JP2002025470A - Deflection yoke and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deflection yoke that is capable of correcting local misconvergence, without increasing the number of components and cost increase due to manufacturing labor. SOLUTION: The deflecting coil comprises a horizontal deflecting coil, which generates a horizontal deflecting field, a vertical deflecting coil which is wound into a saddle shape on the separator at the outside of the horizontal deflecting coil, and an auxiliary coil 22, which generates a magnetic field in a direction opposite to the horizontal deflecting field by the excited current that, is excited by the horizontal deflecting field by the horizontal deflecting coil and which is wound on a part of the separator 21 wounded with the vertical deflecting coil. According to this auxiliary coil, a local misconvergence is corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cathode ray tube (CRT).
More particularly, the present invention relates to a deflection yoke used for a display device such as a television receiver or a computer display using the same.

[0002]

2. Description of the Related Art Generally, in a display device using a cathode ray tube, an image is displayed on a screen by deflecting three electron beams emitted from an electron gun up, down, left, and right.
For deflection of the electron beam, a deflection yoke (DY) having a horizontal deflection coil and a vertical deflection coil is used. The horizontal deflection coil generates a horizontal deflection magnetic field that deflects the electron beam in the horizontal direction (horizontal direction), and the vertical deflection coil generates a vertical deflection magnetic field that deflects the electron beam in the vertical direction (vertical direction). It is.

In such a display device, the beam trajectories of the three electron beams emitted from the electron gun are controlled so as to converge on a phosphor screen formed on the inner surface of the panel of the cathode ray tube. However, a so-called convergence shift (hereinafter, misconvergence) may occur in which the three electron beams do not converge at one point due to an assembly error of the deflection yoke or the cathode ray tube.

There are various types of misconvergence occurrences, and various convergence correction devices have been proposed correspondingly. Most of the misconvergence appears with a certain regularity over the entire screen of the cathode ray tube, but in addition, for example, local misconvergence occurs only in one of the four corners of the screen. May be.

Conventionally, as a countermeasure, a sheet piece (for example, a soft ferrite sheet or the like) made of a magnetic material is attached to a deflecting coil, thereby weakening the deflecting magnetic field at the attached portion to correct local misconvergence. Techniques for doing so are known.

[0006]

However, in the technique for attaching a sheet piece as described above, it is necessary to produce a sheet piece in accordance with the form of misconvergence and to attach it to an appropriate position. It was not always a good idea because of the manufacturing effort.

Japanese Patent Laid-Open Publication No. Hei 10-188853 discloses a configuration of a deflection yoke in which a holder is interposed between a horizontal deflection coil and a vertical deflection coil to electrically insulate both deflection coils. A technique is disclosed in which an auxiliary coil is attached and a magnetic field in a direction opposite to a horizontal deflection magnetic field is formed by a current induced in the auxiliary coil to correct misconvergence. However, in this technique, since an auxiliary coil for convergence correction needs to be attached as a separate component, the manufacturing cost is significantly increased due to an increase in the number of components and manufacturing effort.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to reduce the local misconvergence without causing an increase in the number of parts and an increase in manufacturing cost due to manufacturing labor. Is to provide a deflection yoke that can correct the above.

[0009]

In a deflection yoke according to the present invention, a horizontal deflection coil for generating a horizontal deflection magnetic field, a vertical deflection coil wound saddle-shaped on a separator outside the horizontal deflection coil, A current is induced by a horizontal deflection magnetic field generated by a horizontal deflection coil, and a magnetic field in a direction opposite to the horizontal deflection magnetic field is generated by the induced current.
An auxiliary coil is wound around a predetermined portion of the separator on which the vertical deflection coil is wound. Further, the display device according to the present invention uses the deflection yoke having the above-described configuration.

In the deflection yoke and the display device using the same, when a current is induced in the auxiliary coil by the horizontal deflection magnetic field generated by the horizontal deflection coil, the auxiliary coil generates a magnetic field in a direction opposite to the horizontal deflection magnetic field. Therefore, the strength of the horizontal deflection magnetic field is weakened at a position corresponding to the winding position of the auxiliary coil. By winding the auxiliary coil having such a magnetic field effect around the common separator with the vertical deflection coil, local misconvergence is corrected without increasing the number of parts and hardly increasing the number of manufacturing steps. It becomes possible.

