JP2000149818A - Cathode ray tube equipped with deflection yoke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce twisting an bending of convergence by mounting a core to the insulating frame of a deflection yoke device by a fittingly bound structure. SOLUTION: A core 7D is fitted in a separator 7A by abutting its inner wall surfaces of both end parts in the (z) direction onto the separator, so as to regulate its movement in the (x), (y) and (z) directions. A margin 10 to crush of an aggregate of many fine protuberances is formed at the same time when the separator 7A is molded on the outer peripheral surface of the separator 7A. The margin 10 to crush is partially crushed by a big force applied when the core 7D is disposed at the designated position in the separator 7A, and after that, elasticity to keep the core 7D at the designated position is applied to the core 7D. By this fittingly bound structure, the core 7A is easily mounted to the separator 7A without having eccentric to the center axis of the neck part of a color cathode ray tube, the position is semi-permanently maintained and magnetic field in a funnel part can be uniformed.

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, and more particularly to an improvement in a deflection yoke device.

[0002]

2. Description of the Related Art In a cathode ray tube, an envelope is composed of a panel unit serving as a display unit, a neck unit having a built-in electron gun structure, and a funnel unit connecting these components smoothly. A deflection yoke device is provided on the outer periphery of the funnel portion near the neck portion of the envelope, and the deflection yoke device causes an electron beam radiated from the electron gun assembly to form a fluorescent light on the inner surface of the panel portion. The body layer is scanned. The deflection yoke device includes a horizontal deflection coil, a vertical deflection coil, an insulating frame (separator) for supporting and insulating these coils, and a core arranged to cover them. The electron beam from the electron gun assembly is deflected by the magnetic field in the funnel formed by the horizontal deflection coil, the vertical deflection coil, and the core, and scans the phosphor layer surface.
Here, the attachment of the deflection yoke device to the funnel is
Since it directly affects the magnetic field distribution in the funnel portion, it is required to arrange the core without eccentricity and inclination even up to the core, and this requirement was almost satisfied.

[0003]

However, in recent years, in order to improve the sensitivity, a cathode ray tube having a thin neck (for example, φ22 to 25 compared to the conventional neck diameter of φ29) has been developed. Has become known. And
In this case, since the magnetic field intensity of the deflection yoke device with respect to the electron beam in the funnel becomes large, it has been found that a uniform deflection magnetic field cannot be obtained in the funnel even with a slight eccentricity and inclination of the core. . This can be confirmed particularly by the occurrence of local waviness (concentration shift) on the display surface in the convergence characteristic related to the concentration of the electron beams of three colors. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cathode ray tube including a deflection yoke device with less convergence bend.

[0004]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows. That is, a cathode ray tube including a deflection yoke device, wherein the deflection yoke device has a fitting structure in which the core is attached to the insulating frame. The cathode ray tube configured as described above can be mounted without a so-called "play" on the core with respect to the insulating frame.
This makes it easier to attach the core to the center axis of the neck without eccentricity, and once it can be attached, its position can be held semi-permanently. For this reason, the magnetic field in the funnel portion by the deflection yoke device can be made uniform, and the occurrence of convergence bend can be avoided.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a cathode ray tube according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing one embodiment of a cathode ray tube according to the present invention. In the figure, first, there is an envelope 1 of a color cathode ray tube. This envelope 1 includes a panel portion 1A serving as a display portion of the cathode ray tube, a neck portion 1B containing the electron gun assembly 2, and a panel 1 Part 1
Funnel 1C that smoothly connects A and neck 1B
It is composed of Here, in this embodiment, the neck portion 1B is configured to be considerably thinner than the size of the panel portion 1A, and the diameter thereof is, for example, φ22 to 25.

The electron gun assembly 2 built in the neck 1B
The electron gun 3 emits a red (R), green (G), and blue (B) light-emitting electron beam 3 toward the phosphor layer 4 formed on the inner surface of the panel section 1A. ing. In the phosphor layer 4, three phosphors for red (R), green (G), and blue (B) emission are arranged adjacent to each other, and each phosphor constitutes one pixel for color. Are formed over the entire area of the phosphor layer.

Further, a shadow mask 5 is arranged inside the panel section 1A so as to face the inner wall surface on which the phosphor layer 4 is formed, and the shadow mask 5 faces one color pixel. Thus, electron transmission holes are respectively formed.

Further, an inner shield 6 for reducing an external magnetic field is arranged inside the funnel section 1C. With this inner shield 6, each electron beam from the electron gun assembly 2 is not affected by the external magnetic field. It can pass through a regular electron transmission hole of the shadow mask 5.

On the other hand, on the outside of the envelope 1, its neck 1
A deflection yoke device 7 is attached so as to surround the funnel portion 1C close to B. The deflection yoke device 7 incorporates a horizontal deflection coil and a vertical deflection coil, as will be described later, and drives the electron gun assembly 2
Each electron beam 3 is deflected in the horizontal direction and the vertical direction, and is scanned on the phosphor layer 4.

FIG. 2 is a configuration diagram showing the configuration of the deflection yoke device 7. As shown in FIG. 1A, in the deflection yoke device 7, a neck portion 1B of a cathode ray tube envelope 1 is positioned in a z direction in the drawing, and a periphery of a funnel portion 1C close to the neck portion 1B is formed. It is arranged so as to cover.

