to the tube axis has a substantially rectangular shape (non-circular shape). In this case, the aspect ratio of the screen 17 is 4: 3.

Further, in FIG. 6 showing a section perpendicular to the tube axis at the deflection reference position 25 in FIG. 4, the inner wall of the yoke portion is formed so as not to block the beam passage area 126, and the tube axis position O The angle θi between the maximum inner diameter of the yoke and the horizontal axis is the same as the diagonal axis angle of the screen 17 having an aspect ratio of 4: 3, ie, θi = 36.87 °. In this case, the interval between the tube axis position O and the outer wall of the yoke portion is maximum, that is, the angle θO between the maximum yoke outer diameter and the horizontal axis is θO = 39.00 °, and θi ≠ θo.

In comparison with FIG. 5, which shows a cross section perpendicular to the tube axis of the deflection reference position 25 of the conventional yoke portion, the point at which the outer wall tensile stress becomes maximum is the maximum yoke outer diameter position Pdi. In the present invention, the point at which the outer wall tensile stress becomes maximum in FIG. 6 is the maximum yoke outer diameter position Pdi ′, whereas the wall thickness t is t = 3.0 mm. '= 3.3 mm, which is about 10% thicker than the conventional one. That is, the starting point of the crack and the minimum thickness part are different, so that it is possible to configure a shape in which implosion is unlikely to occur. Here, the outer diameter LA of the yoke portion in the horizontal axis direction, the outer diameter SA of the yoke portion in the vertical axis direction, and the maximum outer diameter DA of the yoke portion in the present invention are the same as those of the conventional yoke portion.

Therefore, in the cathode ray tube device having the yoke portion of the present invention as shown in FIG. 6, there is no problem in terms of bulb strength. In addition, since the yoke portion is sufficiently pyramid as shown in FIG. 2 as described above, the deflection power is sufficiently reduced.

Here, the yoke portion is θ0> θi or θ0
<Θi In any case, the thickness of the yoke t at the point where the outer wall tensile stress becomes maximum can be increased, and the pressure resistance can be improved, as compared with the conventional θ0 = θi. However, the effect is greater when θ0> θi as shown in FIG. 6 because the outer cross-sectional shape of the yoke portion approaches a square.

[0037]

According to the yoke portion configuration of the present invention,
Even if the yoke portion is formed into a pyramid, the pressure resistance of the vacuum envelope can be sufficiently ensured, and the deflection power can be effectively reduced, so that a cathode ray tube device that meets the requirements of high luminance and high frequency deflection can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view illustrating an embodiment of a cathode ray tube of the present invention.

FIG. 2 is a curve diagram showing dimensions of an outer diameter in a horizontal axis direction, an outer diameter in a vertical axis direction, and an outer diameter of a maximum yoke portion at a position in a tube axis direction of a yoke portion according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram for displaying a yoke section sectional shape perpendicular to a tube axis.

FIG. 4 is a schematic cross-sectional view when FIG. 1 is cut along a diagonal axis D plane along a tube axis Z.

FIG. 5 is a cross-sectional view for explaining a problem of a conventional yoke portion shape.

FIG. 6 is a cross-sectional view illustrating the shape of a yoke according to the present invention.

FIGS. 7A and 7B are views for explaining a deflection reference position 25 in FIG. 4, wherein FIG. 7A is a cross-sectional view and FIG.

8 (a) is a schematic sectional view, and FIG. 8 (b) is a schematic plan view, for explaining a problem of the conventional cathode ray tube.

9A and 9B illustrate a conventional cathode ray tube in which a yoke portion has a pyramid shape, wherein FIG. 9A is a schematic side view, and FIGS. 9B to 9F are schematic sectional views.

FIG. 10 is a sectional view of a yoke section orthogonal to the tube axis, for explaining stress generated in the pyramid-shaped yoke.

FIG. 11 is a sectional view of a yoke portion orthogonal to the tube axis, for explaining stress generated in the pyramid-shaped yoke at a screen ratio of 16: 9.

[Explanation of symbols]

 10: Cathode ray tube 12: Panel section 13: Funnel section 14: Yoke section 15: Neck section 16: Glass vacuum envelope 17: Phosphor screen 18: Electron gun 20: Deflection yoke 21: Deflection yoke edge 22: Electron beam 23: inflection point 24: connecting part 25: deflection reference position

Claims (4)

[Claims] 1. A display device comprising: a panel portion having at least a phosphor screen on an inner surface; a neck portion having an electron gun disposed on an inner surface facing the screen; and a yoke portion connected to the screen side of the neck portion. A glass vacuum envelope, and a deflection yoke arranged on the outer surface of the vacuum envelope from the yoke to the neck to deflect and scan an electron beam emitted from the electron gun to a substantially rectangular screen area. In the cathode ray tube device configured, the yoke portion extends from a connection position of the neck portion to at least a screen side end of the deflection yoke, and sets a distance between the tube axis and the inner wall of the yoke portion in a cross section perpendicular to the tube axis to the yoke portion. When the distance between the inner diameter, the tube axis and the outer wall of the yoke portion is the outer diameter of the yoke portion, at least the deflection is performed from the neck portion connecting position of the yoke portion. At least one cross section perpendicular to the tube axis up to the screen side end of the screen has a non-circular shape having a maximum yoke outer diameter in a direction between the vertical axis direction and the horizontal axis direction of the screen. The non-circular cross-section has an angle θi between the horizontal axis and the inner diameter of the maximum yoke portion.
The angle between the horizontal axis and the outer diameter of the maximum yoke portion is θo
Wherein: θi ≠ θo. 2. In the section perpendicular to the tube axis of the yoke portion, the distance between the inner wall of the yoke portion and the outer wall of the yoke portion of the non-circular cross section is the largest on the inner wall of the yoke portion. 2. The distance between a point and a point on the outer wall of the yoke at which the outer diameter of the yoke is maximized is not minimum.
The cathode ray tube device as described in the above. 3. The cathode ray tube device according to claim 1, wherein a funnel portion is provided between said panel portion and said yoke portion. 4. When the maximum yoke outer diameter of the non-circular cross section is DA, the yoke outer diameter on the horizontal axis is LA, and the yoke outer diameter on the vertical axis is SA, DA>LA> SA, θo>
2. The cathode ray tube device according to claim 1, wherein the relationship is θi.