JP3531041B2 - Deflection yoke - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke installed in a color picture tube provided with an in-line type electron gun. 2. Description of the Related Art In recent years, high quality of images has been demanded in television receivers and OA equipment, and improvement of convergence characteristics has been an issue. Hereinafter, a conventional deflection yoke will be described. Generally, in a color picture tube having an in-line type electron gun, it is necessary that electron beams individually emitted from three electron guns converge on a phosphor screen and converge on the same hole of a shadow mask (convergence). is there. Therefore, a so-called self-convergence function is provided in which the three electron beams are made substantially coincident with each other in the entire portion of the color picture tube screen by making the magnetic field of the deflection yoke non-uniform. [0004] However, a higher definition is required for the display of a television receiver or an OA device for receiving a high-definition broadcast.
As the deflection frequency increases, it has been necessary to take measures to eliminate the inconsistency of the three electron beams on the screen, which has not been seen. As a countermeasure, as shown in FIG. 6, a pair of differential coils 21 are inserted into the horizontal deflection circuit, and this is caused by variations in windings and mounting positions of the horizontal deflection coils arranged above and below the color picture tube neck. cross misconvergence between side beams on the screen horizontal axis by asymmetric deflection magnetic field for correcting, further, a pair of correction coils Yoo
The unit 23 and a magnetic bias coil for adjusting the amount of current supplied thereto are inserted to correct the horizontal misconvergence XH between the side beams Rb and Bb around the screen horizontal axis as shown in FIG. ing. In such a conventional deflection yoke, the correction coil for preventing misconvergence does not contribute to the deflection of the electron beam. There are various problems.
In particular, in recent years, color display devices of the energy-saving type with greatly reduced power consumption have become mainstream, and the power consumption required of the deflection yoke is also high voltage 25K.
In V, the value has become very severe, that is, 13 mHA ² . For this reason, the deflection yoke is of a saddle type for both horizontal deflection and vertical deflection, and a saddle / saddle type having a structure surrounded by a ferrite core is mainly used. This saddle
Since the saddle type deflection yoke surrounds the deflection coil with a ferrite core, it has a feature that the external leakage magnetic field is small and the electron beam can be effectively deflected. When the misconvergence correction coil is inserted into the horizontal deflection circuit in this manner, power is consumed by the inductance of the correction coil. In particular, the XH misconvergence correction coil 23 shown in FIG. As a result, the inductance is large and the power loss is large. Therefore, the power consumption of the horizontal deflection circuit increases, which makes it difficult to save the power of the deflection yoke. Also,
When a correction coil is inserted in the horizontal deflection circuit, a striped ringing pattern generated at the left end of the screen at the start of horizontal deflection scanning as shown in FIG. An object of the present invention is to provide a deflection yoke which solves the above-mentioned problem, has low power consumption, and can correct misconvergence while suppressing occurrence of ringing. [0008] In order to achieve the above object, the present invention provides a core having a large-diameter opening surface and a small-diameter opening surface, and a pair of horizontal deflection members disposed inside the core. A deflection yoke for a color picture tube, comprising: a coil, a pair of vertical deflection coils, and a differential coil comprising a first coil and a second coil connected in series to the horizontal deflection coil and wound in the same direction on a common core. , An auxiliary coil wound around a rod-shaped core disposed near the outside of the differential coil and coupled to the magnetic flux of the differential coil, and rectifies a voltage induced in the auxiliary coil by a bridge-connected rectifying element. Move the rectifier circuit and the side beam concentration point
A set of four compensation coils connected in series for dynamic compensation and inside the tube
Set of four correction coils connected in series for movement correction
And one end of each set are connected in common, the other end is connected via a variable resistor and connected in parallel with each other, and the rectifying circuit is connected between the common connection point and the sliding point of the variable resistor. A deflection yoke for a color picture tube including an auxiliary magnetic flux generating circuit to which a rectified output is connected and supplied with current. According to the present invention, in the above configuration, the leakage magnetic field of the first coil and the second coil of the differential coil interlinks with the auxiliary coil to generate an induced voltage, and the bridge-connected rectifier circuit generates the induced voltage. The voltage is rectified to supply a current to the auxiliary magnetic flux generation circuit. The magnetic flux generated by the auxiliary magnetic flux generation circuit corrects horizontal misconvergence of the side beam around the horizontal axis of the screen. As in the prior art, it is not inserted in series to the horizontal deflection circuit correction coils constituting the auxiliary magnetic flux generating circuit. Embodiment 1 Hereinafter, an embodiment of a deflection yoke according to the present invention will be described with reference to the drawings. Figure 1 is a circuit diagram showing the configuration of this embodiment, an auxiliary magnetic flux generating circuit for correcting the horizontal misconvergence between the side beams in the periphery of the screen horizontal axis. The same components as those of the conventional example shown in FIG. 6 are denoted by the same reference numerals, and detailed description thereof will be omitted. In the figure, 2
2 generates an induced voltage magnetically coupled to the differential coil 21, power source and comprising an auxiliary coil for supplying a current to the correction coil unit 23, the resistor 24 connected to both ends of the auxiliary coils 22, 25 Is a variable resistor that adjusts the correction amount of the correction coil unit 23, and D1, D2, D3, and D4 are rectification diode bridges that rectify the voltage of the auxiliary coil 22 and supply current to the correction coil unit 23. The correction coil unit 23 includes a series connection of correction coils 23a, 23b, 23c, and 23d, and correction coils 23e, 23f,
23g and 23h are connected in parallel with each other via a variable resistor 25.
