JPH06223743A - Deflection yoke - Google Patents

Abstract

PURPOSE:To reduce the number of process to correct a color slippage of a cathode-ray tube, and to standardize and automate the color correcting work, by providing plural magnet pieces for color slippage correction rotatable to the periphery of the large diameter part of a trampet-shaped bobbin. CONSTITUTION:In a deflection yoke 20 of a cathode-ray tube in which a horizontal coil 3 and a vertical coil (not shown in the figure) are wound on a trampet-shaped bobbin 1, plural magnet pieces 8 for color slippage correction are provided rotatable to the periphery of the large diameter part 6 of the trampet-shaped bobbin 1. In the assembly work of this deflection yoke 20, a worker confirms the convergence propery particular to the cathode-ray tube by observing the color slippage and the color unevenness of the image on the cathode-ray tube, and when it is necessary to correct, necessary number of magnet pieces 8 are rotated with a driver while observing the cathode- ray tube. And, at the same time with this operation or independently, necessary number of magnet installing tools 7 are moved on the periphery of the large diameter part 6 of the bobbin 1, so as to change and fix the positions of the magnet pieces 8. Consequently, the positions and the directions of the magnet pieces 8 on the bobbin 1 to make the convergence property to the best condition can be determined rapidly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke for a cathode ray tube.

[0002]

2. Description of the Related Art In a cathode ray tube, that is, a cathode ray tube of a television receiver or the like, an electron beam emitted from an electron gun built in a neck at a rear portion of the cathode ray tube is deflected vertically and horizontally so that an image is properly sent to every corner of the screen. A deflection yoke is attached to the outside of the cathode ray tube at the boundary between the neck and the funnel. This deflection yoke is usually
A horizontal deflection coil is wound in a saddle shape on the inside of a bobbin expanded in a trumpet shape, and a vertical deflection coil is wound in a saddle shape on the outside of the bobbin.

On a color television, color irregularities and color shifts often occur which make it difficult to see the edges of an image. This is caused by the poor superposition of the three color images. To correct this, the three electron beams are concentrated in one on the screen (convergence) regardless of where they are deflected on the screen. ), The electron beam must be deflected to adjust the convergence characteristics. As a method of adjusting the convergence characteristic, there is a method of attaching an image correction member such as a ferrite sheet to the bobbin of the deflection yoke or the deflection coil.

Conventionally, during assembly work of the deflection yoke, an operator observes the Braun tube to determine whether or not it is necessary to attach the ferrite sheet to the deflection yoke, and further decides the attachment location. At that time, repeat trial and error, remember the position that seems to be appropriate, remove the deflection yoke, attach the ferrite sheet if the position is inside the deflection yoke, and stick the silicon steel plate if it is outside the deflection yoke. The convergence characteristics are adjusted by attaching the image correction plate made in. This work is repeated many times. An image correction member such as a ferrite sheet or an image correction plate made of a silicon steel plate has a function of changing a magnetic field by absorbing a magnetic flux of an electron beam. Ferrite refers to a ceramic whose main component is iron oxide and whose magnetization is hard to disappear.

[0005]

However, in the above-mentioned conventional method, there is a drawback that the tendency of the convergence characteristic changes from worker to worker and the convergence characteristic varies, resulting in a difference in the criterion for determining the convergence characteristic. Also,
There is a drawback in that the adjustment time of the convergence characteristic varies depending on the skill level of the operator. Therefore, there is a drawback that the adjustment work cannot be standardized and automated.

Further, since there is no standard for the position where the image correction member such as a ferrite sheet is attached to the deflection yoke, the image is attached depending on the feeling, and therefore it cannot always be attached at the proper position. Therefore, this work has to be repeated many times, and there is a drawback that the number of man-hours for actual work increases.

The present invention has been made in view of the above points, and has means for reducing the number of steps for correcting the color misregistration of the cathode ray tube, and for standardizing and automating the color misregistration correction work. The purpose is to provide a deflection yoke.

[0008]

In order to solve the above-mentioned problems, the present invention provides a deflection yoke of a cathode ray tube in which a horizontal deflection coil and a vertical deflection coil are wound around a trumpet-shaped bobbin, and a large-diameter portion of the trumpet-shaped bobbin is provided. A plurality of color misregistration correction magnet pieces are rotatably arranged on the outer circumference.

Further, the present invention is characterized in that the magnet piece is a columnar ferrite or a columnar plastic magnet.

Further, the present invention is characterized in that the magnet pieces are arranged so as to be movable in the circumferential direction in the large diameter portion of the trumpet-shaped bobbin.

[0011]

By rotating or rotating some of a plurality of magnet pieces attached to the outer circumference of the large-diameter portion of the trumpet-shaped bobbin of the deflection yoke, at the same time as or separately from these magnet pieces, the magnet pieces are By moving an object in the circumferential direction of the large-diameter portion of the trumpet-shaped bobbin, the magnetizing action of these magnet pieces as a whole is changed, and the convergence correction of the deflection yoke is performed to correct the color shift of the cathode ray tube.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view of the deflection yoke of the present invention viewed from the large diameter side, and FIG. 2 is a side view of the deflection yoke of the present invention.

In a cathode ray tube or cathode ray tube of a television receiver or the like, a deflection yoke 20 for vertically and horizontally deflecting an electron beam emitted from an electron gun built in a neck at a rear portion thereof is provided at a boundary between the neck and the funnel. Part, it is attached to the outer circumference of the cathode ray tube.

