JPS63289748A - Deflecting yoke for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To obtain an image with no distortion by installing plate-shaped magnets having a boss at the top and bottom of the front opening of a coil bobbin. CONSTITUTION:Magnets 9, 10 are installed at the top and bottom of the front opening 6a of a coil bobbin constituting a deflecting yoke. They consist of long plates 9a, 10a and short bosses 9b, 10b, respectively, wherein the bosses 9b, 10b protrude in the center of the plates 9a, 10a. A raster 15 generated by the winding form of horizontal deflecting coils 2, 3 and eventual misconvergence is corrected with a raster 16 by the magnetic field produced by the plates 9a, 10a. The central recess of the raster 16 is corrected by the magnetic field produced by the bosses 9b, 10b into a straight raster 17 without distortion. Thus an image with no distortion is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Utilization Tube> The present invention relates to a deflection yoke mounted on a cathode ray tube of a color television receiver.

<Prior Art> As is well known, a horizontal deflection coil is used as a deflection device that is mounted on a color picture tube having six electron guns arranged in-line and deflects the beam generated by each electron gun. Theoretically, misconvergence can be reduced to zero by configuring the deflection field as a whole to have a pincushion-shaped deflection magnetic field, and by configuring the vertical deflection coil to have a barrel-type deflection magnetic field.

On the other hand, in recent years, in wide-angle CRTs such as 100° to 110° deflection, the horizontal deflection coil that forms part of the deflection yoke mounted on the CRT is wound in a hollow shape, and the winding angle is As a result, as shown in Figure 5, there is bin distortion that remains at the top and bottom of the screen due to misconvergence, and the winding of the horizontal deflection coil. Raster distortion 20 is generated by combining waveform distortion (Gull Wing distortion) due to the round shape.

In the conventional deflection yoke, in order to correct the raster distortion 20 shown in FIG. 5, as shown in FIG.
A long-dimension rod-shaped magnet 62 and a short-dimension rod-shaped magnet 33 are installed vertically on the outer periphery of the
The pin distortion of 0 is corrected, and the wavy type of the reraster distortion 20 is corrected by the short magnet 33, and finally, as shown in FIG. The result was a screen with

<Problems to be Solved by the Invention> However, in such a conventional configuration, in order to correct raster distortion on the screen, a long magnet and a short magnet are combined at predetermined positions of the deflection yoke. However, there are problems in that the number of magnets increases, which increases costs, and the number of man-hours required to attach the magnets increases, deteriorating workability.

Means for Solving the Problems> The present invention has been made to solve the above problems.
A core, a pair of saddle-shaped horizontal deflection coils wound along the core, and a coil bobbin arranged on the inner surface of the core to maintain insulation between both coils and to define the positions of both coils. In the deflection yoke for a color cathode ray tube, the winding angle at the opening of the horizontal deflection coil is smaller than the winding angle at the neck part, and a raster is formed in a shape having a recess at least in the center at the top and bottom of the screen of the cathode ray tube. , plate-shaped magnets each having protrusions at the upper and lower parts of the front opening of the coil bobbin for correcting the dent in the central part.
It is made by installing individual parts.

By using a plate-shaped magnet with protrusions, the main body of the magnet (plate-shaped part) corrects the pin distortion of the raster distortion on the screen, and the protrusions of the magnet correct the raster distortion of the raster distortion. The dent in the center (Gu 11 Wi ng distortion) is corrected to obtain a distortion-free raster.

<Embodiment> Hereinafter, an embodiment of the deflection yoke for a color cathode ray tube according to the present invention will be described in detail with reference to the drawings. Figure 1.

In FIG. 2, reference numeral 1 denotes an annular core, on the inner surface of which is wound a pair of saddle-shaped horizontal deflection coils 2.3, and on the outer periphery is a pair of toroidal-shaped vertical deflection coils 4.
is wrapped. 6 is arranged on the inner surface of the core 1 to maintain insulation between the horizontal deflection coil 2.3 and the vertical deflection coil 4.5;
In addition, it is a coil bobbin that defines the position of each coil 2°6.4.5.
It is attached and fixed onto the neck portion 8a of the in-line type color cathode ray tube 8. The horizontal deflection coil 2.3 constituting the deflection yoke 7 is wound so that the winding angle θ at the opening is smaller than the winding angle θ at the neck. , 4th
As shown by the solid line in Figure (A), a raster 15 having a depression in the center is generated. On the other hand, in the upper and lower parts of the front opening 6a of the coil bobbin 6 that constitutes the deflection yoke 7,
One magnet) 9.10 is attached to each. The magnet 9 (10) is made of ferrite, and as shown in FIG.
9a (1 (1a)) and a short protrusion 9b (10b) protruding from the center of the fill bobbin 6.
Mounted on the outer circumference of the bottom.

