JPH11273591A - Cathode-ray tube apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode-ray tube apparatus capable of retaining sufficiently high atmospheric pressure resistance of a vacuum outer casing even if the yoke part is made to be a pyramid shape, efficiently lowering the deflecting electric power consumption, and satisfying the demands of high brightness and high frequency deflection. SOLUTION: The yoke part, which is a region where a defection yoke is installed in a funnel part of a vacuum outer casing of a cathode-ray tube having an approximately rectangular phosphor screen is made to be an approximately pyramid shape and in a cross-section of the yoke part 14 vertical to the tube axis, corner parts 115a, 115b, 116a, 116b, 118a, 118b are formed in at least in the longer sides or the shorter sides besides the rectangular corners.

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 cathode ray tube, such as a color picture tube, has a glass vacuum envelope comprising a substantially rectangular panel having a display portion, a funnel-shaped funnel connected to the panel, and a cylindrical neck connected to the funnel. Contains.

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, if the neck diameter and the outer diameter of the yoke are further reduced, the phosphor screen having the maximum deflection angle is obtained. The electron beam directed toward the diagonal portion of the phosphor collides with the inner wall of the yoke portion, and a portion where the electron beam does not collide is formed on the phosphor screen.

Therefore, in the conventional cathode ray tube, there is a limit in reducing the deflection power by reducing the neck diameter and the outer diameter of the yoke. Further, if the electron beam keeps colliding with the inner wall of the yoke, the temperature of the glass rises 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. 10A 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. As for the cathode ray tube 101, the yoke portion 110 of the funnel 103 on which the deflection yoke is mounted is moved from the neck 104 side to the panel 102 as shown in the cross-sections BB to FF of the cathode ray tube 101 in FIGS. 1 shows a shape which gradually changes from a circle to a substantially rectangular shape.

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, as for the cathode ray tube whose outer surface shape is twice or more the effective diameter of the screen, the relationship with the yoke shape was unclear due to the relationship with the envelope strength.

[0015]

As described above, in recent years, reduction in the deflection power and leakage magnetic field of a cathode ray tube has been demanded. However, the reduction in the brightness and the high frequency required for OA equipment such as HDTV and PC have been demanded. It is extremely difficult to perform the process while satisfying the requirements. 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.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. 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 can be effectively reduced. Therefore, it is an object of the present invention to configure a cathode ray tube device which satisfies the requirements of high luminance and high frequency deflection.

[0017]

According to the present invention, there is provided a panel having at least a substantially rectangular phosphor screen on an inner surface thereof,
A neck portion having an electron gun disposed on the inner surface thereof facing the screen, a glass vacuum envelope including a yoke portion connected to the screen side of the neck portion, and the vacuum from the yoke portion to the neck portion. An electron beam emitted from the electron gun is disposed on the outer surface of the envelope, and the electron beam emitted from the electron gun is deflected and scanned in the screen area. When at least up to the vacuum envelope position corresponding to the screen side end of the deflection yoke, and a space between the tube axis and the outer surface of the yoke portion is a yoke portion outer diameter in a cross section perpendicular to the tube axis of the vacuum envelope. At least one section of the yoke portion perpendicular to the tube axis has a maximum yoke outer diameter in a direction between a vertical axis direction and a horizontal axis direction of the screen. It has a non-circular shape, the non-circular cross-section is intended to obtain a cathode ray tube which is a substantially polygonal shape having at least six corners.

At least one cross section perpendicular to the tube axis of the outer surface of the yoke portion has a corner formed by an arc having a radius of curvature of 20 mm or less, thereby obtaining a cathode ray tube device.

Further, at least one cross section of the outer surface of the yoke portion perpendicular to the tube axis is constituted by at least four arcs or straight lines between a horizontal axis direction and a vertical axis direction. Is what you get.

The cathode ray tube apparatus according to claim 1, wherein at least one cross section of the outer surface of the yoke portion perpendicular to the tube axis has a starting point of a tensile stress at least in a direction other than a diagonal axis direction of the screen. Is what you get.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention relates to a cathode ray tube having a substantially pyramid-shaped yoke having a substantially rectangular cross section perpendicular to the tube axis, in addition to four corners of a rectangular shape. A corner is formed on at least one of the long side and the short side.