In this deflection yoke 20, a horizontal deflection coil 3 is usually wound in a saddle shape on the inside of a resin bobbin 1 formed in a trumpet shape, and a vertical deflection coil 2 is also saddle-shaped on the outside of the bobbin 1. It is wound. A two-divided core 4 is attached so as to enclose the vertical deflection coil 2. The bobbin 1 has a small diameter portion 5 near the neck portion of the cathode ray tube and a large diameter portion 6 near the screen.

Eight magnet fixtures 7 are attached to the outer peripheral surface of the large diameter portion 6 of the bobbin 1 of the deflection yoke 20 at equal intervals of 45 degrees.

FIG. 3 is a perspective view of the magnet fixture 7.

The magnet fitting 7 is provided with a holding portion 9 for holding the magnet piece 8 and mounting portions 10 projecting from both ends of the holding portion 9, and is made of metal, plastic or the like. The magnet mounting tool 7 is such that a screw 11 is passed through an elongated hole 12 formed in the mounting portion 10, and this is mounted on the bobbin 1.
It is screwed and fixed in the screw hole 13 provided on the outer peripheral surface of the large diameter portion 6. Note that this fixing method may use screwing and welding together. In this way, the magnet fixture 7 can be moved on the outer peripheral surface of the large diameter portion 6 by the length of the elongated hole 12, for example, the central angle ± 10 degrees.

The magnet piece 8 is used for correcting the color shift of the cathode ray tube, and is a columnar magnet having an N pole and an S pole, such as a ferrite or plastic magnet, and a holding portion 9 of the magnet fixture 7. It can be rotated in the direction of arrow A, that is, it can be rotated. A groove 14 into which a rotating tool such as a driver is inserted for this turning operation is formed on the end surface.

The deflection yoke 20 of the present invention described above is used as follows.

At the time of assembling the deflection yoke 10, the operator observes the color shift and color unevenness of the image of the cathode ray tube to confirm the convergence characteristic peculiar to the cathode ray tube, and determines whether or not it is necessary to correct it. When the correction is necessary, the required number of magnet pieces 8 are rotated by the driver while looking at the screen of the cathode ray tube. At the same time as this operation,
Alternatively, separately from this operation, by moving a required number of magnet attachments 7 on the outer peripheral surface of the large diameter portion 6 of the bobbin 1, the position of the magnet piece 8 is changed and fixed. As described above, by performing each of these operations while observing the image of the cathode ray tube, the bobbin 1 having the best convergence characteristics.
The position / direction of each of the upper magnet pieces 8 can be quickly determined. In addition, the series of operations is easily automated and the work is standardized, so that even an unskilled person can easily perform the operation.

In the above embodiment, eight cylindrical magnet pieces 8 are used.
Are arranged on the outer peripheral surface of the large diameter portion 6 of the bobbin 1. The number, material, magnetic flux density, rotating number, non-rotating number, the mounting position of the bobbin 1 on the large diameter portion 6, and the mounting method. , The ratio of the number of fixed positions and the number of moved positions can be designed appropriately. For example, an odd-numbered one of the eight magnet pieces 8 may be a fixed type and an even-numbered one may be a movable type, and the magnet fixture 7 may be a magnet mount holder of another type. You can also The magnet piece 8 may have any shape, but the cylindrical shape as described above is preferable in operation.

[0023]

As described above, in the deflection yoke of the present invention, a plurality of color misregistration correction magnet pieces are rotatably provided on the outer circumference of the trumpet-shaped bobbin on the large diameter side, and the large diameter of the trumpet-shaped bobbin is used. Since it is attached so that it can move in the circumferential direction of the part,
The following excellent effects can be obtained. (1) The operator himself can correct the color misregistration and color unevenness by adjusting the convergence characteristics of the CRT while viewing the screen of the CRT. (2) The number of man-hours for correcting color misregistration and color unevenness of the cathode ray tube can be reduced to about half. (3) It is possible to automatically correct the color shift and color unevenness of the cathode ray tube. (4) Color misregistration and color unevenness can be corrected even with an arbitrary combination of a cathode ray tube and a deflection yoke.

[Brief description of drawings]

FIG. 1 is a front view of a deflection yoke of the present invention.

FIG. 2 is a side view of the deflection yoke of the present invention.

FIG. 3 is a perspective view of a magnet attachment used in the deflection yoke of the present invention.

[Explanation of symbols]

 1 Bobbin 2 Vertical Deflection Coil 3 Horizontal Deflection Coil 6 Large Diameter Part 7 Magnet Fixture 8 Magnet Piece 20 Deflection Yoke

Claims (4)

[Claims] 1. A deflection yoke of a cathode ray tube comprising a trumpet-shaped bobbin wound with a horizontal deflection coil and a vertical deflection coil,
A deflection yoke, wherein a plurality of color misregistration correction magnet pieces are rotatably arranged on the outer periphery of the large-diameter portion of the trumpet-shaped bobbin. 2. The deflection yoke according to claim 1, wherein the magnet piece is a cylindrical ferrite. 3. The deflection yoke according to claim 1, wherein the magnet piece is a cylindrical plastic magnet. 4. The deflection yoke according to claim 1, wherein the magnet piece is arranged so as to be movable in a large diameter portion of the trumpet-shaped bobbin in a circumferential direction.