JPH09259790A - Deflection yoke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deflection yoke by which various convergence errors, raster distortion or the like can be corrected and a convergence characteristic or the like can be improved with simple constitution by symmetrically forming recessed parts or projecting parts inside of cores. SOLUTION: In cores 30A and 30B, projecting parts A are formed in a symmetrical position to a virtual horizontal plane containing the tube axis of a cathode-ray tube, and are formed in a symmetrical shape to a plane vertical to this plane. The projecting parts A are extendedly formed in this circumferential direction so that a cross section becomes the same shape in the circumferential direction of the cores 30A and 30B. In this way, in the vicinity where the projecting parts A are formed, magnetic resistance of a magnetic circuit is reduced by the extent that a thickness of the cores 30A and 30B becomes thick. Therefore, magnetic flux density of a deflecting magnetic field can be improved in the vicinity of the projecting parts A, and the magnetic field distribution of the deflecting magnetic field can be locally corrected in a pin shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke, in which concave portions or convex portions are formed symmetrically inside a core to improve convergence characteristics and the like with a simple structure.

[0002]

2. Description of the Related Art Conventionally, in a deflection yoke, a vertical coil is wound in a saddle type or a toroidal type, and a vertical and horizontal coils form a deflection magnetic field that traverses the vicinity of the neck of a cathode ray tube vertically and horizontally. Has been done.

That is, FIG. 11 is a perspective view showing a schematic structure of this deflection yoke. In the deflection yoke 1, a pair of horizontal coils and a vertical coil are vertically and horizontally symmetrical with respect to the tube axis Z of the cathode ray tube. The coil is arranged, and further, the substantially conical cylindrical core 2 is arranged so as to surround the neck of the cathode ray tube. As a result, in the deflection yoke 1, the horizontal deflection magnetic field formed by the horizontal coil vertically traverses the neck of the cathode ray tube, and the horizontal deflection magnetic field deflects the electron beam left and right. Similarly, the deflection yoke 1 vertically deflects the electron beam by the vertical deflection magnetic field formed by the vertical coil, adjusts the magnetic field distribution of the deflection magnetic field formed by the horizontal deflection magnetic field and the vertical deflection magnetic field, and converges the convergence characteristic. , Raster distortion, etc. are corrected.

That is, as shown in FIG. 12, in a deflection yoke 6 for winding a vertical coil in a saddle shape, a coil bobbin is integrally formed with a die in advance in a winding step.
The horizontal coil is wound in a saddle shape. Further, the vertical coil V is wound in the same manner. The deflection yoke 6 is held integrally with the coil bobbin so that a pair of horizontal coils are opposed to each other, and subsequently, the deflection yoke 6 is surrounded by the coil coil so as to surround the outside of the horizontal coil.
A pair of vertical coils V are arranged, and the vertical coils V
The core 2 is arranged so as to surround the.

Further, in the deflection yoke 6 of this type, after the front cover 7 and the back cover 8 are mounted, the magnet 9 for adjusting the purity and the band 10 are mounted. At this time, in the deflection yoke 6, a ring-shaped plate-like member 11 having a partial protrusion on the funnel side is arranged on the outer periphery of the core 2, and the magnetic field distribution of the deflection magnetic field determined by the winding distribution of the horizontal coil and the vertical coil is set. The plate-shaped member 11 is used for correction. If necessary, an auxiliary coil 12 is attached to the back cover 8, and this auxiliary coil 12 also corrects the magnetic field distribution of the deflection magnetic field. Further, when the required convergence characteristics or the like cannot be obtained even by these means, the deflection yoke 6 is provided with a magnetic piece made of a magnetic material such as ferrite.
Paste on the inner surface of.

On the other hand, FIG. 13 shows a deflection yoke in which a vertical coil is wound in a toroidal shape. The deflection yoke 16 has a horizontal coil formed in the same manner as the deflection yoke 6 described above. On the other hand, the vertical coil V is formed by directly winding the core 17. That is, as shown in FIG. 14, in the core 17, a substantially conical cylindrical shape is formed into a shape that is divided into two by a plane including the central axis.
Is formed by directly winding a magnet wire around each of the divided parts according to a predetermined winding distribution.