It is supplied with current by the diode bridge. The variable resistor 25 may be provided on the diodes D2 and D4. FIG. 2 is an external view showing the structure of this embodiment. The correction coil unit 23 is arranged as shown in the figure, and when the deflection yoke is mounted on a color picture tube having three electron guns arranged in-line, two correction coils 23a to 23c of the correction coil unit 23 are provided. 23h is located on the small diameter opening side of the deflection yoke body, the differential coil 21 is disposed in the deflection yoke vertical axis upper terminal plate 26, disposed an auxiliary coil 22 which is wound on the rod-shaped core is adjacent to the differential coil 21 Is done. In a horizontal deflection circuit, a horizontal deflection coil 2
0 is the first horizontal deflection coil 20a and the second horizontal deflection coil 2
0b and is connected in parallel via the first coil 21a and second coil 21b of the differential coil 21, a horizontal output stage of the terminal H ⁺ and H ^- horizontal deflection current is supplied is connected between the . As shown in FIG. 5, the differential coil 21 includes a first coil 21a wound around a rod-shaped core 21c in the same direction and a second coil 21a.
The core 21c is made of a coil 21b, and is movable in the axial direction as indicated by the arrow. The operation of the above configuration will be described.
FIG. 3 shows a magnetic field generated by the correction coils 23a to 23d and a direction in which RGB moves by the magnetic field. FIG. 4 shows a magnetic field generated by the correction coils 23e to 23h and a direction in which RGB moves by the magnetic field. FIG. As can be seen from FIGS. 3 and 4, the moving directions of the correction coils 23a to 23d and the correction coils 23e to 23e are different.
The directions of movement by 23h are opposite to each other.
Accordingly, the current value is changed by the variable resistor 25 between the intensity of the magnetic field generated by the correction coils 23a to 23d shown in FIG. 3 and the intensity of the magnetic field generated by the correction coils 23e to 23h shown in FIG. By adjusting
Corrects misconvergence of side beams around the horizontal axis of the screen. When a current flows through the horizontal deflection circuit through the differential coil 21, the leakage magnetic flux formed by the differential coil 21 links the auxiliary coil 22 to generate an induced voltage, and the induced voltage is applied to the diode bridges D1 to D4. Rectified by
Always the correction coil 23a → 23d and the correction coil 23
A current is supplied in the direction of e → 23h. At this time, the current flowing through the correction coils 23a to 23d and the correction coil 23h
When the variable resistor 25 is set so that the current flowing through .about.23e becomes equal, the generated magnetic fields cancel each other out and have no correction effect. When the current flowing through the correction coils 23a to 23d is set to be larger than the current flowing through the correction coils 23h to 23e, Red moves to the right with respect to Blue, that is, Red Left (XH) around the screen horizontal axis.
Misconvergence of the barrel pattern) can be corrected.
When the current flowing through the correction coils 23h to 23e is larger than the current flowing through the correction coils 23a to 23d, the reverse correction can be performed. Since the horizontal deflection current is zero at the center of the screen and on the vertical axis, the above correction is not performed. Also,
Even if the horizontal deflection direction changes, the direction of the leakage magnetic flux of the differential coil 21 linked to the auxiliary coil changes, and the direction of the induced current changes, the bridge coil rectification by the diodes D1 to D4 causes the correction coil unit 23 to operate. The direction of the current flowing through is always the same. In this embodiment, the differential coil 21 has 25 turns, the auxiliary coil 22 has 30 turns, and each correction coil has 20 turns.