[0011]

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

FIG. 1 is a schematic perspective view showing an overall image of a cathode ray tube according to the present invention. As shown in the figure, the main body (glass bulb) of the cathode ray tube 10 includes a panel section 11, a funnel section 12, and a neck section 13. On the inner surface of the panel section 11, a phosphor screen (not shown) in which red, green, and blue phosphors are arranged in a pattern is formed. on the other hand,
An electron gun 1 serving as an electron beam emission source is provided in the neck portion 13.
4 are furnished. As the electron gun 14, for example, red,
An in-line type that emits three electron beams corresponding to each color of green and blue in an in-line manner is used. Also,
A deflection yoke 15 for deflecting the electron beam is mounted on a cone portion extending from the neck portion 13 to the funnel portion 14. The deflection yoke 51 is attached and adjusted so that the center axis of the yoke coincides with the center axis of the cathode ray tube 10.

The cathode ray tube 10 having the above-described structure includes a panel 11
Along with various accessories necessary for reproducing a color image (or a black-and-white image) on the inner fluorescent screen, it is incorporated into a casing (not shown) together with a display device such as a television receiver or a computer display. You.

FIG. 2 is a half sectional view showing the structure of the deflection yoke according to the present invention. As shown, the deflection yoke 15 includes a horizontal deflection coil 16, a vertical deflection coil 17, and a DY core 1.
8, the front cover 19 and the back cover 20 are provided.

The horizontal deflection coils 16 are arranged in pairs in the vertical axis direction (vertical direction) of the deflection yoke 15, and the vertical deflection coils 17 are paired in the horizontal axis direction (left / right direction) of the deflection yoke 15. Are located. Horizontal deflection coil 16
Generates a horizontal deflection magnetic field that deflects the electron beam in the horizontal axis direction by a sawtooth horizontal deflection current supplied from a horizontal deflection circuit (not shown). The vertical deflection coil 17 generates a vertical deflection magnetic field for deflecting the electron beam in the vertical axis direction by a sawtooth vertical deflection current supplied from a vertical deflection circuit (not shown).

The DY core 18 is formed in a substantially conical cylindrical shape with a magnetic material such as ferrite, and is arranged so as to cover the horizontal deflection coil 16 and the vertical deflection coil 17 described above. The DY core 18 is provided with the horizontal deflection coil 1.
6 and the function of increasing the effectiveness of the magnetic field generated by the vertical deflection coil 17. The front cover 19 and the back cover 20 are each formed into a predetermined shape using an insulating material such as a resin. The front cover 19 is attached to the front end of the deflection yoke 15, and the back cover 20 is attached to the rear end of the deflection yoke 15.

Here, a pair of upper and lower horizontal deflection coils 1 is used.
6 is wound in a saddle shape on a separator (also called a coil bobbin) not shown. Further, a pair of right and left vertical deflection coils 18 are also wound in a saddle shape around a separator (not shown).

FIG. 3 is a front view when the winding state of the vertical deflection coil is viewed from the front end side of the yoke (the panel side of the cathode ray tube). In FIG. 3, a separator 21 is made of an insulating material such as a resin, and is formed in a substantially conical cylindrical shape as a whole. A guide rib (not shown) for winding is formed on the inner peripheral surface of the separator 21. With respect to the separator 21, a coil wire (magnet wire or the like) constituting the pair of vertical deflection coils 18 is provided with a deflection yoke 15.
One side (the left side in the figure) and the other side (the right side in the figure) are bounded by the Y axis, which is the vertical axis, and are wound in a saddle shape by section winding using the guide ribs.

More specifically, the coil wire of the vertical deflection coil 18 is wound radially on the inner peripheral surface of the separator 21 when viewed from the front end side of the yoke. Further, two openings (a large-diameter opening and a small-diameter opening) formed at the front and rear ends of the separator 21 have vertical deflection coils 18.
Are passed in the circumferential direction so as to intersect with the X axis which is the horizontal axis of the deflection yoke 15.