For comparison with the present invention, FIG. 11 shows a conventional yoke portion 110 having an outer surface having a cross section perpendicular to the tube axis. In this non-circular cross section, the horizontal axis of the screen from the tube axis,
Assuming that the distances to the outer surface of the yoke are LA, SA, and DA on the vertical axis and the diagonal axis, respectively, LA and SA are smaller than DA in the pyramid-shaped yoke, and consequently deflection near the horizontal and vertical axes. The deflection power can be reduced by moving the coil closer to the electron beam. Here, the diagonal axis distance DA having the maximum diameter is in the diagonal axis direction of the screen, but may not exactly match. Note that the smallest one of these three axes is defined as the vertical axis.

Conventionally, shapes other than the above-described three axes have an arc having a center on the horizontal axis and a radius Rh and an arc having a center on the vertical axis and a radius Rv and having a center near a diagonal axis and a radius Rd. The shape was connected by an arc.

As described above, the closer the cross section of the yoke section is to a rectangular shape, the more the deflection power can be reduced, but the strength required for safety as a vacuum envelope cannot be maintained. This is shown in FIG.
As shown in FIG. 1 (b), the flat yoke portion near the horizontal axis 115 and the vertical axis near 116 are distorted by the atmospheric pressure load F as indicated by a broken line 117 in the drawing, so that the compressive stress .sigma. σv0 occurs. On the outer surface near the yoke diagonal axes 118a to 118d, a large tensile stress σd0 is generated.
Approximately through 118d was a starting point, cracked and implosion was likely to occur.

That is, in the conventional pyramid-shaped yoke portion, when viewed in a cross section perpendicular to the tube axis, the outer surface shape has three radii Rh, Rv, and Rd as shown in FIG. As shown in FIG. 11 (b), in the outer surface shape of the yoke portion, four substantially rectangular corner portions 118a to 118d near the diagonal axis were formed. Therefore, the tensile stress is concentrated at the four corners, and slightly exceeds the maximum stress value of 1200 psi, which is a guide when designing a general envelope at this position.

Here, in one embodiment of the present invention, FIG.
As shown in (a), for example, the outer surface shape of the non-circular yoke portion 14 on the screen side has a radius Rh1 between a horizontal axis and a vertical axis.
It consists of five circles, Rh2, Rd, Rv2, and Rv1. When the yoke portion is configured in this manner, the flat portion (the interval between adjacent corner portions) that is likely to be distorted with respect to the atmospheric pressure as shown in the figure is from Lv (Lh) to Lv '(Lh'). Therefore, the amount of distortion (the difference between the solid line and the broken line 117) is reduced as shown in FIG. Also, as shown in the figure, the corner portions 115a, 115b, 116a, 116b, 118 of the yoke portion
Although tensile stress is generated at a, 118b, 118c, and 118d, stress concentration is also dispersed because the number of corners is eight.

That is, the maximum stress value can be reduced by increasing the corners of the outer surface of the yoke part, and even if the yoke part is formed into a pyramid, it has the same explosion-proof characteristics as a generally widely used conical yoke part tube. Can be. Here, the eight corners provided in FIG. 4A are actually rounded to some extent, and represent arc portions having very small radii of curvature Rd, Rv1, and Rh1. At this time, it is desirable that the radius of curvature Rd constituting the diagonal axis corner in FIG. 11 is substantially the same as the radius of curvature Rd in the diagonal section in FIG. In FIG.
Are connected by arcs with large radii of curvature Rh2 and Rv2,
This part may be connected not by a circular arc but by a straight line.

In the conventional pipe shown in FIG. 3, the maximum radius of curvature of four diagonal portions corresponding to the corners of the yoke is 10 to 10.
20 mm. In the case where a corner is added in addition to the diagonal as in the present invention, a corner having a radius of curvature equal to, or more desirably smaller than, a conventional one can be provided. Therefore, the very small radius of curvature Rd, Rv provided in FIG.
1, Rh1 may be 20 mm, and may be smaller than that.

Further, as shown in FIG. 5C, when the yoke part 14 'is formed, the yoke part can be made smaller than the conventional yoke part shape 14 (110 in FIG. 11), so that the sensitivity is further improved. The effect is expected.

This can be applied to various cathode ray tube apparatuses having a screen ratio other than 4: 3.
In the case where the yoke is horizontally long as shown in FIG. 6: 9, the shape of the yoke is also horizontally long according to the screen as shown in FIG. 8, so that the vicinity 116 of the vertical axis is shifted in the direction shown by the broken line 117 in FIG.
The distortion is larger than the screen ratio of 4: 3 in FIG. 1B, and the strength of the envelope is greatly deteriorated, so that the effect of adopting the present invention is great. For example, distortion can be reduced by providing the corners 121a and 121b on the vertical axis to narrow the interval between the flat portions 122.

