JPS6318300B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a deflection device installed in a color picture tube equipped with an in-line electron gun (a system in which three electron guns are arranged horizontally in a straight line), and particularly to a deflection device for reducing convergence and screen distortion. The present invention relates to a deflection device that can be automatically corrected using a deflection magnetic field.

Conventionally, in the case of a color picture tube equipped with an in-line electron gun, the deflection magnetic field distribution of the deflection device is converged using a deflection device that generates a pincushion type for the horizontal magnetic field 11 and a barrel type for the vertical magnetic field 12, as shown in Figure 1. The image quality and vertical screen distortion are automatically corrected. If such a magnetic field distribution is used, an elastic pink tension type left and right screen distortion will occur, so a method is also used to correct this left and right screen distortion by supplying a parabolic current synchronized with the vertical magnetic field to the horizontal deflection coil from an external circuit. ing. In the figure, (oz) indicates the electron gun side - the screen side.

In order to also omit the external correction of left and right screen distortion, which is a drawback of the deflection device as described above, the horizontal magnetic field 21 is of a pink tension type as shown in FIG. 2, and the vertical magnetic field 22 is of the electron gun side. A stronger barrel shape may be used, and a weaker barrel shape or pink tension shape may be used on the screen side. Such magnetic fields can be created by various methods, and some of them have already been put into practical use in color picture tubes with deflection angles of 90° or less, but special measures are required to create a perpendicular magnetic field. be. The reason for this is that in the case of the vertical magnetic field shown in FIG. 2, a non-uniformity is required in which the vertical magnetic field is reversed between the electron gun side and the screen side.

Next, an example of a deflection device for obtaining a perpendicular magnetic field having non-uniformity as described above will be explained.

As a first example, as shown in Figs. 3 and 4, the strong barrel-shaped magnetic field distribution on the electron gun side is formed by the distribution of the winding 32 toroidally wound around the truncated cone-shaped core 31, and is generated simultaneously. It has a structure in which a strong barrel-shaped magnetic field distribution on the screen side is shaped into a pincushion shape using a magnetic piece 33 having a protrusion ₃₃₁ located near the maximum density of leakage flux on both the upper and lower toroidally wound windings 32. Yes, Japanese Patent Application Publication 1973
-75215, and this structure has 32 windings.
is wound approximately perpendicularly to the end surface of the core 31. In the figure, 34 is a separator, 35 is a horizontal coil, and ₃₅₁ is a bend-up portion of the horizontal coil.
However, in this example, there is a limit to the magnetic piece 33 that shapes a strong barrel-shaped magnetic field into a pincushion-shaped magnetic field. (approximately twice), it has the disadvantage that it is not possible to obtain a sufficiently strong pincushion magnetic field necessary for automatic correction.

As a second example, a structure as shown in FIGS. 5 and 6 is considered. This is winding 4 on core 41.
2, the winding angle on the electron gun side and the screen side of the core 41 is changed so that the electron gun side is closer to the horizontal axis X, and the screen side is closer to the vertical axis Y. In this method, the winding 42 is prevented from being bent vertically at the opening end of the core 41 on the electron gun side and the screen side, and the resulting distortion of the winding 42 and the resulting variations in convergence and screen distortion are prevented. However, the winding 52 is formed using a specially molded core 51 as shown in FIG. 7, or a guide ring 6 for fixing the winding is attached to the front and rear ends of the core 61 as shown in FIG.
2 must be used in combination. In other words, this structure requires a special core and guide ring, which makes the winding system complicated, lowering manufacturing efficiency, and requiring a complicated winding machine. This becomes even more difficult for wide-angle tubes, which have the disadvantage of making it difficult to form the necessary magnetic field.

The present invention has been made in view of the various drawbacks of the conventional deflection devices, and an object of the present invention is to provide a deflection device that can automatically correct convergence and left and right screen distortion even in a 110° deflection tube. .

Next, one embodiment of the deflection device of the present invention will be described with reference to FIGS. 9 and 10.

That is, it has a truncated conical shape and has a horizontal axis X and a vertical axis Y,
A truncated conical core 71 rotationally symmetrical with respect to a deflection center axis Z passing through the centers of these two axes, and a pair of toroidal vertical coils 72 wound approximately at right angles to the circumference of this core 71. and a pair of first protrusions 73 1 arranged symmetrically along the outer periphery near the screen-side opening of the core 71 and having protrusions 73 ₁ on the screen side on an axis substantially corresponding to the diagonal of the screen. 1 magnetic piece 73 and a pair of horizontal coils 75 attached to the vertical coil 72 with a separator 74 in between.
The horizontal coil 75 and the vertical coil 72 are interposed in a region from the electron gun side bend up 75 ₁ of the horizontal coil 75 to approximately the center of the electron gun side opening end and the screen side opening end of the core 71. and a pair of second magnetic pieces 76 arranged vertically symmetrically.