Further, as described above, the vertical deflection coil 18
As shown in FIG. 4, the auxiliary coil 22 is wound on one of the four winding regions (upper right region in the drawing) divided by the X axis and the Y axis. Have been. This auxiliary coil 22 is located at X
It is wound on the inner peripheral surface of the separator 21 in the form of a substantially inverted triangle around an axis forming a predetermined angle θ (eg, θ ≒ 45 °) with the axis.

The coil wire (magnet wire or the like) of the auxiliary coil 22 is wound in a ring shape with a predetermined number of turns, for example, in a direction indicated by an arrow (or a direction opposite thereto). Incidentally, in the manufacturing process (coil winding step) of the deflection yoke 15, the auxiliary coil 22 may be wound after the vertical deflection coil 18 is wound on the common separator 21, or the auxiliary coil 22 may be wound. After the wiring, the vertical deflection coil 18 may be wound. Further, the coil wire of the auxiliary coil 22 may be wound using a guide rib formed on the inner peripheral surface of the separator 21, or separately.
A winding portion may be provided by providing a winding guide portion (projection or the like).
Further, the winding position, winding shape and number of turns of the auxiliary coil 22 can be arbitrarily changed.

The auxiliary coil 22 wound on the separator 21 as described above is connected to form a closed circuit 24 together with the variable inductance coil 23 serving as variable inductance means, as shown in FIG. Specifically, one closed circuit 24 is formed by connecting one end and the other end of the auxiliary coil 22 wound on the separator 21 to one end and the other end of the variable inductance coil 23, respectively.

When the display device is operated with the deflection yoke 15 having the above configuration mounted on the cathode ray tube 10, a sawtooth current (horizontal deflection current) having a horizontal deflection cycle flows through the horizontal deflection coil 16 by a horizontal deflection circuit (not shown). On the other hand, a sawtooth current (vertical deflection current) having a vertical deflection cycle flows through the vertical deflection coil 17 by a vertical deflection circuit (not shown). Thus, a horizontal deflection magnetic field is formed by the horizontal deflection coil 16 and a vertical deflection magnetic field is formed by the vertical deflection coil 17.

At this time, since the auxiliary coil 22 wound on the separator 21 forms a closed circuit 24, a current is induced in the auxiliary coil 22 by the horizontal deflection magnetic field generated by the horizontal deflection coil 16. Thereby, the auxiliary coil 22
Generates a magnetic field corresponding to the flow of the induced current. At this time, the direction of the magnetic field generated by the auxiliary coil 22 is opposite to the horizontal deflection magnetic field (original magnetic field) according to Lenz's law.

As a result, at the portion corresponding to the winding position of the auxiliary coil 22, the magnetic field of the auxiliary coil 22 acts to cancel the horizontal deflection magnetic field of the horizontal deflection coil 16, so that the horizontal deflection magnetic field The strength will be partially reduced. As a result, the balance of the horizontal deflection magnetic field changes. For example, if there is a portion having an excessively high magnetic field intensity in the distribution of the horizontal deflection magnetic field, the auxiliary coil 2 is set so that the magnetic field intensity of that portion is appropriately reduced.
By setting the winding position, the winding shape, the number of winding turns, and the like, the balance of the horizontal deflection magnetic field can be improved and local misconvergence can be corrected. Such a convergence correction function is, in particular,
This can be suitably used when correcting local misconvergence at a screen corner.

In addition, since the variable inductance coil 23 is connected to the closed circuit 24 formed by the auxiliary coil 22, the inductance of the variable inductance coil 23 can change the inductance of the entire closed circuit 24. Thereby, the closed circuit 24
When the inductance of the auxiliary coil 22 decreases, the amount of current induced in the auxiliary coil 22 decreases. Conversely, when the inductance of the closed circuit 24 decreases, the amount of current induced in the auxiliary coil 22 increases. Can be adjusted. Therefore, it is possible to adjust the convergence correction amount by the auxiliary coil 22 by arbitrarily changing the intensity of the magnetic field generated by the auxiliary coil 22.

Further, by winding the auxiliary coil 22 on the separator 21 on which the vertical deflection coil 17 is wound, the number of components is not increased, and the vertical deflection coil 17 is not wound in the winding step of the deflection coil. Auxiliary coil 2 together
2 can be wound, so that there is almost no increase in the number of manufacturing steps. Therefore, it is possible to appropriately correct local misconvergence while keeping the manufacturing cost of the deflection yoke 15 as low as possible.