Turn, the diode is a silicon diode (VF = 0.
7V), the resistance of the resistor 24 is 4.7Ω, and the correction amount is 0.3 m.
m was secured. In this embodiment, the auxiliary coil 2
2 is wound around the rod-shaped core adjacent to the differential coil 21, but may be wound coaxially around the differential coil 21, or may be wound around the differential coil 21.
Needless to say, the same effect can be obtained by winding the first coil 21a between the first coil 21a and the second coil 21b. As described above, according to the deflection yoke of the present embodiment, an induced voltage serving as a power supply is generated from the horizontal deflection current by the auxiliary coil coupled to the magnetic field of the differential coil connected in series with the horizontal deflection coil. Since the voltage is bridge-rectified and the current is supplied to the correction coil, the correction coil is not inserted in series with the deflection circuit, so that the loss of the deflection power is small and the ringing is generated. Thus, a deflection yoke that can correct misconvergence can be realized. As apparent from the above description, the present invention provides a core having a large-diameter opening surface and a small-diameter opening surface, a pair of horizontal deflection coils and a pair of horizontal deflection coils disposed inside the core. A deflection yoke for a color picture tube comprising: a vertical deflection coil; and a differential coil comprising a first coil and a second coil connected in series to the horizontal deflection coil and wound in the same direction on a common core. An auxiliary coil wound around a rod-shaped core disposed near the outside of the differential coil and coupled to the magnetic flux of the differential coil; and a rectifier circuit for rectifying a voltage induced in the auxiliary coil by a bridge-connected rectifying element. A set of four correction coils connected in series to move and correct the point of concentration of the side beam to the outside of the screen.
A pair of a set of four correction coils to be corrected connected in series is connected in parallel with one end of each set connected in common and the other end connected via a variable resistor, and the common connection point and the variable resistor are connected in parallel. And a supplementary magnetic flux generating circuit to which a current is supplied by connecting the rectified output of the rectifying circuit between the sliding point and the sliding point of the rectifying circuit, which is conventionally caused by inserting a misconvergence correction coil into the horizontal deflection circuit. Loss of deflection power, and the occurrence of ringing can be prevented,
A deflection yoke for an in-line type color picture tube having good convergence characteristics can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram showing a configuration of an embodiment of a deflection yoke according to the present invention. FIG. 2 is a rear view showing the configuration of the embodiment. FIG. 3 is a misconvergence in the embodiment. FIG. 4 is a schematic diagram illustrating the operation of a correction coil. FIG. 4 is a schematic diagram illustrating the operation of a misconvergence correction coil in the embodiment. FIG. 5 is a schematic diagram illustrating the configuration of a differential coil in the embodiment. FIG. 7 is a circuit diagram showing a misconvergence pattern around the horizontal axis of the screen. FIG. 8 is a pattern diagram showing a ringing pattern at the left end of the screen. [Description of References] 20 Horizontal deflection coil 21 Differential Coil 22 Auxiliary coil 23 Correction coil units 23a to 23h Correction coil 24 Resistor 25 Variable resistor 26 Terminal plate D1 to D4 Diode

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 9/28 H01J 29/76

Claims (1)

(57) [Claim 1] A core having a large-diameter opening surface and a small-diameter opening surface, a pair of horizontal deflection coils and a pair of vertical deflection coils disposed inside the core, A deflection yoke for a color picture tube, comprising a differential coil composed of a first coil and a second coil wound in the same direction on a common core and connected in series to a horizontal deflection coil, in the vicinity of the outside of the differential coil. An auxiliary coil wound around the disposed rod-shaped core and coupled to the magnetic flux of the differential coil; a rectifier circuit for rectifying a voltage induced in the auxiliary coil by a bridge-connected rectifier ; Move outside the tube surface
A set of four compensation coils connected in series for dynamic compensation and inside the tube
Set of four correction coils connected in series for movement correction
And one end of each set are connected in common, the other end is connected via a variable resistor and connected in parallel with each other, and the rectifying circuit is connected between the common connection point and the sliding point of the variable resistor. A deflection yoke for a color picture tube, comprising: an auxiliary magnetic flux generation circuit connected to a rectified output and supplied with current.