JP2003036801A - Color cathode ray tube with deflection yoke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a leakage magnetic field of a deflection coil without deflecting current. SOLUTION: It provides a loop coil 18 to generate a cancel magnetic field for reducing the leakage magnetic field LX leaked to an outer of the deflection yoke from the deflection coil 13A, winding a part of a deflection current supplying wire 19 for supplying the deflecting current to the deflection coil 13A, to a outer area of deflection unit 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color cathode ray tube for displaying a color image, and more particularly to a color cathode ray tube with a deflection yoke in which an unnecessary magnetic field blown out from the deflection yoke is reduced.

[0002]

2. Description of the Related Art A color cathode ray tube used as a monitor tube for a color television picture tube or information equipment emits an electron beam and a panel portion having a phosphor screen (phosphor screen, hereinafter simply referred to as screen) on its inner surface. A vacuum envelope is constructed by connecting a neck portion accommodating the electron gun with a funnel-shaped funnel portion. In a color cathode ray tube having such a vacuum envelope, the best convergence can be obtained with good focusing characteristics (focus characteristics) over the entire phosphor screen forming the screen, and high resolution without color misregistration. Therefore, a magnet assembly composed of a magnet having a plurality of magnetic poles is arranged on the outer wall of the neck portion accommodating the electron gun, and the orbit of the electron beam is corrected by the magnetic field.

Further, a horizontal deflection coil and a vertical deflection coil for deflecting and scanning the electron beam emitted from the electron gun in the horizontal and vertical directions are provided, and a rotation correction for correcting the rotation of the image (raster) on the screen is provided. Deflection current modulator (Magnetic Current M) that corrects raster distortion in the central area of the coil and screen, so-called inner pin.
A deflection unit equipped with an odulator (MCM) or the like is installed from the neck portion to the funnel portion.

FIG. 4 is a side sectional view for schematically explaining a structural example of a color cathode ray tube with a deflection yoke in which a deflection unit is mounted on the color cathode ray tube. This color cathode ray tube with a deflection yoke is a panel unit 1 coated with a phosphor screen 4 which constitutes a screen.
A funnel-shaped funnel portion (also referred to as a cone portion) 3 connecting the neck portion 2 and the panel portion 1 and the neck portion 2 constitutes a vacuum envelope, and the funnel portion 3 is formed from the outer circumference of the neck portion 2.
A magnet assembly 12 and a deflection unit 15 having a deflection yoke 16 having a deflection coil 13 are mounted on the exterior of the deflection unit 15.

Inside the neck portion 2, there are three electron beams B.
The electron gun 11 that emits in-line is housed.
The phosphor screen 4 formed on the inner surface of the panel portion 1 has phosphors of three colors applied in a mosaic shape, and a shadow mask structure 5 for color selection is installed in the vicinity of the phosphor screen 4. The shadow mask structure 5 has a support frame 7 that holds the shadow mask 6, and is suspended and held by being mounted on stud pins 9 that are erected on the inner wall of the skirt portion of the panel portion 1 by suspension springs 8. A magnetic shield 10 for shielding an external magnetic field is provided on the electron gun side of the shadow mask structure 5.
Is installed. An explosion-proof band 14 is fastened to the outer wall of the panel 1.

The deflection yoke forming the deflection unit generates a deflection magnetic field having a predetermined pattern for deflecting the electron beam emitted from the electron gun in the panel portion 3 of the vacuum envelope in two directions, horizontal and vertical. Therefore, in the deflection yoke, only the deflection magnetic field generated inside the funnel portion 3 contributes to the deflection of the electron beam. However, the magnetic field also blows out from the deflection yoke to the outside of the vacuum envelope. This magnetic field is called a leakage magnetic field, and is an unnecessary magnetic field originally.

