JPH07162879A - Deflection yoke - Google Patents

Abstract

PURPOSE:To obtain a deflecting yoke provided with a correction device capable of adjusting a static convergence drift in the screen center part of a color picture tube display device. CONSTITUTION:Two pairs of four-pole coils 1a-1d, 1e-1h to adjust horizontal static convergence are connected in parallel by winding so as to generate a magnetic field in an opposite direction, respectively, and a variable resistor 3 to adjust current quantity on each coil is connected to the coils on one side, and the DC is supplied between other terminals of the four-pole coils connected to the midpoint of the resistor in parallel. Also, two pairs of twopole coils 2a-2b, 2c-2d to adjust vertical static convergence are connected in parallel by winding so as to generate the magnetic field in the opposite direction, respectively, and a variable resistor 4 to adjust the current quantity on each coil is connected to the coils on one side. The DC is supplied between the other terminals connected to the midpoint of the resistor, and the coils are arranged on the electron gun side of the deflecting yoke.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke mounted on a color picture tube having an in-line type electron gun.

[0002]

2. Description of the Related Art Generally, in a color picture tube having an in-line type electron gun, not only the electron beams individually emitted from the three electron guns are focused on the fluorescent screen,
Focus on the same hole in the shadow mask (convergence)
It is necessary.

For this reason, the deflection yoke has a so-called self-convergence function in which the magnetic fields of the deflection yoke are made non-uniform so that the three electron beams are substantially coincident with each other on the entire screen of the color picture tube, and the deflection yoke operates. The non-existing portion, that is, the convergence at the center of the screen (hereinafter referred to as static convergence) is manually and optimally adjusted by a static convergence adjusting magnet provided near the electron gun of the color picture tube.

The deflection yoke and static convergence adjusting magnet for such an in-line type color picture tube are conventionally constructed and mounted as shown in FIG. That is, this deflection yoke is called a saddle type, and has a saddle type horizontal deflection coil (not shown) inside the funnel-shaped insulating frame 5, and a saddle type vertical deflection coil 7 inside the ferrite core 6. have. The static convergence adjusting magnet has a 4-pole magnet 8 for adjusting the side beams (R and B) and a 6-pole magnet 9 for adjusting the center beam (G).

[0005]

However, even if the deflection yoke having the above-mentioned configuration is adjusted so that the entire screen has a good convergence, the color picture tube shadow mask is domed, and the temperature rises in the vicinity of the electron gun causes the electron lens to move. Due to various factors such as the influence, the static convergence is deviated as shown in FIG. 4, which disturbs the convergence of the entire screen and significantly deteriorates the quality. Since the deviation of the static convergence changes with time, even if the optimum adjustment is made at the time of ITC adjustment, the convergence changes with the passage of time after the power is turned on when the product is used by the user after shipment. Cause a malfunction.

The present invention solves the above-mentioned conventional problems,
An object of the present invention is to provide a deflection yoke for an in-line type color picture tube which has good convergence characteristics.

[0007]

In order to solve the above problems, the present invention provides two sets of four-pole coils for adjusting the horizontal static convergence, which are wound so as to generate opposite magnetic fields in parallel. Connect a variable resistor for adjusting the amount of current to each coil to one end of the parallel circuit, and supply a DC current between the midpoint of the variable resistor and the other end of the four-pole coil connected in parallel. In addition, two sets of two-pole coils for adjusting vertical static convergence, which are wound so as to generate opposite magnetic fields, are connected in parallel, and the current to each coil is connected to one end of the parallel circuit. A variable resistor for adjusting the amount is connected, and a direct current is supplied between the other ends of the two-pole coils connected in parallel with the middle point of the variable resistor, and these coils are arranged on the electron gun side of the deflection yoke. You Configuration to.

[0008]

In the above structure, the optimum convergence can be obtained by adjusting the current flowing through each coil by the variable resistance according to the deviation amount of the static convergence.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a circuit diagram of the static convergence correction in the deflection yoke of the present invention, and FIG. 2 shows an external view of the deflection yoke. As shown in FIG. 1, the coils for correcting the horizontal static convergence are 1a, 1b, 1
With 8 coils of c, 1d, 1e, 1f, 1g, 1h,
4a of 1a-1d are connected in series, and 1e-
Four coils of 1 h are connected in series and each is connected in parallel. The coils for correcting vertical static convergence are four coils 2a, 2b, 2c, and 2d.
The coils 2a and 2b are connected in series, the coils 2c and 2d are connected in series, and each of them is connected in parallel.