The deflection yoke 16 is held integrally with the coil bobbin so that a pair of horizontal coils face each other.
Then, a pair of cores 17 is arranged and a vertical coil V is arranged so as to surround the outside of the horizontal coil. Further, after the front cover 18 and the back cover 19 are attached, the adjusting magnet 9, the band 10 and the like are attached. At this time, in the deflection yoke 16, as in the case where the vertical coil is formed in the saddle shape, the ring-shaped plate-shaped member 1 may be formed if necessary.
1 (FIG. 12), the auxiliary coil 12 and the like are attached, and the magnetic piece distribution of the deflection magnetic field is corrected by magnetic pieces such as ferrite.

In this way, in the deflection yoke in which the magnetic field distribution of the deflection magnetic field is adjusted to set the convergence characteristics and the like, and in the deflection yoke in which the magnetic circuit of the deflection magnetic field is formed by the core, a desired deflection sensitivity is secured. The height a of the core 17 is selected. Further, as shown in FIG. 15, the cathode ray tube 2
The shapes of the horizontal coil H, the vertical coil V, and the core 17 are selected so that the horizontal coil H, the vertical coil V, and the core 17 can be arranged as close as possible to the neck of No. 1, thereby improving the deflection sensitivity. It is done like this. Therefore, in the core 17, the inner surface of the cathode ray tube 21 has a shape similar to that of the funnel outer shape.

[0009]

By the way, when the magnetic field distribution of the deflection magnetic field is corrected by a magnetic piece such as ferrite as in the conventional deflection yoke, the work of attaching this magnetic material is necessary, and the deflection is correspondingly required. There is a problem that the number of manufacturing steps of the yoke increases. There is also a problem that the magnetic piece itself vibrates due to the deflection magnetic field, and the vibration sound is perceived to give an unpleasant feeling.

Further, in the correction method of attaching the magnetic piece, the magnetic flux density is locally increased to correct the magnetic field distribution, and the deflection magnetic field can be corrected to a pin-shaped magnetic field distribution, but the opposite is true. There is a problem that it cannot be corrected in the barrel shape.

The present invention has been made in consideration of the above points, and it is an object of the present invention to propose a deflection yoke which can solve these problems all at once and obtain desired convergence characteristics and the like.

[0012]

In order to solve the above problems, in the present invention, the inner surface of the core is axisymmetric with respect to the tube axis of the cathode ray tube, or with respect to a horizontal plane or a vertical plane including the tube axis. Symmetrically, the concave portions or convex portions are locally formed.

The locally formed protrusions reduce the magnetic resistance of the magnetic circuit and increase the magnetic flux density in the vicinity. Further, the locally formed recesses increase the magnetic resistance and reduce the magnetic flux density in the vicinity. Thereby, if necessary, the concave or convex portions can be formed symmetrically to correct the deflection magnetic field in the pin-shaped direction or the barrel-shaped direction.

[0014]

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

(1) First Embodiment FIG. 1 shows a deflection yoke according to a first embodiment of the present invention, in which a cross section of a core applied to the deflection yoke (FIG. 1).
(A)), plane (FIG. 1B) and side (FIG. 1C)
FIG. In the deflection yoke according to this embodiment, magnet wires are directly wound around the cores 30A and 30B to form a vertical coil having a toroidal shape. In FIG. 1, Φ indicates the direction of the main deflection magnetic field.

That is, each of the cores 30A and 30B is formed into a shape in which a substantially conical cylindrical shape is divided into two parts by a plane including the central axis, and an elongated convex portion A is formed at a substantially central portion in the pipe axis direction.
Is formed. Here, in the cores 30A and 30B,
The convex portion A is formed at a symmetrical position with respect to an imaginary horizontal plane including the tube axis of the cathode ray tube (that is, a surface that separates the cores 30A and 30B), and a surface perpendicular to this plane (that is, the cathode ray tube). Of the imaginary vertical plane including the tube axis) is formed symmetrically.