As described above, as a structure for reducing the deflection power and ensuring the pressure resistance of the vacuum envelope, the outer shape of at least one cross section perpendicular to the tube axis of the yoke portion is determined in the vertical axis direction of the screen. And some direction D between the horizontal axis direction
(May coincide with or slightly deviate from the diagonal axis of the screen.)
The non-circular shape configures the yoke portion shape to be a rounded, substantially polygonal shape having at least six corners. That is, if corners are formed on all of the long side and the short side of the outer surface shape of the cross section, there are eight corners. However, the short side may be omitted because the interval is short, and in this case, there are six corners. .

At this time, the shape of the yoke portion is such that at least one cross section of the outer surface of the yoke portion perpendicular to the tube axis has a substantially polygonal shape having at least six arcs (corners) having a radius of curvature of 20 mm or less. Constitute.

At this time, at least one section perpendicular to the tube axis on the outer surface of the yoke portion has at least four arcs or straight lines (radius R) between the horizontal axis direction and the vertical axis direction.
h, Rd, Rv2, Rv1).

At this time, the yoke portion is configured such that at least one cross section perpendicular to the tube axis on the outer surface of the yoke portion has a starting point of tensile stress at least in a direction other than the screen diagonal axis direction.

[0035]

1 to 7, an embodiment of the present invention will be described. Here, FIG. 3 is a schematic cross-sectional view when FIG. 1 is cut along the diagonal axis D along the tube axis Z, and a deflection yoke is added in the drawing.

A cathode ray tube 11 shown in FIG. 3 has a substantially rectangular glass panel portion 12, a funnel-shaped glass funnel portion 13 connected to the panel portion 12, and a yoke having a small diameter portion of the funnel portion 13. Part 14 and this yoke part 1
4 is connected to the cylindrical glass neck 15 by the tube axis Z.
Has a vacuum envelope 16 arranged along. Sign 2
3 is a screen side portion of the funnel portion 13 and the yoke portion 1
4 shows the connecting part of FIG.

On the inner surface of the panel 12, a phosphor screen 17 and a shadow mask 19 having a beam transmitting hole close to the screen are provided. In this case, the aspect ratio of the screen 17 (length on the horizontal axis vs. length on the vertical axis) is M: N = 4: 3. 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 deflected in the horizontal and vertical directions by the horizontal and vertical deflection magnetic fields generated, and the phosphor screen 17 is horizontally and vertically scanned to form an image display structure. Have been. Here, the deflection reference position 25 is defined as two straight lines when a straight line is connected from a screen diagonal opposite end 17d across the tube axis to a point O of the tube axis Z as shown in FIGS. This is a position on the tube axis where the angle formed is the maximum deflection angle θ defined by the cathode ray tube, and is a position that is the center of deflection.

FIG. 2 shows the outer shape of the yoke section 14 in a section including the tube axis. A curve 26 is the maximum outer diameter of the yoke portion from the connection portion 24 to the neck portion 15 to the screen side end 21 of the deflection yoke 20 and substantially coincides with the screen diagonal axis D direction. The yoke portion 14 is substantially the neck portion 1
5 to the position of the envelope corresponding to the end of the deflection yoke 20 on the screen side. Also, curve 27
Is the outside diameter of the yoke in the long axis (horizontal axis) direction, and curve 28 is the outside diameter of the yoke in the short axis (vertical axis) direction. These curves 26
As shown in FIGS. 28 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 becomes longer with respect to the outer diameter in the diagonal axis direction as approaching the screen 17. The outer diameter in the axial and minor axis directions is gradually reduced.

In the cross section perpendicular to the tube axis at the deflection reference position 25 (FIG. 3), the shape other than the above three axes is five between the horizontal axis and the vertical axis (first quadrant) shown in FIG. It has a circular configuration, and has eight corners when viewed in four quadrants. In other words, as mentioned earlier in this part,
Since the flat portion (the distance between adjacent corners) where distortion easily occurs with respect to the atmospheric pressure is reduced to about half, the amount of distortion (difference between the solid line and the broken line) is reduced, and the corner of the yoke is reduced to the conventional four.
By increasing the number from eight to eight, the stress concentration is dispersed, so that the maximum stress value is greatly reduced and the valve strength necessary for safety can be secured. Here, since the yoke portion is sufficiently pyramid as shown in FIG. 2 as described above, the deflection power is formed by forming the deflection yoke separator and the core portion in a substantially pyramid shape along the yoke portion in FIG. Is also sufficiently reduced.