Next, another embodiment of the present invention will be described with reference to FIGS.

FIG. 6 is a front view of another embodiment of the present invention when the winding state of the auxiliary coil is viewed from the front end of the yoke. In FIG. 6, the auxiliary coil 22 is constituted by four coils L1, L2, L3, L4. These four coils L1, L2, L3, L4 are connected to the X axis and Y
It is wound on each of four winding areas divided by a shaft. That is, the coil L1 is located in the upper left area of the drawing,
Is the upper right area of the figure, coil L3 is the lower right area of the figure, coil L
4 is wound in the lower left area of the figure. Also, the coil L1
Is wound on the inner peripheral surface of the separator 21 in a substantially inverted triangle shape around an axis that forms a predetermined angle θ (for example, θ = 45 °) with the X axis when viewed from the front end side of the yoke. I have. The coil L2 is wound at a position symmetrical to the coil L1 with respect to the Y axis, the coil L3 is wound at a position symmetrical to the coil L1 with respect to the intersection of the X axis and the Y axis, and the coil L4 is wound at the X axis. Is wound at a position symmetrical to the coil L1 with reference to FIG.

Further, the coil wire (magnet wire or the like) of the auxiliary coil 22 is wound in an annular shape with a predetermined number of turns in the arrow direction (counterclockwise direction) in the upper left area of the figure, and then intersects the Y axis. In the direction of the arrow (circumferential direction) in the figure, and in the upper right area of the figure, after being wound in a ring with a predetermined number of turns in the direction of the arrow (counterclockwise), crossing the X axis It is passed in the direction of the arrow (circumferential direction) in the figure. Further, the coil wire of the auxiliary coil 22 is wound in a circular shape with a predetermined number of turns in the arrow direction (clockwise direction) in the lower right region of the figure, and then intersects the Y axis in the arrow direction (circle) in the figure. Circumferentially)
In the lower left area of the drawing, the winding is formed in a ring shape with a predetermined number of turns in the direction of the arrow (clockwise). Thereby, the four coils L1, L2, L
3 and L4, and each coil L1, L2,
L3 and L4 are wound so as to generate a magnetic field in the direction opposite to the horizontal deflection magnetic field by the currents induced respectively.

The four coils L1, L2, L
7, L4 are connected in series with each other as shown in FIG.
Together to form a closed circuit 24. Specifically, one end of the coil L1 (winding start side) wound on the separator 21 and one end of the coil L4 (winding end side)
Are connected to one end and the other end of the variable inductance coil 23, respectively, to form one closed circuit 24.

By forming the auxiliary coil 22 with the four coils L1, L2, L3, and L4, when the horizontal deflection magnetic field is formed by the horizontal deflection coil 16,
Each coil L1, L2, L3,
A current is induced in L4. Thereby, four coils L
1, L2, L3, and L4 respectively generate a magnetic field corresponding to the flow of the induced current. At this time, each coil L1, L
The directions of the magnetic fields generated by L2, L3 and L4 are opposite to the horizontal deflection magnetic field. Therefore, each coil L1, L2, L
The strength of the horizontal deflection magnetic field generated by the horizontal deflection coil 16 is partially weakened at the portions corresponding to the winding positions 3 and L4. As a result, it is possible to appropriately correct misconvergence (for example, misconvergence in which the position of the electron beam shifts in the horizontal direction at each corner of the screen) occurring in four regions of the screen divided by the X axis and the Y axis. Becomes

The auxiliary coil 22 (coils L1, L
By connecting the variable inductance coil 23 to the closed circuit 24 formed by (2, L3, L4), the inductance of the entire variable closed circuit 24 can be changed by the variable inductance function of the variable inductance coil 23. As a result, the amount of current induced in the auxiliary coil 22 can be adjusted.
Can be arbitrarily changed to control the convergence correction amount by the auxiliary coil 22.

Further, as an application example of this embodiment, FIG.
As shown in FIG. 3, four coils L1, L2, L3, and L4 forming the auxiliary coil 22 form four independent closed circuits 24A, 24B, 24C, and 24D, respectively, and the four closed circuits 24A, 24B, 24C,
Variable inductance coils 23A, 23
A configuration in which 3B, 23C, and 23D are connected may be adopted.