FIG. 5 is an explanatory view of an example of the configuration of a deflection unit that is packaged in a color cathode ray tube and an example of a pattern of generation of an unnecessary magnetic field generated outside the vacuum envelope. This deflection unit 15
The deflecting yoke 16 incorporated in the device has a large-diameter portion (front end: front surface) on the arrow P side and a small-diameter portion (rear end: rear surface) on the arrow G side that is the electron gun side. ing. A horizontal deflection coil 13A is arranged inside thereof, and a vertical deflection coil 13B is arranged outside thereof via a separator (not shown). Further, a core (not shown) made of ferrite or the like is arranged outside the vertical deflection coil. The horizontal deflection coil 13A is shown only in the portions formed at the front end and the rear end of the deflection yoke 16.

A rotation correction coil 22 is mounted on the end of the deflection yoke 16 on the large diameter side, and a magnet assembly combining the 4-pole or 6-pole magnets shown in FIG. 4 on the small diameter side. The solid 12 is attached. In the deflection yoke having such a configuration, in particular, since a relatively large current having a horizontal deflection frequency is supplied to the horizontal deflection coil 13A, the magnetic field LX is blown to the outside as illustrated.
This is called a low frequency leakage magnetic field or simply a leakage magnetic field.

[0009]

The leakage magnetic field LX occupies most of the leakage magnetic field of the color cathode ray tube and is strictly limited by the so-called TCO standard. Since the above standard may not be satisfied depending on the mounted monitor, it is necessary to have a sufficient margin at the shipping stage of the color cathode ray tube with the deflection yoke.

As a method of reducing such a leakage magnetic field, there is a method of generating and canceling a magnetic field in the direction opposite to the leakage magnetic field. FIG. 6 is an explanatory diagram of a configuration example of a deflection unit showing an example of a conventional technique for reducing a leakage magnetic field. In the figure, the same reference numerals as those in FIG. 5 correspond to the same functional parts. In this example, a cancel coil 23 is provided in the vicinity of the horizontal deflection coil 13A at the front end of the deflection yoke 16 to flow a horizontal deflection current. Is being reduced.

However, the provision of such a cancel coil requires an increase in the deflection power, and if the cancel coil is simply provided to divert the deflection current from the deflection circuit,
Since the deflection size becomes small, it is necessary to increase the deflection current to flow in the cancel coil 23. Therefore, the power consumption of the entire color cathode ray tube increases. Further, it is possible to improve the deflection sensitivity to reduce the deflection current itself, but it is difficult to sufficiently reduce the leakage magnetic field.

An object of the present invention is to provide a color cathode ray tube with a deflection yoke in which the leakage magnetic field in such a color cathode ray tube is reduced without increasing the deflection current.

[0013]

To achieve the above object, according to the present invention, a part of a deflection current supply line for supplying a deflection current from a deflection circuit to a deflection coil is provided outside a vacuum in an exterior region of the deflection unit. It is characterized in that it is a loop coil for generating a canceling magnetic field that reduces the leakage magnetic field that is wound around the envelope and blows out from the deflection coil to the outside of the deflection yoke. The typical constitution of the present invention is as follows.

(1): A vacuum envelope is formed by a panel section having a phosphor screen forming a screen, a neck section accommodating an in-line electron gun for emitting an electron beam, and a funnel section connecting the panel section and the neck section. And a deflection yoke having a deflection coil for deflecting the electron beam in two directions, horizontal and vertical, and a display screen on the phosphor screen by correcting the trajectory of the electron beam. A magnet assembly for optimizing color purity and convergence of the deflection yoke, and a deflection current supply line for supplying a deflection current to a deflection coil forming the deflection yoke is provided in the vacuum region in the exterior region of the deflection unit. To generate a canceling magnetic field that winds the envelope and reduces the leakage magnetic field blown from the deflection coil to the outside of the deflection yoke. Was Pukoiru.

