JPS589541B2 - Henkou York - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic beam deflection yoke for use in a television receiver.

Generally, a deflection yoke is composed of a pair of horizontal deflection coils, a pair of vertical deflection coils, and an annular core.

In particular, bush-shaped deflection coils are often used for the purpose of reducing deflection power.

As is well known, the saddle-shaped deflection coil consists of a pair of parallel longitudinal force direction parts, a front end part of the longitudinal force direction parts located on the picture tube image plane side, and a rear end part located on the electron gun side. A window is formed in the center.

In addition, the saddle-shaped deflection coil is manufactured by winding the wire rod by supporting the window width at the front end and the window width at the rear end, but depending on the winding tension of the wire, The longitudinal portion forming the window between the front and rear ends tends to be straight.

However, since the deflection yoke is mounted on a curved surface, which is the junction of the picture tube consisting of a cylindrical portion and a spherical portion, the window side of the deflection coil cannot be provided on the shortest line along the curved surface. Ta.

In addition, if the saddle-shaped deflection coil is classified according to the tube axis direction,
In general, as shown in Fig. 1, there is an entrance area a on the entrance side of the electron beam, a main deflection area b, and an exit side area C on the image plane side, and the magnetic flux distribution in each cross section in the tube axis direction is uneven. It is represented by a uniform curve.

In particular, the deflection magnetic field in the exit side region C of the saddle-shaped deflection coil strongly acts on the raster shape in addition to the convergence at a part of the corner of the image plane, so the window width at the front end of the saddle-shaped deflection coil inevitably will be regulated.

In addition, the main deflection area has a strong pincushion-shaped magnetic flux distribution as indicated by the peaks in the positive direction, and although the deflection magnetic field in this main deflection area still acts on the entire image plane, it is particularly concentrated on the image plane. It acts most strongly on the intermediate side between the center and part of the corner.

However, if the main deflection region exhibits a strong pincushion-shaped magnetic flux distribution tendency, a waveform misconvergence called S-ing occurs, making it impractical.

This will be explained in terms of horizontal deflection coils.

When a strong pincushion-shaped magnetic flux distribution tendency appears in the horizontal deflection magnetic field, a vertical component is generated in the horizontal deflection component, and the vertical component increases as it approaches a part of the corner of the image plane.

This state will be outlined using an in-line electron beam with reference to FIG.

A green beam G is placed at the origin of the image plane indicated by the x and y axes, a red beam R is placed in the positive direction on the X axis, and a blue beam B is placed in the negative direction.

In Fig. 2, the green beam G draws a predetermined pattern at both the upper and lower points on the image plane, but the blue beam B
and red beam R respectively have amplitudes in the y-axis direction on the side where the electron gun is located so as to approach the This results in a so-called positive cross-convergence state.

However, at each corner, a state of reverse cross-convergence occurs due to the relationship of the magnetic field in the exit side region of the saddle-shaped deflection coil, resulting in S-ing misconvergence.

The amplitude of the S-swing distortion increases as it moves away from the origin in the y-axis direction.

Therefore, in order to lower the peak in the positive direction of the main deflection region in Fig. 1 and weaken the strong pincushion-shaped magnetic flux distribution, the width of the window at the rear end that restricts the window of the saddle-shaped deflection coil is made extremely large. It is also possible to make it smaller and almost dot-shaped.

However, in the embodiment of FIG. 2, the magnetic field in the entry side region of the saddle-shaped deflection coil acts strongly on the green beam G, which is the central electron beam, and in the saddle-shaped deflection coil configured as described above, the magnetic field acts strongly on the green beam G, which is the central electron beam. The negative valley in the approach side region in Figure 1 becomes a magnetic flux distribution with a strong barrel-shaped tendency, and as shown on the X-axis in Figure 2, the amplitude of the green beam G is much higher than that of the other two electron beams. It has the disadvantage of being large.

