JPH09320491A - Auxiliary deflection yoke and deflection yoke device using the auxiliary deflection yoke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an uniform magnetic field in the auxiliary deflection yoke for correcting raster strain. SOLUTION: The auxiliary deflection yoke is so constituted that paired horizontal coils 12 and paired vertical coils 13 are so disposed while being wound with wires at opposite places faced to each other in the horizontal direction, and also at opposite placed faced to each other in the vertical direction respectively while the center point of a core 11 is being held. In this place, the core 11 is formed into a shape where a distance Re from the center point O of the core 11 to both end positions of the wiring area of each correction coil, is larger than a distance Ro from the center point O of the core 11 to the center position of the wiring area of each correction coil, for example a quardrangle frame shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auxiliary deflection yoke for correcting raster distortion and a deflection yoke device using the auxiliary deflection yoke.

[0002]

2. Description of the Related Art Conventionally, in a picture tube of a projection type display, a deflection yoke main body is equipped with an auxiliary deflection yoke for correcting raster distortion. As shown in FIG. 8, the conventional auxiliary deflection yoke (5) has a ring-shaped core (51) and a core.
A pair of horizontal correction coils (52) and (52) are placed at positions facing each other in the horizontal direction with the center point of (51) interposed, and a pair of vertical correction coils (53) and (53) are placed at positions facing the vertical direction. Composed of lines
(Actual development 63-198158 [H01J29 / 76]).

Here, each correction coil has 9 cores (11).
Although the winding area of 0 degree is assigned, the core (11) is provided with a chuck area for winding by an automatic winding device and a lead wire extending from both ends of the correction coil for the next correction coil winding process. Since a temporary winding area is required to keep the wires in a way that does not get in the way,
Is limited to 55 degrees to 60 degrees.

[0004]

However, in the auxiliary deflection yoke (5) whose winding area is at most 60 degrees, the core is
The distribution of the lines of magnetic force generated inside the (51) is distorted like a pincushion as shown in FIG. When the electron beam is deflected in the horizontal and vertical directions by the magnetic field distribution having such a distortion, a circular spot shape (6) is obtained at the center point of the core (51) as shown in FIG. Alternatively, the electron beam deflected in the vertical direction becomes a triangular spot shape (61) (62) that is sharp in the deflection direction, which causes a problem in image quality. In order to obtain a uniform magnetic field without such a problem, it is necessary to set the winding area θ of each correction coil to 120 degrees, but such a winding area cannot be realized.

It is possible to reduce the pincushion distortion to some extent by providing a hollow region in which no winding is provided at the center of the winding region θ of each correction coil (52) (53). However, in order to secure a sufficient number of turns for each correction coil, the angle of the hollow region cannot be set excessively large, and it is impossible to completely eliminate the pincushion distortion.

An object of the present invention is to provide an auxiliary deflection yoke which can obtain a uniform magnetic field and a deflection yoke device using the auxiliary deflection yoke.

[0007]

An auxiliary deflection yoke according to the present invention has a ring-shaped core (11) which is to be mounted so as to surround the neck portion of a picture tube, and which is horizontally arranged with the center point of the core (11) interposed therebetween. A pair of horizontal correction coils (12) (12) at a position facing each other, and a pair of vertical correction coils (13) (1) at a position facing vertically.
It is constructed by winding 3). Here, the core (11) is the core (1
A shape in which the distance Re from the center point O of 1) to both ends of the winding area of each correction coil is larger than the distance Ro from the center point O of the core (11) to the center position of the winding area of each correction coil. have.