Direct currents are supplied to the respective correction coils from the set side, and variable resistors 3 and 4 are provided to adjust the correction direction and the correction amount, respectively. Specifically, the variable resistor 3 is connected to one end of the parallel circuit of the coils 1a to 1d and 1e to 1h, and power is supplied between the midpoint of the variable resistor 3 and the other end of the parallel circuit. Also variable resistor 4
Is connected to one end of the parallel circuit of the coils 2a to 2b and 2c to 2d, and supplies power between the midpoint of the variable resistor 4 and the other end of the parallel circuit.

Each of the coils 1a to 1h and 2a to 2d.
2 are arranged as shown in FIG. 2, that is, when the deflection yoke is mounted on a color picture tube having three electron guns arranged in-line, two sets of coils 1a to 1h for correcting horizontal static convergence and Two sets of coils for compensating vertical static convergence 2
a to 2d are located on the small-diameter opening end side of the deflection yoke body.

In the case of this embodiment, the horizontal static convergence is corrected by adjusting the magnetic field generated by the coils 1a to 1d shown in FIG. 5 and the magnetic field generated by the coils 1e to 1h shown in FIG. This can be done by That is, when the currents flowing in the coils 1a to 1d and the currents flowing in the coils 1e to 1h are made equal by the variable resistor 3, the generated magnetic fields cancel each other out, and there is no correction effect. Coil 1 with variable resistor 3
When the current flowing in a to 1d is made larger than the current flowing in the coils 1e to 1h, Red moves to the right with respect to Blue. That is, Re of horizontal static convergence
d The miscon on the left can be corrected. If the variable resistor 3 causes the current flowing through the coils 1e to 1h to be larger than the current flowing through the coils 1a to 1d, the above-described reverse correction can be performed.

The vertical static convergence correction is performed by using the magnetic fields generated in the coils 2a and 2b shown in FIG.
This can be done by adjusting the magnetic field generated by the coils 2c and 2d shown in FIG.
That is, if the variable resistors 4 make the currents flowing through the coils 2a and 2b equal, the generated magnetic fields cancel each other out, and there is no correction effect. Coil 2 with variable resistor 4
When the current flowing in a and 2b is made larger than the current flowing in the coils 2c and 2d, Red moves downward with respect to Blue. That is, Re of vertical static convergence
Miscon on d can be corrected. Further, if the variable resistor 4 causes the current flowing through the coils 2c and 2d to be larger than the current flowing through the coils 2a and 2b, it is possible to perform the opposite correction.

In this embodiment, the variable resistor is used for adjusting the current to the coil, but an arithmetic circuit may be adopted to automatically supply a current corresponding to the time lag of static convergence. .

[0015]

As is apparent from the description of the above embodiment, according to the present invention, the deviation of static convergence, which has been a problem in the past, can be easily corrected on the user side, and the chassis side circuit can be used. It is possible to automatically control the correction current to improve the static convergence drift due to various influences, and to realize a deflection yoke for an in-line type color picture tube having good convergence characteristics.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a main part of a deflection yoke according to an embodiment of the present invention.

FIG. 2 is a rear perspective view of a deflection yoke according to an embodiment of the present invention.

FIG. 3 is a side view showing a conventional deflection yoke for an in-line type color picture tube and a static convergence adjusting magnet.

FIG. 4 is an explanatory diagram showing an example of deviation of static convergence.

FIG. 5 is an explanatory diagram for explaining the operation of a coil for horizontal static convergence correction.

FIG. 6 is an explanatory diagram for explaining the operation of a coil for horizontal static convergence correction.

FIG. 7 is an explanatory diagram for explaining the operation of a coil for vertical static convergence correction.

FIG. 8 is an explanatory diagram illustrating the operation of a coil for vertical static convergence correction.

[Explanation of symbols]

1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h Horizontal static convergence correction coils 2a, 2b, 2c, 2d Vertical static convergence correction coils 3, 4 Variable resistance

Claims (2)

[Claims] 1. A deflection yoke mounted on a color picture tube having three electron guns arranged inline, the deflection yoke main body comprising a pair of horizontal deflection coils and a pair of vertical deflection coils. On the side, there are at least two sets of coils for correcting horizontal static convergence and at least two sets of coils for correcting vertical static convergence, and the four coils for horizontal static convergence correction are connected in series. Two sets of coils are connected in parallel, a current adjusting means is connected to one end thereof, and a DC current is supplied between the current adjusting means and the other end of the horizontal static convergence correction coil connected in parallel. In addition, two sets of coils in which the two coils for vertical static convergence correction are connected in series are used. A parallel connection is made, a current adjusting means is connected to one end of the parallel adjusting means, and a direct current is supplied between the current adjusting means and the other end of the vertical static convergence correction coil connected in parallel. And deflection yoke. 2. The deflection yoke according to claim 1, wherein the current adjusting means comprises a variable resistor.