This drawback occurs on the entrance side of the electron beam, so
This phenomenon becomes more and more magnified in the visual field,
This also could not be put to practical use, and a compromised deflection yoke had to be used.

The present invention provides a deflection yoke that eliminates the above drawbacks, and embodiments of the present invention will be described with reference to the drawings.

In FIG. 3, reference numeral 1 denotes a saddle-shaped deflection coil, which includes a pair of parallel longitudinal parts 11, and a front end 12 and a rear end 13 by connecting the front and rear ends of the longitudinal parts, respectively. A window 14 is formed in the center.

An auxiliary deflection coil 2 is disposed within the window portion corresponding to the main deflection area of the saddle-shaped deflection coil.

The auxiliary deflection coil 2 can be formed by winding a wire 21 in advance as shown in FIG. 4, or it can be formed by printing a conductor 23 in a coil shape on a particularly flexible insulating substrate 22 as shown in FIG. But that's fine.

The saddle-shaped deflection coil 1 and the auxiliary deflection coil 2 are connected in series as shown in FIG. 6 and are formed so as to generate magnetic flux in the same direction as shown by the arrows.

Note that the dotted line is a line on the longitudinal part indicating the window width in a conventional single saddle-shaped deflection coil, or in the present invention, the window width in the exit side area is set wider than the conventional one, and the overall width is increased. This is to prevent distortion from occurring.

Therefore, in the main deflection region of the saddle-shaped deflection coil, which is configured by setting the optimal magnetic field in the exit side region, an auxiliary deflection coil that generates magnetic flux in the same direction is provided, so that only the saddle-shaped deflection coil described above is provided. Compared to the case of , the main deflection region has a pincushion-shaped magnetic flux distribution with more barrel-shaped inclination.

Therefore, the peak in the positive direction of the main deflection region in FIG. 1 is lowered, resulting in a deflection magnetic field in which the strong pincushion-shaped magnetic flux distribution is relaxed.

As a result, a saddle-shaped deflection coil having good convergence characteristics can be obtained.

In particular, the auxiliary deflection coil is set so that it does not reach the exit side region of the electron beam, and by expanding the window width, adverse effects on the raster can be sufficiently avoided.

Incidentally, as is clear from FIG. 6, it goes without saying that the above-mentioned configuration can be used for a pair of saddle-shaped deflection coils facing each other, and both the horizontal and vertical deflection coils may have the above-described configuration. , only one set of deflection coils may have the above configuration. Therefore, according to the deflection yoke according to the present invention, the complicated eswing (S) that occurs in color television receivers can be avoided.
ing) Misconvergence can be easily removed and there is no risk of raster distortion occurring.

Furthermore, there is no need to make any changes to the conventional mechanical winding method, the saddle-shaped deflection coil and the auxiliary deflection coil can be mass-produced individually, and extremely high-performance magnetic field characteristics can be achieved. It is possible to provide a deflection yoke with

[Brief explanation of the drawings] Fig. 1 is an explanatory diagram of the magnetic flux distribution divided in the tube axis direction of a general saddle-type deflection coil, Fig. 2 is a schematic explanatory diagram of misconvergence, and Fig. 3 is an explanatory diagram of the magnetic flux distribution in the tube axis direction of a general saddle-type deflection coil. FIGS. 4 and 5 are plan views of an embodiment of the saddle-shaped deflection coil, FIGS. 4 and 5 are diagrams illustrating an embodiment of the auxiliary deflection coil in the present invention, and FIG. 6 is a diagram illustrating a connected state.

Claims (1)

[Claims] 1. In an electromagnetic beam deflection yoke for a picture tube each consisting of a pair of horizontal and vertical deflection coils, at least one of the deflection coils is formed as a saddle-shaped deflection coil having a window in the center, and the saddle-shaped deflection A deflection yoke characterized in that an auxiliary deflection coil connected in series with the saddle-shaped deflection coil is disposed within the window portion corresponding to the main deflection area of the coil.