In the conventional auxiliary deflection yoke, the core is formed in an annular shape, and the distance from the center point of the core to the positions of both ends of each winding region and the distance from the center point of the core to the center position of each winding region. It is the same as the distance. In such an auxiliary deflection yoke, both ends of each auxiliary coil are close to the electron beam passage region, and the emission angle of the magnetic force lines at both ends of the coil is an angle inclined to the inside of the core with respect to the vertical line or the horizontal line. The pincushion distortion was generated in the magnetic field in the electron beam passage region. On the other hand, in the above-mentioned auxiliary deflection yoke of the present invention, the distance Re from the center point O of the core (11) to both end positions of each winding region is the center position O of the core (11) to the center position of each winding region. Since it is larger than the distance Ro to, the positions of both ends of the auxiliary coil are
Magnetic field lines emitted from both ends of each auxiliary coil, which are far from the center point of (11), form a magnetic field having some distortion outside the regions near both ends of the coil, that is, outside the region through which the electron beam passes. A uniform magnetic field is obtained in the electron beam passage region sufficiently distant from both ends of the coil.

Specifically, the core (11) is formed in a frame having a quadrangular outer shape, and a pair of vertically extending frame portions respectively have
A horizontal correction coil winding area is provided, and a vertical correction coil winding area is provided in each of the pair of horizontally extending frame portions. In the specific configuration, the horizontal correction coil (12)
Magnetic field lines are emitted in the vertical direction from both ends of the vertical correction coil (13), and magnetic field lines are emitted in the horizontal direction from both ends of the vertical correction coil (13). .

More specifically, the core (11) is formed by combining four core pieces (14), and each core piece (14) is provided with a winding region. In this case, each core piece (14) is in the shape of a straight rod, and each core piece (14) can be individually wound before the core pieces (14) are combined. Line work is easy. Further, since it is not necessary to entangle the lead wires extending from both ends of the correction coil, the winding can be provided over the entire length of the core piece (14).

Further, in a specific configuration, each winding region is provided with a hollow region in which no winding is substantially provided in the central portion. This makes each correction coil magnetically equivalent to a coil longer than its length, and
It is possible to form a uniform magnetic field over the entire area inside 1).

Further, the core (11) is provided with a protrusion (15) projecting toward the center of the core (11) in the hollow region of each winding region. As a result, the deflection sensitivity of each correction coil can be increased.

The deflection yoke device according to the present invention is constructed by attaching the auxiliary deflection yoke (1) according to the present invention to the deflection yoke body (2). This allows the auxiliary deflection yoke
A uniform magnetic field is formed inside the core (11) of (1), and the raster distortion is accurately corrected. Further, in a specific configuration, the core (11) of the auxiliary deflection yoke (1) is formed into a frame body having a quadrangular outer shape, and a horizontal correction coil winding region is provided in each of a pair of vertically extending frame portions. At the same time, a vertical correction coil winding region is provided in each of the pair of horizontally extending frame portions. On the other hand, in the deflection yoke body (2), the auxiliary deflection yoke (1) is closely attached to the outer peripheral surface of the auxiliary deflection yoke (1).
A holding member (3) to be held is attached.

In this specific structure, since the core (11) has a quadrangular shape and is non-rotatably restrained by the holding member (3) of the deflection yoke body (2), the core (11) is smaller than the circular core. Positioning in the direction of rotation 11) is performed with high accuracy.

[0015]

According to the auxiliary deflection yoke and the deflection yoke device using the same according to the present invention, a uniform magnetic field can be formed inside the core.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. As shown in FIG.
The auxiliary deflection yoke (1) according to the present invention has a pair of horizontal correction coils (12) (12) and vertical correction coils (13) (13) wound around an annular core (11) having a quadrangular outer shape. Composed. Here, a winding region is provided on each side of the core (11) over substantially the entire length, and each winding region is located at the center of the actual winding region A, where the winding is performed at a predetermined density. , Has a hollow region B where only the crossover exists. In the auxiliary deflection yoke (1), since the core (11) is rectangular, the center point O of the core (11) is O.
From the core (11) to the distance Re from each winding area to both ends
Is larger than the distance Ro from the center point O to the center position of each winding region.

