JPS62217546A - Deflection yoke - Google Patents

Abstract

PURPOSE:To reduce convergence coma and coma aberration of a beam spot by providing the first and second magnetic material pieces which generate an auxiliary vertical deflection magnetic field in a pin cushion form in the region on the side of an electron gun while picking up a leak of the vertical deflection magnetic field on a deflection yoke. CONSTITUTION:A vertical deflection coil 1 generates a vertical deflection magnetic field strained in a barrel form while a horizontal deflection coil generates a horizontal deflection magnetic field strained in a pin cushion form. Then, the vertical deflection magnetic field shown in a broken arrow leaks from a core 15 while said leakage magnetic field is collected at the respective main surface parts 8 and 9 of the first and second magnetic material pieces 6 and 7 so that an auxiliary vertical magnetic field of distribution in the pin cushion form shown by a real arrow is generated on the side of an electron gun by four branch parts 10a, 10b; 11a, 11b. Thereby, a convergence coma and coma aberration of a beam spot can be cheaply reduced.

Description

[Detailed Description of the Invention] 3. Field of Industrial Application The present invention is mainly intended for use in a pincushion-shaped color picture tube that is attached to a color picture tube equipped with an in-line electron gun. This invention relates to a deflection yoke that generates a horizontally distorted horizontal deflection magnetic field and a barrel-shaped vertical deflection magnetic field.

2. Description of the Related Art In general, a deflection yoke attached to a color picture tube equipped with an in-line electron gun includes a saddle-type horizontal deflection coil and a toroidal-type vertical deflection coil. The horizontal deflection coil generates a horizontal deflection magnetic field with a large pink-fushon distortion component as shown in Figure 5, and the vertical deflection coil generates a vertical deflection magnetic field with a large barrel distortion component as shown in Figure 6. Therefore, a so-called self-convergence configuration that does not require a dynamic convergence circuit is likely to cause a so-called convergence coma, in which the green raster G generated by the beam and the red and blue rasters R and B generated by the electron beams on both sides are shifted in the upper and lower parts. There was a problem. In addition, as shown in FIG. 8, beam spots r and b [
There was also the problem that rotational distortion (coma distortion) was likely to occur.

In particular, this coma distortion cannot be ignored in devices that use large or wide-angle color picture tubes, or in so-called pincushion-less devices that correct raster distortion on the left and right sides of the screen by adjusting the magnetic field distribution. . These undesirable phenomena are related to the barrel-like distribution of the vertical deflection magnetic field, especially on the electron gun side.In particular, in order to correct left-right pincushion distortion of the raster, the vertical deflection magnetic field is changed as shown in Figure 9. This phenomenon becomes more noticeable in devices that have a stronger barrel tendency on the electron gun side as a compensation for distorting the phosphor screen surface side into a pincushion-like distribution.

Means for Solving the Problems The deflection yoke of the present invention includes first and second magnetic pieces that pick up leakage of the vertical deflection magnetic field and generate a pincushion-like auxiliary vertical deflection magnetic field in the electron gun side region. Be prepared. The first and second magnetic pieces each have a main surface facing each other via a vertical axis, and extend horizontally from the upper and lower edges of the main surface to form the electron gun side cylindrical portion of the insulating frame. It has two branch parts that protrude toward the electron gun side along the outer surface, and the branch part when viewed from the central axis of the cylindrical part is at an angle of 200 mm with respect to the horizontal axis.
It is located within a region that starts with an inclination angle of 45° or more and ends with an inclination angle of 45° or more.

Function: With such a configuration, each main surface of the first and second magnetic pieces acts as a collector that picks up leakage of the vertical deflection magnetic field, and the two pairs of branched parts extending from this serve as collectors for collecting the leakage of the vertical deflection magnetic field. It generates an auxiliary vertical deflection magnetic field of
By attaching a small magnetic piece commonly known as an enhancer shunt to the tip of the electron gun, it is possible to reduce the coma distortion of the convergent beam spot without the need for turrets.