Further, the convex portion A has cores 30A and 30A.
It is formed so as to extend in the circumferential direction of B so that the cross section has the same shape in the circumferential direction. The width A of the convex portion A in the direction along the tube axis is the height a of the cores 30A and 30B.
The length is selected to be sufficiently short with respect to (in this case, the length of the vertical coil) so that the overall magnetic field distribution of the vertical deflection magnetic field is not significantly affected. There is. Further, in the convex portion A, a corner portion or the like is formed with a predetermined curvature, if necessary, so that a damage accident of the mold when the cores 30A and 30B are manufactured can be prevented.

As a result, in the cores 30A and 30B, the overall magnetic field distribution of the vertical deflection magnetic field does not have a great influence, but in the vicinity where the convex portion A is formed in this manner, the cores 30A and 30B are not affected. As the wall thickness increases, the magnetic resistance of the magnetic circuit decreases. Therefore, the magnetic flux density of the deflection magnetic field can be improved in the vicinity of the convex portion A, and the magnetic field distribution of the deflection magnetic field can be locally corrected to the pin shape.

Specifically, when the convex portion A is formed and the magnetic field distribution of the deflection magnetic field is corrected as in this embodiment, the circumferential length L and position of the convex portion A are used as parameters. By selecting the types of misconvergence and raster distortion to be corrected, and then selecting the width W of the convex portion A to determine the correction amount, the convergence characteristics and the like of the raster image can be set to desired characteristics. it can.

That is, as in this embodiment, the formation of the convex portion A is selected symmetrically with respect to an imaginary vertical plane including the tube axis of the cathode ray tube, and the convex portion A is symmetrical to the horizontal plane. When A is formed, as shown in FIG. 2, it is possible to correct misconvergence intersecting in the left-right direction (which is so-called intermediate cross-type vertical misconvergence) at the intermediate portions in the vertical direction from the center of the screen. Further, as shown in FIG. 3, when horizontal lines are displayed above and below the raster image, it is possible to correct raster distortion (so-called tongue-shaped raster distortion) in which the horizontal lines are undulated symmetrically in the vertical direction.

In the above-described structure, in the deflection yoke, the vertical deflection magnetic field is generated by the vertical coil directly wound on the cores 30A and 30B, and the vertical deflection magnetic field crosses the neck of the cathode ray tube, and then the core 30A. And around 30B for about half a turn to return to the original vertical coil. Further, a horizontal deflection magnetic field is generated from the horizontal coil wound in the saddle shape, and after the horizontal deflection magnetic field crosses the neck of the cathode ray tube, the cores 30A and 30B are circulated about half a round and returned to the original horizontal coil.

At this time, in the convex portions A of the cores 30A and 30B, the magnetic resistance is reduced, the magnetic flux density is increased accordingly, and the magnetic field distribution is corrected in the pin-shaped direction. As a result, in the deflection magnetic field, the magnetic field distribution is locally corrected in the vicinity of the center of the deflection magnetic field in the direction of the tube axis Z in which the convex portion A is formed, and the intermediate cross type vertical misconvergence and the skip-shaped raster distortion are corrected. can do.

According to the above configuration, the cores 30A and 30
By forming a convex portion inside B in a symmetrical manner with respect to a horizontal plane including the tube axis Z, the magnetic field distribution is locally corrected by simply winding on the cores 30A and 30B, and the intermediate portion intersecting type is formed. Vertical misconvergence and tonbin-shaped raster distortion can be corrected. Therefore, the work of attaching the magnetic piece or the like can be omitted, the manufacturing process of the deflection yoke can be simplified accordingly, and the generation of unpleasant vibration noise can be effectively avoided.

(2) Second Embodiment FIG. 4 is a diagram showing a core applied to a deflection yoke according to a second embodiment of the present invention, in comparison with FIG. In this deflection yoke, as in the first embodiment,
A magnet wire is directly wound around the cores 31A and 31B to form a vertical coil having a toroidal shape.