With this structure, the first magnetic body 73 acts to shape the screen side of the vertical magnetic field into a pincushion type magnetic field, similar to the magnetic piece 33 described in the conventional first structure. The size and position of the protrusion 73 ₁ and the core 71
It can be controlled within a certain range depending on the distance. Second
The magnetic piece 76 has the effect of shaping the pink-tension type magnetic field shown by the broken line 81 in FIG. It is possible to adjust the position.

On the other hand, when the vertical coil 72 is wound perpendicularly to the circumference of the opening end of the core 71 on both the electron gun side and the screen side, the vertical coil 72 has a barrel shape that is almost uniform in the area from the electron gun side to the screen side depending on its position on the circumference. It is possible to vary the magnetic field from a pink tension type magnetic field.

As described above, the first magnetic piece 73 and its protrusion 73
By appropriately selecting and combining the dimensions and positions of _{the first} and second magnetic pieces 76 and the positions on the circumference of the openings on both the electron gun side and the screen side of the core 71 of the vertical coil 72, the vertical magnetic field can be reduced. Non-uniformity can be freely defined.

In order to automatically adjust the convergence and vertical and horizontal screen distortion using the deflection magnetic field, as mentioned above, the vertical deflection magnetic field should be shaped like a barrel, and the screen side should have a pink tension type, both of which have opposite non-uniformity. In general, the strength of this barrel-shaped magnetic field and the strength of the pink tension magnetic field must be increased as the deflection angle of the color picture tube using this deflection device increases and as the screen size increases. . Therefore, it was very difficult to use the conventional first and second structures for something like a large 110° deflection tube, but by using the structure of the present invention, It has become possible to realize this relatively easily.

The protrusion 73 ₁ of the first magnetic piece 73 is set on the axis corresponding to the diagonal of the screen, and the vertical coil 7
Keep the winding position of 2 within approximately ±60° from the X axis,
In an experiment using a deflection device in which the second magnetic piece 76 was set near the open end of the core 71 on the electron gun side,
The convergence error was within 1.5 mm, the vertical screen distortion was approximately 0.5%, and the horizontal screen distortion was approximately 1%, which was sufficient for practical use.

As mentioned above, the deflection device of the present invention is structurally simple, with magnetic pieces attached to the front and rear of the core of a conventional semi-toroidal deflection device, and the windings etc. are almost the same as the conventional deflection device. However, especially in wide-angle deflection tubes, it has extremely advantageous points in terms of performance, manufacturability, cost, etc., and therefore its industrial value is extremely large.

[Brief explanation of the drawing]

Fig. 1 is a curve diagram showing the magnetic field of a deflection device that automatically corrects convergence and vertical screen distortion; Fig. 2 is a curve diagram showing the magnetic field of a deflection device that automatically corrects convergence, vertical screen distortion, and horizontal screen distortion; 3 and 4 are diagrams showing a first example of a conventional deflection device, in which FIG. 3 is a side view, FIG. 4 is a simplified front view seen from the screen side, and FIGS. 5 and 6. FIG. 5 is a side view, FIG. 6 is a simplified front view seen from the screen side, and FIG. 7 is a diagram showing a second example of a conventional deflection device. FIG. FIG. 8 is a side view showing a core provided with a guide ring for winding the windings shown in FIGS. 5 and 6, and FIGS. FIG. 10 is a diagram showing one embodiment of the deflection device of the present invention, FIG. 9 is a side view, FIG. 10 is a simplified front view seen from the screen side, and FIG. 11 is a second embodiment of the deflection device.
FIG. 3 is an explanatory diagram showing how the vertical magnetic field changes due to the magnetic piece. 31, 51, 61, 71... Core, 32, 4
2, 52, 72... Vertical deflection coil, 33, 73
...First magnetic piece, 33 ₁ , 73 ₁ ...Protrusion, 3
5, 75...Horizontal deflection coil, 76...Second magnetic piece.

Claims (1)

[Claims] 1. A pair of saddle-shaped horizontal coils, a separator, and a pair of truncated cone-shaped cores, which are attached to the outer wall from the neck to the funnel of a color picture tube housing an in-line electron gun. and a toroidal vertical coil disposed near the maximum density of leakage magnetic flux of the toroidal vertical coil near the screen-side opening end of the core, each having a pair of protrusions in a diagonal direction of the screen of the color picture tube. a pair of magnetic pieces; the saddle-shaped horizontal coil and the toroidal-shaped vertical coil in a region from the electron gun-side bend up part of the saddle-shaped horizontal coil to approximately the center of the electron gun-side open end and the screen-side open end of the core; It consists of a pair of second magnetic pieces interposed between the coils, and the first magnetic piece and the second magnetic piece can automatically correct convergence and screen distortion in horizontal and vertical directions. A deflection device characterized by: 2. Deflection according to claim 1, wherein the first magnetic piece is configured to change the vertical magnetic field toward the pink tension side, and the second magnetic piece is configured to change the vertical magnetic field toward the barrel side. Device.