(2): The loop coil is preferably wound around the neck of the color cathode ray tube. The deflection coil has a horizontal deflection coil and a vertical deflection coil which are stacked with a separator interposed therebetween, and the loop coil is wound around the separator on the neck side. The winding direction is a direction in which a magnetic field that cancels the leakage magnetic field generated from the deflection coil is generated.

The loop coil is a part of the deflection current supply line of the horizontal deflection coil extending from the deflection circuit to the deflection yoke. A large current of about 10 A _PP normally flows through the horizontal deflection coil. The canceling magnetic field generated from the loop coil cancels most or a considerable portion of the leakage magnetic field, so that the above standard can be satisfied. It should be noted that the present invention is not limited to the above-described configuration and the configurations of the examples described later, and various modifications can be made without departing from the technical idea of the present invention.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described in detail with reference to the drawings of the embodiments. FIG. 1 is a side view of a main part of a deflection unit for explaining an embodiment of a color cathode ray tube with a deflection yoke of the present invention. 2 is shown in FIG.
FIG. 3 is an explanatory view of a wound state of the loop coil in FIG. Figure 1
2, the deflection yoke 16 is a horizontal deflection coil 13A.
And a vertical deflection coil 13B.
Are separated by. Horizontal deflection coil 13A at the rear end
A loop coil 18 in which a deflection current supply line 19 for supplying a deflection current is wound one turn is provided. Note that reference numeral 16A indicates a tightening fitting 16A, and reference numeral 22 indicates a rotation correction coil.

The loop coil 18 is formed by winding a horizontal deflection current supply line 19 in the neck portion for one turn. That is, one end 19A of the horizontal deflection current supply line 19 has a connector 20 for connecting the horizontal deflection current supply line 19 to a deflection circuit (not shown), and the other end 19B has a terminal plate (not shown) for collecting the terminals of the horizontal deflection coil 13A. It is connected to the terminal of the horizontal deflection coil 13A (described in FIG. 3). The neck portion 2 is rotated around a part of the horizontal deflection current supply line 19 as a loop. The separator is not shown in FIG.

The loop coil 18 is a horizontal deflection coil 13A.
It is wound in such a direction as to generate a magnetic field in a direction that cancels the leakage magnetic field generated from. This loop coil 18 is effective in the region where the deflection yoke 16 is exteriorly mounted in the tube axis direction, but if it is wound around the neck portion at the rear end of the deflection yoke 16, the loop diameter can be reduced. , Efficient. When a horizontal deflection current flows through the loop coil 18, a magnetic field in a direction canceling the leakage magnetic field LX is generated, and a part or most of the leakage magnetic field from the horizontal deflection coil is canceled, and the above-mentioned TCO standard WO is satisfied. The leakage magnetic field is reduced up to. FIG. 1 schematically shows a leakage magnetic field that is mostly canceled and reduced by the magnetic field of the loop coil 18. As a result, the TC
It is possible to obtain a color cathode ray tube with a deflection yoke that secures a sufficient leakage magnetic field margin with respect to the O standard.

FIG. 3 is a side view of a deflection unit for explaining one embodiment of the present invention in detail. The same reference numerals as those in FIGS. 1 and 2 correspond to the same functional parts. Reference numeral 12 indicates a magnet assembly, reference numeral 15A indicates a terminal plate, and reference numeral 17 indicates a stem socket. A part of the deflection current supply line 19 is wound around the neck portion around the separator 21 of the deflection yoke 16 for one turn. One end 19A of the deflection current supply line 19 is connected to a deflection circuit, and the other end 19B is connected to a terminal of the horizontal deflection coil by a terminal plate 15A.

As a result, it is possible to obtain a color cathode ray tube with a deflection yoke which has a sufficient margin with respect to the above-mentioned ITO standard. The loop coil 18 is not limited to the one installed at the rear end of the deflection yoke 16 shown in the figure, and has an effect of reducing the leakage magnetic field as long as it is in the exterior range of the deflection unit 15 in the tube axis ZZ direction. The number of turns of the loop coil is not limited to one turn, but may be two or more turns depending on the magnitude of the deflection current, the required cancellation amount of the leakage magnetic field, and the like.