That is, in the cores 31A and 31B, groove-shaped recesses B are formed on the funnel side in the tube axis direction, at four locations substantially corresponding to the corners of the raster image. Here, in the cores 31A and 31B, the concave portion B is formed at a position symmetrical with respect to an imaginary horizontal plane including the tube axis of the cathode ray tube, and at a predetermined angle in the circumferential direction about a plane perpendicular to the horizontal plane. They are spaced apart from each other and are formed symmetrically with respect to this vertical plane.

Further, the recess B has cores 31A and 31A.
It is formed so as to extend in the circumferential direction so that the cross section has the same shape in the circumferential direction of B, and the width W in the direction along the tube axis is sufficient for the height a of the cores 31A and 31B. Short length is selected. Further, in the recess B, corner portions and the like are formed with a predetermined curvature as necessary, so that damage to the mold or the like when manufacturing the cores 31A and 31B can be prevented.

As a result, in the cores 31A and 31B, the overall magnetic field distribution of the vertical deflection magnetic field does not have a great influence, but the core 3 in the vicinity of the recess B is affected.
As the thickness of 1A and 31B is reduced, the magnetic resistance of the magnetic circuit increases. Therefore, the magnetic flux density of the deflection magnetic field can be reduced in the vicinity of the recess B by that much,
The magnetic field distribution of the deflection magnetic field can be locally corrected to a barrel shape.

Specifically, in the case where the concave portions B are formed at four positions substantially corresponding to the corners of the raster image on the funnel side to correct the magnetic field distribution of the deflection magnetic field as in this embodiment, the first embodiment is performed. Similar to the form, the length L and position of the recess B in the circumferential direction are used as parameters to select the type of misconvergence and raster distortion to be corrected, and subsequently the width W of the recess B is selected to correct the correction amount. By determining, the convergence characteristics and the like of the raster image can be set to desired characteristics.

That is, as in this embodiment, the concave portions B are formed at four places substantially corresponding to the corners of the raster image on the funnel side, and as shown in FIG. Convergence (which is so-called corner crossing vertical misconvergence) can be mainly corrected.

According to the configuration shown in FIG. 4, inside the cores 31A and 31B, symmetrically with respect to the horizontal plane including the tube axis Z,
Funnel side, almost corresponding to the corner of raster image 4
By forming the recess B at the location, the magnetic field distribution can be locally corrected by simply winding around the cores 31A and 31B and the corner crossing vertical misconvergence can be corrected. Therefore, the work of attaching the magnetic piece or the like can be omitted, the manufacturing process of the deflection yoke can be simplified accordingly, and the generation of unpleasant vibration noise can be effectively avoided. In addition to these, the deflection magnetic field can be corrected into a barrel shape.

(3) Third Embodiment As shown in FIG. 6, in this embodiment, a cathode ray is provided in the vicinity of the surface separating the cores 32A and 32B on the funnel side and asymmetrically with respect to a horizontal plane and a vertical plane. Two groove-shaped concave portions B are formed symmetrically with respect to the tube axis of the tube. The shape of the recess B is selected similarly to the above-described second embodiment.

As a result, in the deflection yoke, as shown in FIG. 7, the asymmetric component of the deflection magnetic field in the vertical and horizontal directions with respect to the electron beam is corrected, and the entire raster image is curved in the horizontal direction and in the same direction. Increasing or decreasing misconvergence (ie consisting of bow-shaped vertical misconvergence) can be mainly compensated.

According to the configuration shown in FIG. 8, the inner side of the cores 32A and 32B, the vicinity of the plane separating the cores 32A and 32B, asymmetrically with respect to the horizontal plane and the vertical plane, with respect to the tube axis of the cathode ray tube. By forming the two concave portions B symmetrically about the axis, the arcuate vertical misconvergence can be mainly corrected by simply winding the windings around the cores 33A and 33B. Therefore, the same effect as in the second embodiment can be obtained by correcting the bow-shaped vertical misconvergence.