Embodiment To explain the deflection yoke of the present invention together with the embodiment shown in FIG. It supports a coil, and has a cylindrical part 6 at the end on the electron gun side that is connected to the cone part 3 via the box part 4 and into which the neck part of a color picture tube equipped with an in-line electron gun is inserted. There is. On both outer surfaces of the box-shaped portion 4,
Each main surface portion 8°9 of the first and second magnetic material pieces 6.7 is
Two branch portions 10& are fixed to each other so as to face each other via a vertical axis, and extend horizontally from each of the upper and lower edges of the main surface portion 8.9.

10b; 11a and 11b extend along the back surface of the box-shaped portion 4 and then protrude along the outer surface of the cylindrical portion 6 toward the electron gun side. The box-shaped portion 4 accommodates the electron gun-side arc-shaped portion of the horizontal deflection coil, and each pair of branch portions 10& of the first and second magnetic pieces 6.7.

1ob: 11a and 11b are arranged symmetrically across the vertical axis, and also symmetrically across the horizontal axis.

When viewed from the back side, as shown in Fig. 2, the cylindrical part 6
Each upper branch 10a, 10b; 11&.

11b is curved in an arc shape along the outer circumferential surface of the cylindrical portion 5, but is slightly spaced from the outer circumferential surface. Therefore, there is no problem in attaching the tightening band 12 for fixing the insulating frame 2 to the neck of the color picture tube. And each branch part 10&, 10b;1 on the cylindrical part 6
1 &, 11b are 36° ± 100° and 45°
The angle is set to 90° or more, preferably 85°±3°.

The vertical deflection coil 1 generates a vertical deflection magnetic field distorted into a barrel shape, and the horizontal deflection coil generates a horizontal deflection magnetic field distorted into a pincushion shape. leaks from the core 15, and this leakage magnetic field is applied to each main surface portion 8.9 of the first and second magnetic material pieces 6.7.
As a result, an auxiliary vertical deflection magnetic field with a pincushion-like distribution shown by solid arrows in FIG.
2L.

101); 0 generated on the electron gun side by 11 a and 1 l b.
9 does not have to be planar, and may be formed in a semicircular arc shape centered on the tube axis or in other shapes. In addition, branch part 1
0a, 10t): 11a.

The protruding edge of 11b does not need to be arcuate, and may have a planar or other shape.

Effects of the Invention Since the present invention is constructed as described above, the vertical deflection magnetic field having a barrel-like distribution is shaped into a pincushion-like distribution on the electron gun side, and the coma distortion of convergence coma and beam spotting can be reduced at low cost. Obtainable.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a deflection yoke embodying the present invention, Fig. 2 is a rear view of the deflection yoke, Figs. 3 and 4 are explanatory diagrams of the operation of the deflection yoke, and Figs. Figure 7 is a diagram showing the distortion of the horizontal and vertical deflection magnetic fields, and Figure 7 is a diagram explaining the convergence coma caused by the conventional deflection yoke.
FIG. 8 is a diagram showing coma distortion of a beam spot, and FIG. 9 is a diagram showing distortion of a vertical deflection magnetic field caused by a conventional deflection yoke. 1... Vertical deflection coil, 2... Insulating frame, 6°... Magnetic material piece. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 10a- Figure 3 Figure 4 Figure 5 Figure 6 Figure 8 Figure 9

Claims (1)

[Claims] A horizontal deflection coil that generates a horizontal deflection magnetic field distorted in a pincushion shape, a vertical deflection coil that generates a vertical deflection magnetic field distorted in a barrel shape, and a cylindrical part on the electron gun side that supports both the horizontal and vertical deflection coils. and first and second magnetic pieces that magnetically couple with a portion of the vertical deflection magnetic field to generate a pincushion-shaped auxiliary vertical deflection magnetic field, The magnetic material pieces 2 have main surfaces facing each other via a vertical axis, and 2 magnetic material pieces extending horizontally from the upper and lower edges of the main surfaces and protruding toward the electron gun side along the outer surface of the cylindrical portion. When viewed from the central axis of the cylindrical part, the branch part has two branch parts with respect to the horizontal axis.
A deflection yoke characterized in that the deflection yoke is located within a region starting from an inclination angle of 0° or more and ending at an inclination angle of 45° or more.