First, the deflection yoke device 7 includes an insulating frame (separator) 7A having a tubular shape (flapper shape) substantially conforming to the shape of the funnel portion 1C of the envelope 1 of the cathode ray tube.
The separator 7A is made of, for example, a synthetic resin material, and is formed by molding. And
On the inner wall of the separator 7A, a horizontal deflection coil 7B is arranged almost over the entire area. Also, on the outer periphery of the separator 7A, on the large diameter portion side (panel portion side).
Is provided with a vertical deflection coil 7C. Further, a core 7D is arranged on the outer periphery of the separator 7A so as to cover the separator 7A.

Here, as shown in FIG. 1B, the horizontal deflection coil 7B is composed of two coils separated by a zx plane, and is integrated after attaching each to the funnel 1C. It is configured as a tubular (horn) coil.

Further, as shown in FIG. 1C, the separator 7A is made of a member divided into two parts with the yz plane as a boundary. (Trumped).

The vertical deflection coil 7C is shown in FIG.
As shown in FIG. 7, the coil is divided into two parts with the yz plane as a boundary, and after being attached to the separator 7A, they are integrated into a single coil.

Further, as shown in FIG. 2E, the core 7D is made of a member divided into two parts with the xz plane as a boundary, and after being attached to the separator 7A, they are integrated into one member. It is configured as:

FIG. 2A shows that the respective cores are integrated by a mounting bracket 8 at adjacent portions. In this deflection yoke device 7, an auxiliary coil 7E and a terminal plate 7F are formed in a small diameter side (electron gun structure side) portion.

FIG. 3 is a sectional view showing the positional relationship between the separator 7A and the core 7D when cut along the yz plane in FIG. As is clear from the figure, the movement of the core 7D in the x, y, and z directions is restricted by fitting the end face and the inner wall surface at both ends in the z direction in the figure into contact with the separator 7A. Has been arranged.

A so-called “crush margin 10” is formed on the outer peripheral surface of the separator 7A. The 'crushing margin 10' is formed at the same time when the separator 7A is formed by molding, and is composed of a group of many fine projections.

By providing such a "shrinking margin 10", when the core 7D is arranged at a predetermined position with respect to the separator 7A, the "crushing margin 10" is applied by a large force applied by the arrangement. Is partially crushed, and thereafter, elasticity for maintaining the core in a predetermined position is applied to the core 7D. Such a structure is generally referred to as a fitting spring structure.

With this configuration, it becomes easy to attach the core 7D to the separator without eccentricity with respect to the center axis of the neck portion 1B.
If so attached, the position can be held semi-permanently.

It has been confirmed that the degree of eccentricity of the core 7D of the deflection yoke device 7 thus configured can be suppressed to about 0.1 mm or less even if it is slightly eccentric. For this reason, the magnetic field in the funnel portion 1C by the deflection yoke device 7 can be made uniform,
The occurrence of convergence bend can be avoided.

From this, it is not always necessary to form the 'crushing margin 10' on the separator 7A over the entire outer peripheral surface thereof, and at least a portion in contact with the core 7D is sufficient.

FIGS. 4A to 4C are diagrams showing the magnetic field distribution in the funnel 1C which can be achieved by the structure of the present invention. Each of the figures is a magnetic field distribution diagram corresponding to the position of the deflection yoke device in the z-axis direction.
As is clear from these figures, it can be seen that uniformity of the magnetic field distribution is ensured.

For comparison, FIGS. 5A to 5C show the case of a conventional deflection yoke device. In the conventional deflection yoke device, the attachment of the core 7D to the separator 7A is what is called a so-called clearance structure, and the core has a structure in which a so-called 'play' is slightly generated.

FIG. 6 shows convergence characteristics that can be achieved by the configuration of the present invention. FIG. 7 shows a conventional convergence characteristic for comparison. From this, it can be seen that the convergence characteristics according to the present invention have not confirmed the so-called 'undulation' conventionally observed.

[0026]

As is apparent from the above description,
According to the cathode ray tube of the present invention, convergence bend can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of a color cathode ray tube according to the present invention.

FIG. 2 is a configuration diagram showing one embodiment of a deflection yoke device provided in a color cathode ray tube according to the present invention.

FIG. 3 is a main part configuration diagram showing one embodiment of a deflection yoke device provided in the cathode ray tube according to the present invention.

FIG. 4 is a diagram showing a magnetic field distribution in a funnel portion of a cathode ray tube according to the present invention.

FIG. 5 is a diagram showing a magnetic field distribution in a funnel portion of a conventional cathode ray tube.

FIG. 6 is a diagram showing convergence characteristics of a cathode ray tube according to the present invention.

FIG. 7 is a diagram showing convergence characteristics of a conventional cathode ray tube.

[Explanation of symbols]

7: deflection yoke device, 7A: separator, 7B: horizontal deflection coil, 7C: vertical deflection coil, 7D: core, 10 ...
Crush it.

Claims (2)

[Claims] 1. A cathode ray tube comprising a deflection yoke device, comprising: a deflection yoke device, wherein the deflection yoke device has a fitting structure in which a core is attached to an insulating frame. tube. 2. A cathode ray tube comprising a deflection yoke device, wherein a crushing margin is provided at a contact portion of the insulating frame with the core.