(4) Fourth Embodiment As shown in FIG. 8, in this embodiment, a groove-shaped concave portion B is formed at the position where the convex portion A according to the first embodiment is formed. The shape of the recess B is selected similarly to the above-described second embodiment.

As a result, the deflection yoke can correct the intermediate cross type vertical misconvergence and the skip type raster distortion described above with reference to FIG. 1 in the direction opposite to that of the first embodiment. The same effect as that of the second embodiment can be obtained by correcting the shape vertical misconvergence and the skip-shaped raster distortion.

(5) Fifth Embodiment As shown in FIG. 9, in the cores 34A and 34B according to this embodiment, the recess B is also formed for the second to third embodiments described above. Further, the concave portion B is separately formed on the neck side and the central portion.

As in this embodiment, if necessary,
If the recess B is formed in each part, the magnetic flux density can be reduced in each part, and various convergence characteristics and the like can be corrected in addition to the effects of the second to third embodiments described above.

(6) Other Embodiments In the above second to fifth embodiments, the case where the recess is formed inside the core has been described, but the present invention is not limited to this, and the recess is not limited to this. May be formed deeper and penetrate to the outside like the cores 35A and 35B shown in FIG. 10, for example. By doing so, the deflection magnetic field can be corrected in a barrel shape even more strongly.

In the above-mentioned embodiment, the case where the vertical coil is formed in a toroidal shape has been described.
The present invention is not limited to this, and can be applied to the case of forming a saddle shape.

[0040]

As described above, according to the present invention, the recesses or protrusions are formed symmetrically inside the core, and the position and size of the recesses or protrusions are selected to obtain various misconvergence. It is possible to correct the raster distortion and the like, which makes it possible to obtain a deflection yoke having a simple configuration and capable of improving the convergence characteristics and the like.

[Brief description of drawings]

FIG. 1 is a diagram showing a core applied to a deflection yoke according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing misconvergence that can be corrected by the deflection yoke of FIG.

FIG. 3 is a schematic diagram showing raster distortion that can be corrected by the deflection yoke of FIG.

FIG. 4 is a diagram showing a core applied to a deflection yoke according to a second embodiment of the present invention.

5 is a schematic diagram showing misconvergence that can be corrected by the deflection yoke of FIG.

FIG. 6 is a diagram showing a core applied to a deflection yoke according to a third embodiment of the present invention.

7 is a schematic diagram showing misconvergence that can be corrected by the deflection yoke of FIG.

FIG. 8 is a diagram showing a core applied to a deflection yoke according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing a core applied to a deflection yoke according to a fifth embodiment of the present invention.

FIG. 10 is a diagram showing a core applied to a deflection yoke according to another embodiment of the present invention.

FIG. 11 is a perspective view showing a schematic configuration of a deflection yoke.

FIG. 12 is a side view showing a conventional deflection yoke in which a vertical coil is formed in a saddle shape.

FIG. 13 is a side view showing a conventional deflection yoke in which a vertical coil has a toroidal shape.

FIG. 14 is a side view showing a core applied to a conventional deflection yoke.

FIG. 15 is a cross-sectional view showing a state in which the deflection yoke of FIG. 13 is attached to a cathode ray tube.

[Explanation of symbols]

1, 6, 16 ... Deflection yoke, 2, 17, 30A, 30
B, 31A, 31B, 32A, 32B, 33A, 33
B, 34A, 34B, 35A, 35B ... Core, A ...
Convex part, B, C ... Recessed part, V ... Vertical coil

Claims (2)

[Claims] 1. A deflection yoke for forming a magnetic circuit by a core having a substantially conical cylindrical shape and applying a deflection magnetic field to a cathode ray tube, wherein an inner surface of the core is axially symmetric with respect to a tube axis of the cathode ray tube. Alternatively, the deflection yoke is characterized in that concave portions or convex portions are locally formed symmetrically with respect to a horizontal plane or a vertical plane including the tube axis. 2. The deflection yoke according to claim 1, wherein the concave portion penetrates to an outer side surface of the core.