JPS62237648A - Deflection yoke - Google Patents

Abstract

PURPOSE:To make it possible to reduce a convergence coma and a beam spot coma distortion without reducing the horizontal deflecting efficiency, by producing an auxiliary vertical deflecting magnetic field and an auxiliary horizontal deflecting magnetic field of a pincushion form distribution by the first and the second magnetic pieces. CONSTITUTION:The vertical deflecting coil produces a vertical deflecting magnetic field ditorted in a burrel form, while the horizontal deflecting coil produces a horizontal deflecting magnetic field distortrd in a pincushion form. Since the vertical deflecting magnetic field is leaked from a core 4 and picked up by the main surfaces 8 and 9 of the first and the second magnetic pieces 6 and 7, an auxiliary vertical deflecting magnetic field is produced at the electron side by four tongues 10a, 10b, 11a, and 11b. And, since the main surfaces 8 and 9; and;the third and fourth tongues 15a, 15b, 16a, 16b act as a yoke to the horizontal magnetic field, the horizontal deflecting magnetic field is made stronger, and an auxiliary horizontal deflecting magnetic field of a pincushion form is produced at the elecron gun side. Therefore, the convergence coma or the beam spot coma distortion can be reduced without deteriorating the horizontal deflcting efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is mainly intended for use in a color picture tube equipped with an in-line electron gun to produce a horizontal deflection magnetic field distorted into a pincushion shape and a vertical deflection magnetic field distorted into a barrel shape. This relates to a deflection yoke that generates

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 pincushion distortion component as shown in Fig. 8, and the vertical deflection coil generates a vertical deflection magnetic field with a large barrel distortion component as shown in Fig. 9. Therefore, a so-called self-convergence configuration, which does not require a dynamic convergence circuit, can be achieved.

However, as shown in Figure 10, the green raster G produced by the center electron beam and the red and blue rasters R and B produced by the electron beams on both sides are likely to deviate in the upper and lower parts, resulting in a so-called convergence coma. There was a problem. Further, as shown in FIG. 11, there is a problem that rotational distortion (coma distortion) is likely to occur in the beam spots r and b caused by the electron beams on both sides.

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. .

Therefore, it is possible to provide a pair of magnetic pieces at the end of the deflection yoke on the electron gun side to pick up the leakage of the vertical deflection magnetic field, and use these magnetic pieces to generate an auxiliary vertical deflection magnetic field distorted into a pincushion shape. An attempt has been made, and with this configuration it was possible to considerably reduce convergence coma and coma distortion of the beam spot.

Problems to be Solved by the Invention However, since the electron gun side portion of the horizontal deflection magnetic field acts on the magnetic piece, there is a problem in that the horizontal deflection efficiency is reduced.

Means for Solving the Problems The present invention has been made to eliminate the above-mentioned problems. The first and second magnetic pieces generate an auxiliary vertical deflection magnetic field with a pincushion-like distribution and an auxiliary horizontal deflection magnetic field with a pincushion-like distribution.

That is, there is a main surface part that faces the first and second magnetic material pieces via the vertical axis and magnetically couples to the leakage magnetic fields of the horizontal and vertical deflections, and a main surface part that faces the first and second magnetic material pieces from above and below on the electron gun side end surface of this main surface part. first and second tongue-shaped portions extending horizontally and projecting toward the electron gun along the outer surface of the cylindrical portion of the insulating frame; and anti-electron 3F of the main surface portion. 'Third and fourth tongue-like parts are provided which extend horizontally from the upper and lower ends of the end face and project toward the tube axis side.

Operation: With this configuration, the first and second tongues provide an auxiliary vertical deflection field with a pincushion distribution, and the third and fourth tongues provide an auxiliary vertical deflection field with a pincushion distribution. A horizontal deflection magnetic field is generated on the electron gun side, respectively.
The convergence coma and beam spot can be reduced by 1 without reducing the horizontal deflection efficiency.

Embodiment To explain the deflection yoke of the present invention together with the embodiment shown in the drawings, an insulating frame 2 made of synthetic resin that supports a toroidal vertical deflection coil 1 has a saddle-shaped horizontal deflection coil (not shown) inside it. A cylindrical part 6 that supports the cone part 3 through the box part 4 and has an electron gun side end part through which the neck part of a color picture tube equipped with an in-line electron gun is inserted.
have. On both sides of the box-shaped part 4, the main surface parts 8.9 of the first and second magnetic pieces 6, 7 as shown in FIG. First and second tongue-shaped portions 101L are fixed to each other and extend horizontally from above and below at the electron gun side end portions of the main surface portions 8 and 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 5 toward the electron gun. The electron gun side circular arc portion of the horizontal deflection coil is housed in the box portion 4, and the first and second tongue portions 102L, 10b of the first and second magnetic pieces 6, 7 are housed in the box portion 4.
, 11&.

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. 3, the cylindrical part 5
tongues 10a, 10b, 11a on the outer surface of.

11b is curved in an arc shape along the outer peripheral surface of the cylindrical portion 5. However, since it is slightly spaced apart from the outer peripheral surface, it does not interfere with the attachment of the tightening band 12 for fixing the insulating frame 2 to the neck of the color picture tube. and first and second tongue-shaped portions 10a on the outer circumferential surface of the cylindrical portion 5.