2 and 3 show the auxiliary deflection yoke (1).
1 shows a deflection yoke device equipped with a holding member (3) for holding the auxiliary deflection yoke (1) in the deflection yoke body (2), and an auxiliary deflection yoke held by the holding member (3).
A cover (4) covering (1) is attached. Holding member (3)
Are four plate-shaped ribs (on the disk-shaped base plate (31) for tightly adhering to the outer peripheral surface of the auxiliary deflection yoke (1) and holding the auxiliary deflection yoke (1) at a predetermined position in a non-rotatable manner. 32) is provided so as to project.

The inventors have found that the auxiliary deflection yoke according to the present invention.
To demonstrate the performance of (1), 3 shown in FIGS. 7 (a) (b) (c)
Create a kind of auxiliary deflection yoke (1a) (1b) (1c),
The distribution of magnetic field lines was examined. As shown in FIG. 7 (a), when the correction coils (12) and (13) having no hollow area are wound around the rectangular core (11) along the entire length of each side, as shown by arrows in the figure. Although the distribution of magnetic force lines is slightly pincushion-like, the distortion is smaller than that of the conventional auxiliary deflection yoke (5) shown in FIG. This is because the winding area of the core (11) extends straight, so that the positions of both ends of each correction coil (12) (13) are smaller than those of the conventional annular core. It is considered that this is because the region where the pincushion distortion occurs is dispersed in the direction away from the center point of the core (11) due to the distance from the center point.

On the other hand, as shown in FIG. 7 (b), the winding areas of the correction coils (12) and (13) are divided into three equal parts, and the actual winding areas A'and A'and the hollow area B are formed. When ′ is provided, the magnetic force line distribution has a barrel shape as indicated by an arrow in the figure. It is considered that this is because each of the correction coils (12) and (13) in FIG. 7B exhibits characteristics equivalent to those of the coils longer than the correction coils (12) and (13) in FIG. 7A. When the substantial coil length increases in this way, the positions of both ends of the coil also increase accordingly.
It becomes further away from the center point of 1), and the distribution of magnetic field lines reverses from the bobbin shape to the barrel shape. Therefore, if you adjust the hollow area of each correction coil (12) (13) to an appropriate length,
It is presumed that an intermediate magnetic field between the bobbin winding magnetic field shown in FIG. 7A and the barrel magnetic field shown in FIG. 7B, that is, a uniform magnetic field can be obtained.

Therefore, as shown in FIG. 7 (c), the hollow area B of each horizontal correction coil (12) (13) is replaced by the hollow area B'of FIG. 7 (b).
When the auxiliary deflection yoke (1c) having a shorter length was manufactured, a complete uniform magnetic field was obtained over the entire inner region of the core (11) as indicated by an arrow in the figure.

In the above embodiment, the core (11) is molded as an integral body as shown in FIG. 4, but as shown in FIG. 5, it is constructed by combining four straight rod-shaped core pieces (14). It is also possible to do so. This allows each core piece (1
Winding work for 4) can be facilitated.
If the core piece (14) wound with the horizontal correction coil (12) and the core piece (14) wound with the vertical correction coil (13) are prepared in advance, these core pieces (14 ) Can be combined to meet various winding specifications. Further, as shown in FIG. 6, four protrusions (15) protruding toward the center of the core (11) can be formed on the core (11) to increase the deflection sensitivity.

As described above, in the auxiliary deflection yoke according to the present invention, not only the uniform magnetic field is obtained inside the core (11), but also each winding region of the core (11) extends straight, so that The winding region can be formed longer than the ring core, and the number of windings can be increased. or,
The four corners of the core (11) are non-winding regions, and these regions can be used as a chuck region by the automatic winding device or as a temporary winding region of the lead wire.

Further, in the deflection yoke device shown in FIG. 3, the auxiliary deflection yoke is provided by the ribs (32) of the holding member (3).
Since the positioning and rotation prevention of (1) are performed at the same time, the position and orientation of the auxiliary deflection yoke (1) can be defined with high accuracy. The core (11) of the auxiliary deflection yoke (1) is 4
In the case of the book core pieces, these core pieces are simply fixed in a holding member without being fixed to each other.
(3) When mounted on the top, these core pieces are held by the ribs (32) and fixed to each other in this state, so that the assembling work becomes simple.