As another embodiment, as shown in FIG. 6, when viewed in a section perpendicular to the tube axis of the yoke portion, the outer surface shape is defined as four circles (first quadrant) between the horizontal axis H and the vertical axis V (first quadrant). Rh, R
d, Rv2, Rv1), that is, six corners (116a, 116b, 118a, 118) in which corners 116a, 116b are added only to the long vertical axis V of the flat part.
The hexagonal yoke portions b, 118c and 118d) are also expected to have a sufficient stress reduction effect. This is an effective shape especially in the case of the landscape screen 16: 9.

In another embodiment, as shown in FIG. 7, a pair of corners 18a, 18b, 18c, 18 are formed at four corners of a rectangle when viewed in a section perpendicular to the tube axis of the yoke.
d, 18e, 18f and 18g, 18h to form
The corners are increased near the diagonal axis where the tensile stress is concentrated to relieve the stress.

In addition, the same effect can be expected even if numerous corners are provided innumerably. Further, the arc may be a straight line having an infinite radius.

[0044]

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 perspective view of a cathode ray tube according to an embodiment of the present invention as viewed from the rear.

FIG. 2 is a curve diagram showing a horizontal axis direction outer diameter, a vertical axis direction outer diameter, and a maximum yoke part outer diameter of a yoke part according to an embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view of the upper half when FIG. 1 is cut along a diagonal axis D plane along a tube axis Z.

FIG. 4 (a) is a schematic cross-sectional view for explaining the outer shape of the pyramid-shaped yoke portion of the present invention in a cross section perpendicular to the tube axis, and FIG. 4 (b) illustrates the stress generated in this yoke portion. Schematic to do,

FIG. 5 is a schematic diagram comparing the present invention with a conventional yoke portion shape.

FIG. 6 is a schematic sectional view showing another embodiment of the present invention.

FIG. 7 is a schematic sectional view showing another embodiment of the present invention.

FIG. 8 is a view for explaining stress generated in a pyramid-shaped yoke of a horizontally long screen 16: 9.

FIG. 9 is a diagram illustrating a deflection reference position.

FIG. 10 (a) is a side view showing a conventional cathode ray tube,
(B) thru | or (f) are schematic sectional drawing which cut | disconnects and shows (a) along BB line-FF line.

11A is a schematic cross-sectional view for explaining an outer shape of a conventional pyramid-shaped yoke portion in a cross section perpendicular to a tube axis, and FIG. 11B is a diagram for explaining stress generated in the yoke portion. Schematic for.

[Explanation of symbols]

11: 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 screen side end 22: electron Beam 24: Connection with neck 25: Deflection reference position 115a, 115b, 116a, 116b, 118a to 118d: Corner

Claims (4)

[Claims] 1. A panel having at least a substantially rectangular phosphor screen on an inner surface thereof, a neck portion having an electron gun disposed to face the screen, and a yoke portion connected to the screen side of the neck portion. 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 onto the screen. In the cathode ray tube device, the yoke portion extends from a connection position of the neck portion to at least the vacuum envelope position corresponding to a screen side of the deflection yoke, and has a tube axis and the yoke in a cross section perpendicular to the tube axis. When the space between the outer surfaces is the yoke outer diameter,
At least one cross section of the yoke portion perpendicular to the tube axis has a non-circular shape having a maximum yoke portion outer diameter in a direction between a vertical axis direction and a horizontal axis direction of the screen, and the non-circular cross section Is a generally polygonal shape having at least six corners. 2. The cathode ray tube device according to claim 1, wherein at least one cross section of the outer surface of the yoke portion perpendicular to the tube axis has the corner formed by an arc having a curvature radius of 20 mm or less. 3. The at least one cross section of the outer surface of the yoke portion perpendicular to the tube axis is formed of at least four arcs or straight lines between a horizontal axis direction and a vertical axis direction. The cathode ray tube device as described in the above. 4. The cathode ray tube apparatus according to claim 1, wherein at least one cross section of the outer surface of the yoke portion perpendicular to the tube axis has a starting point of a tensile stress at least in a direction other than a diagonal axis direction of the screen. .