In the deflection yoke for color cathode ray tubes having such a configuration,
The raster 15 shown by the solid line in FIG. 4(A), which is caused by the relationship between the winding shape of the horizontal deflection coil 2.3 and misconvergence, is the elongated plate-like portion 9a of the magnet 9°10,
The magnetic field generated by magnet 9.10a corrects the raster 16 shown by the broken line in FIG. 4(A).
Due to the magnetic field generated by the short protrusions 9b and 10b, the dent in the center of the raster 16 shown by the broken line in FIG. The raster 17 is corrected to a straight line without any distortion, and as a result, a screen without distortion can be obtained.

In one embodiment of the deflection yoke of the present invention, the shape of the magnets installed above and below the front opening of the coil bobbin of the deflection yoke is described as having a protrusion only in the center. However, depending on the state of strain (for high-order strain), the number of protrusions may be increased to configure the magnet to have, for example, a substantially mountain-shaped cross section. Furthermore, in one embodiment of the deflection yoke of the present invention, only one magnet is attached to the upper and lower parts of the coil bobbin of the deflection yoke, but as shown by the broken line in FIG. It may also be configured by attaching a separate magnet (11.12) to the back of the opening 6a.
It is arbitrary to combine the magnets 9 and 10 having the protrusions 9b and 10b with other magnets, and the combination can be set in various ways depending on the form of raster distortion. Further, although ferrite has been described as the magnet material, the magnet may also be constructed using metal or molded products.

<Effects of the Invention> The deflection yoke of the present invention is as described above in detail,
Raster distortion on the screen is eliminated by the magnetic field generated by the magnet, and good screen characteristics can always be obtained. In addition, it is only necessary to attach two magnets to the top and bottom of the front opening of the coil bobbin of the deflection yoke, which reduces the number of magnets, reduces material costs, reduces man-hours, and improves workability. This is effective as a deflection yoke for wide-angle cathode ray tubes.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view of a deflection yoke according to an embodiment of the present invention mounted on a color cathode ray tube, FIG. 2 is a front view of the deflection yoke, and FIG. 3 is a perspective view of the magnet. Figure 4 is a pattern diagram showing the change in raster when the deflection yoke of the present invention is used. Figure (A) is at the intermediate stage of correction, Figure (B) is at the completion of compensation, and Figure 5 is at the time of completion of correction. A pattern diagram showing the raster distortion that occurs in a conventional wide-angle cathode ray tube. Figure 6 (A) is a front view of a conventional deflection yoke.
The same figure (B) is a side view of the main part of another conventional deflection yoke.
The figure is a raster pattern diagram when a conventional deflection yoke is used. 1...Core, 2,6...Horizontal deflection coil, 4.5...-
Vertical coil, 6-coil bobbin, 6a Coil bobbin front opening, 7... Deflection yoke, 8... Color cathode ray tube, 9.10... Magnet, 9b, 10b...
・Magnet protrusion・ Patent applicant Denki Acoustics Co., Ltd. Figure 2 Figure 4 Figure 6 (A) (B)

Claims (1)

[Claims] A core, a pair of saddle-shaped horizontal deflection coils wound along the core, a saddle-shaped or toroidal-shaped vertical deflection coil, and a pair of coils arranged on the inner surface of the core to maintain insulation between the two coils. , and a coil bobbin that defines the positions of both coils, the winding angle at the opening of the horizontal deflection coil is smaller than the winding angle at the neck part, and the winding angle at the opening of the horizontal deflection coil is smaller than the winding angle at the neck part, so that , each plate-shaped magnet is formed into a raster shape having a dent at least in the center, and has protrusions at the upper and lower parts of the front opening of the coil bobbin for correcting the dent in the center. Deflection yoke for color cathode ray tubes, characterized by the fact that it is equipped with individual parts.