The description of the above embodiments is for the purpose of explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope thereof.
In addition, the configuration of each part of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made within the technical scope described in the claims. For example, the core (11) is not limited to an annular shape with four corners at right angles, and a substantially rectangular annular core with four corners or an octagonal annular core can be used. Various shapes can be adopted as long as they are farther from the center of the core than in the case of the core.

[Brief description of drawings]

FIG. 1 is a plan view of an auxiliary deflection yoke according to the present invention.

FIG. 2 is a perspective view of a deflection yoke device according to the present invention.

FIG. 3 is an exploded perspective view of the deflection yoke device.

FIG. 4 is a perspective view of an integrated core.

FIG. 5 is a perspective view of a combination type core.

FIG. 6 is a perspective view of a core having protrusions formed on its inner peripheral surface.

FIG. 7 is a plan view showing distribution of magnetic force lines in various auxiliary deflection yokes.

FIG. 8 is a plan view of a conventional auxiliary deflection yoke.

FIG. 9 is a diagram showing the shape of a beam spot in a conventional auxiliary deflection yoke.

[Explanation of symbols]

 (1) Auxiliary deflection yoke (11) Core (12) Horizontal correction coil (13) Vertical correction coil (2) Deflection yoke body (3) Holding member (32) Rib (4) Cover

Claims (7)

[Claims] 1. An auxiliary deflection yoke for compensating for raster distortion, comprising an annular core (11) which is to be mounted so as to surround the neck portion of a picture tube, and which is horizontal with a center point of the core (11) interposed therebetween. A pair of horizontal correction coils (1
2) and (12), a pair of vertical correction coils (13) and (13) are wound at positions facing each other in the vertical direction, and the core (11) is the core (1).
A shape in which the distance Re from the center point O of 1) to both ends of the winding area of each correction coil is larger than the distance Ro from the center point O of the core (11) to the center position of the winding area of each correction coil. An auxiliary deflection yoke having. 2. The core (11) is formed in a frame body having a quadrangular outer shape, and a pair of vertically extending frame portions are respectively provided with horizontal correction coil winding regions and a pair of horizontally extending frame portions. The auxiliary deflection yoke according to claim 1, wherein each of the auxiliary deflection yokes has a vertical correction coil winding region. 3. The auxiliary deflection yoke according to claim 2, wherein the core (11) is configured by combining four core pieces (14), and each core piece (14) is provided with a winding region. 4. The auxiliary deflection yoke according to claim 1, wherein each winding region is provided with a hollow region in which a winding is not substantially provided in a central portion. 5. The auxiliary deflection yoke according to claim 4, wherein the core (11) is provided with a protrusion (15) projecting toward the center of the core (11) in a hollow region of each winding region. . 6. In a deflection yoke device constituted by attaching an auxiliary deflection yoke (1) for correcting raster distortion to a deflection yoke body (2), the auxiliary deflection yoke (1) comprises:
An annular core (11) to be attached so as to surround the neck portion of the picture tube, a pair of horizontal correction coils (12) (12) at positions horizontally opposed to each other with the center point of the core (11) interposed therebetween, A pair of vertical correction coils (13) and (13) are wound at positions facing each other in the vertical direction, and the core (11) is located in the winding area of each correction coil from the center point O of the core (11). A deflection yoke device having a shape in which a distance Re to both end positions is larger than a distance Ro from a center point O of the core (11) to a center position of a winding region of each correction coil. 7. The core (11) of the auxiliary deflection yoke (1) is formed into a frame having a quadrangular outer shape, and a pair of vertically extending frame portions are provided with horizontal correction coil winding regions, respectively. A vertical correction coil winding region is provided in each of the pair of horizontally extending frame portions, and the deflection yoke body (2) is closely attached to the outer peripheral surface of the auxiliary deflection yoke (1).
7. The deflection yoke device according to claim 6, further comprising a holding member (3) attached thereto.