Further, it is possible to reduce the leakage magnetic field generated from another coil such as a rotation correction coil in addition to the deflection coil by changing the size and installation position of the loop of the loop coil. Further, the present invention is not limited to the color cathode ray tube, but can be applied to other cathode ray tubes having the same deflection yoke.

As described above, according to the embodiment of the present invention, the deflection yoke having a leakage magnetic field margin capable of reducing the leakage magnetic field of the deflection coil in various cathode ray tube devices including the color cathode ray tube device and sufficiently clearing the TCO standard. It is possible to obtain an attached color cathode ray tube.

[0024]

As described above, according to the present invention,
It is possible to provide the color cathode ray tube with the deflection yoke in which the leakage magnetic field in the color cathode ray tube is reduced without increasing the deflection current without using another component.

[Brief description of drawings]

FIG. 1 is a side view of a main part of a deflection unit for explaining an embodiment of a color cathode ray tube with a deflection yoke of the present invention.

FIG. 2 is an explanatory diagram of a wound state of the loop coil in FIG.

FIG. 3 is a side view of a deflection unit for explaining an embodiment of the present invention in detail.

FIG. 4 is a side sectional view for schematically explaining a structural example of a color cathode ray tube with a deflection yoke in which a color cathode ray tube is equipped with a deflection unit.

FIG. 5 is an explanatory diagram of a configuration example of a deflection unit that is packaged in a color cathode ray tube and an example of a generation pattern of an unnecessary magnetic field that is generated outside the vacuum envelope.

FIG. 6 is an explanatory diagram of a configuration example of a deflection unit showing an example of a conventional technique for reducing a leakage magnetic field.

[Explanation of symbols]

1 ... Panel part, 2 ... Neck part, 3 ...
Funnel part, 4 ... Phosphor screen, 5 ... Shadow mask structure, 6 ... Shadow mask, 7 ... Support frame, 8 ... Suspension spring, 9 ...
・ Stud pin, 10 ・ ・ ・ ・ Magnetic shield, 11 ・ ・
..Electron gun, 12 ... Magnet assembly, 13A
... Horizontal deflection coil, 13B ... Vertical deflection coil, 14 ... Explosion-proof band, 15 ... Deflection unit, 16 ... Deflection yoke, 17 ... Stem socket, 18 ... ... Loop coil, 19 ... Deflection current supply line, 20 ... Connector, 21 ... Separator, 22 ... Rotation correction coil, 23 ... Cancel coil.

Claims (4)

[Claims] 1. A vacuum envelope comprising a panel section having a phosphor screen forming a screen, a neck section accommodating an in-line electron gun for emitting an electron beam, and a funnel section connecting the panel section and the neck section. And a deflection yoke having a deflection coil which covers the neck portion and the funnel portion and which deflects the electron beam in two directions, horizontal and vertical, and a trajectory of the electron beam to correct a display screen on a phosphor screen. A deflection unit having a magnet assembly for optimizing color purity and convergence is provided, and a deflection current supply line for supplying a deflection current to a deflection coil forming the deflection yoke is provided outside the vacuum in an exterior region of the deflection unit. A loop coil for generating a canceling magnetic field that reduces the leakage magnetic field that is wound around the envelope and blows from the deflection coil to the outside of the deflection yoke. Color cathode-ray tube with a deflection yoke which is characterized in that the Le. 2. A color cathode ray tube with a deflection yoke, wherein the loop coil is wound around the neck portion. 3. The deflection coil comprises a horizontal deflection coil and a vertical deflection coil laminated via a separator, and the loop coil is wound around the neck side of the separator. Color cathode ray tube with deflection yoke. 4. The loop coil is a part of a deflection current supply line of the horizontal deflection coil.
3. A color cathode ray tube with a deflection yoke according to any one of 3 to 3.