According to this configuration, each of the coils L1, L2,
At the portions corresponding to the winding positions of L3 and L4, the strength of the horizontal deflection magnetic field by the horizontal deflection coil 16 can be individually reduced. In addition, each inductance variable coil 2
3A, 23B, 23C, and 23D, each coil L1,
The amount of current induced in L2, L3, and L4 and the amount of convergence correction associated therewith can be individually adjusted and controlled.

In another embodiment of the present invention,
The auxiliary coil 22 is divided into four coils L1, L2, L3, L4
However, it is also possible to configure the auxiliary coil with, for example, two, three, or five or more coils. Also, the winding shape, winding position, and number of turns of the coil can be arbitrarily changed.

[0037]

As described above, according to the present invention, the current is induced by the action of the horizontal deflection magnetic field by the horizontal deflection coil, and the action of partially reducing the intensity of the horizontal deflection magnetic field by the magnetic field generated by the induced current. By winding the auxiliary coil formed on a common separator with the vertical deflection coil, it is possible to appropriately correct local misconvergence while minimizing an increase in manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an overall image of a cathode ray tube according to the present invention.

FIG. 2 is a half sectional view showing a configuration of a deflection yoke according to the present invention.

FIG. 3 is a front view showing a winding state of a vertical deflection coil in the embodiment of the present invention.

FIG. 4 is a front view showing a winding state of an auxiliary coil in the embodiment of the present invention.

FIG. 5 is a configuration diagram of a closed circuit according to the embodiment of the present invention.

FIG. 6 is a diagram showing a winding state of an auxiliary coil in another embodiment of the present invention.

FIG. 7 is a configuration diagram of a closed circuit according to another embodiment of the present invention.

FIG. 8 is a configuration diagram of a closed circuit in an application example of the present invention.

[Explanation of symbols]

Reference Signs List 10: cathode ray tube, 15: deflection yoke, 16: horizontal deflection coil, 17: vertical deflection coil, 21: separator, 22
... Auxiliary coil, 23 ... Inductance variable coil, 24
... closed circuit, L1, L2, L3, L4 ... coil

Claims (8)

[Claims] 1. A horizontal deflection coil for generating a horizontal deflection magnetic field, a vertical deflection coil wound saddle-shaped on a separator outside the horizontal deflection coil, and a current is induced by the horizontal deflection magnetic field generated by the horizontal deflection coil. A deflection coil for generating a magnetic field in a direction opposite to the horizontal deflection magnetic field by the induced current, the auxiliary deflection coil being wound around a predetermined portion of the separator on which the vertical deflection coil is wound. yoke. 2. The deflection yoke according to claim 1, wherein a closed circuit is formed by the auxiliary coil, and an inductance changing means is connected to the closed circuit. 3. The deflection yoke according to claim 1, wherein said auxiliary coil comprises a plurality of coils. 4. The apparatus according to claim 1, wherein the auxiliary coil comprises four coils, and the four coils are symmetrically arranged on an axis substantially 45 ° with the horizontal axis of the deflection yoke. Item 3. The deflection yoke according to Item 3. 5. The apparatus according to claim 3, wherein a plurality of coils constituting said auxiliary coil are connected in series to form one closed circuit, and said closed circuit is connected to an inductance changing means. Deflection yoke. 6. The deflection yoke according to claim 3, wherein a plurality of independent closed circuits are formed by a plurality of coils constituting the auxiliary coil. 7. The apparatus according to claim 6, wherein said plurality of closed circuits are respectively connected to inductance changing means.
A deflection yoke as described. 8. A horizontal deflection coil for generating a horizontal deflection magnetic field, a vertical deflection coil wound saddle-shaped on a separator outside the horizontal deflection coil, and a current is induced by the horizontal deflection magnetic field generated by the horizontal deflection coil. A deflection yoke that generates a magnetic field in a direction opposite to the horizontal deflection magnetic field by the induced current and includes an auxiliary coil wound at a predetermined portion of the separator on which the vertical deflection coil is wound. A display device characterized by the above-mentioned.