10b, 11a, and 11b start from an inclination angle of θ1 with respect to the horizontal axis 14 when viewed from the central axis 13 of the cylindrical portion 6, and then angles of inclination of θ2
θ1 is 20° or more, preferably 36°±100, and θ2 is 46° or more 90°.
', preferably 86°±3°.

On the other hand, third and fourth tongue-shaped portions 16a and 1 extend horizontally from above and below at the ends of the main surfaces 8 and 9 on the side opposite to the electron gun.
5b, 16a, and 16b protrude toward the tube axis side along the front surface of the box-shaped portion 4, that is, so as to be parallel to each other in a plane perpendicular to the tube axis.

The vertical deflection coil 1 generates a vertical deflection magnetic field distorted in a barrel shape, and the horizontal deflection coil generates a horizontal deflection magnetic field distorted in a pincushion shape. 17, and this leakage magnetic field is picked up by the main surface portions 8, 9 of the first and second magnetic pieces 6, 7, resulting in an auxiliary vertical deflection with a pincushion-shaped distribution shown by solid line arrows in FIG. The magnetic field is applied to the four tongues 10&, 1
0b.

11a and 11b on the electron gun side, thereby reducing the occurrence of convergence coma and coma distortion of the beam spot.

The main surface portions 8, 9 and the third. Fourth tongue-shaped portion 15+
L, 15b, 162L, and 16b act as yokes for the horizontal deflection magnetic field, as shown in FIG. 6, so that the horizontal deflection magnetic field is strengthened. In other words, an auxiliary horizontal deflection magnetic field with a pincushion-like distribution is generated on the electron gun side, and it is possible to suppress the decrease in horizontal deflection efficiency that conventionally occurred due to the attachment of a pair of magnetic pieces.

The degree to which the horizontal deflection efficiency is improved depends on the shape of the magnetic piece used, so the lengths of the third and fourth tongue portions 15&, 15b, 16&, 16b, etc. may be adjusted as appropriate. The distance indicated by d in FIG. 6 only needs to be greater than 0, and can be, for example, 4M.

In the embodiment shown in FIG.
a, 15b, 16a, 18k are not parallel to each other,
They are arranged in a square shape. Further, modifications such as inserting the third and fourth tongue-like parts into the box-like part 4 of the insulating frame 2 are also possible.

Effects of the Invention As described above, according to the present invention, coma distortion of convergence coma and beam hot can be reduced without reducing horizontal deflection efficiency by simply adding magnetic pieces at relatively low cost and with a simple configuration. It is possible to reduce the amount of damage and also to provide compatibility with conventional deflection yokes.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a deflection yoke embodying the present invention, Fig. 2 is a perspective view of a magnetic piece of the deflection yoke, Fig. 3 is a rear view of the deflection yoke, and Figs. 4 to 6 are the same. An explanatory diagram of the operation of the deflection yoke, FIG. 7 is a side sectional view of a magnetic piece according to another embodiment of the present invention, FIGS. 8 and 9 are diagrams showing distortion of horizontal and vertical deflection magnetic fields, and FIG. FIG. 11 is a diagram for explaining convergence coma caused by a conventional deflection yoke, and is a diagram showing coma distortion of a beam spot. 1... Vertical deflection coil, 2... Insulating frame, 6° 7... Magnetic piece. Name of agent: Patent attorney Toshio Nakao and 1 other person 1st
Figure tsb, 41st Disturbance Officer Figure 2 Figure 6 C, '1 4 Figure 5 Procedural Amendment September 19, 1988 Patent Application No. 79757 2 Name of Invention Deflection Yoke 3M Correct Relationship with qr persons who apply for patents Patent application Address of person
1006 Kadoma, Kadoma City, Osaka Prefecture Name (584)
Matsushita Electronics Co., Ltd. Representative Fujimoto
Husband 4th Director, 571 Address Matsushita Electric Industrial Co., Ltd., 1006 Oaza Kadoma, Kadoma City, Osaka Name (5971) Patent Attorney Toshio Nakao,
. (1 other person) [Contact phone number (Tokyo) 437-1121 Tokyo Legal Affairs Branch]
5. Subject of amendment 6. Contents of amendment We will amend Figure 2 of the drawing as shown in the attached sheet.

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. an insulating frame having a first and a second
The first and second magnetic pieces have a main surface portion that faces each other through a vertical axis and magnetically couples to leakage magnetic fields of horizontal deflection and vertical deflection, and an electron beam of this main surface portion. first and second tongue-like parts extending horizontally from above and below on the gun-side end surface and protruding toward the electron gun side along the outer surface of the cylindrical part to generate an auxiliary vertical deflection magnetic field distorted in a pincushion shape; third and fourth tongue-like parts that extend horizontally from the upper and lower sides of the end surface of the main surface part on the side opposite to the electron gun, protrude toward the tube axis side, and generate auxiliary horizontal deflection magnetic fields that are distorted in a pincushion shape, respectively. A deflection yoke characterized by: