JPS602074A - flyback transformer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flyback transformer for supplying high voltage to a cathode ray tube anode of a television receiver.

Generally, in a flyback transformer, a predetermined high voltage is obtained by boosting the pulse voltage generated by the switching operation and the L and C resonant circuits using a high voltage fill, and rectifying it using a rectifier diode. , the pulse voltage is generated during the retrace period, but due to the distributed capacitance and leakage inductance, it becomes a high frequency much higher than the fundamental wave of the flyback pulse, which is superimposed on the pulse as ringing. Are known.

This linking energy then spreads to each part of the TV 992 circuit through capacitive coupling or electromagnetic coupling, and as a result, it appears as bright and dark vertical stripes on the screen of the cathode ray tube.
This causes inconveniences such as deterioration of tiI quality and unnecessary current flowing through the high-pressure fill, which causes temperature rise.To eliminate such inconveniences, that is, to obtain a flyback transformer that does not cause ringing. This is strongly desired from the viewpoint of obtaining good image quality characteristics and from the viewpoint of safety.

On the other hand, recently, as shown in FIG. 1, as a flyback transformer, a high-voltage filter 1 is formed into a plurality of (four in the drawing) winding sections 1a and 1b having approximately the same number of turns.

Divided into 1c and 1d, between each winding section 13 to 1d, and
A rectifier diode 2a is connected in series to the output side of the final winding section 1d.
, 2b, 2C, and 2d, and each winding section 13 to 1d of the high-voltage coil 1 is overlapped with the primary film 4 wound on the core 6 via the insulating layer S, so as to be sequentially concentric with the core 6. A structure formed by laminated and wound in a shape has been developed and put into practical use. In the case of such a configuration, since the coupling between each layer (winding sections 13 to 1d) of the high-voltage fill 1 is extremely good and there is no AC potential between each layer, ringing occurs between each winding section 1a to 1d. A loop is not formed to generate the ringing, and ringing occurs only between the winding section 1a on the starting end side (first layer) of the high voltage coil 1 and the primary coil 4.

Conventionally, in order to eliminate such ringing, a resistor 5 is connected in series between the winding section 1a on the starting end side of the high voltage coil 1 and the ground, as shown in FIG. It was made by consuming.

However, in such a configuration, the ringing energy is consumed by the resistor 5 and the ringing is attenuated, but at the same time, the current of the fundamental pulse of the flyback transformer flows through the resistor along with the harmonic number, and this fundamental pulse is also consumed. In addition, there is a possibility that the ringing energy will be concentrated in the resistor 5, causing the resistor 5 to generate heat. Met.

The present invention relates to a flyback transformer aimed at eliminating the above-mentioned drawbacks, and particularly relates to a flyback transformer having a configuration that consumes ringing energy generated in the flyback transformer without losing the fundamental pulse of the flyback transformer. It is something.

Hereinafter, one embodiment of the flyback transformer of the present invention will be described in detail with reference to the drawings. In FIG. 2, core 11
A primary film 12 is wound around the outer periphery of the secondary coil 12 in a wide manner, and a high voltage coil 13 is wound around the outer periphery of the secondary coil 12 with a substantially equal number of turns.
winding sections 13a, 13b, 13C, and 16d, and each winding section 13a to 13d is sequentially stacked concentrically with respect to the core 11 (-order film 12) via an insulating layer S. It is passed around. Rectifier diodes 14a and 14b are connected in series between each winding section 132 to 13d of the high-voltage filter 16 and on the output side of the final winding section 16d, respectively.
, 14c, and 14d are connected to obtain a high voltage output from the output end of the rectifier diode 14d. Here, among the winding sections 1.3a to 13d constituting the high voltage coil 13,
The number of turns approximately equal to the number of turns of the winding section 13a is applied to the starting end side where ringing occurs between the -secondary coil 12, that is, the winding section 13a that is wound on the innermost circumference adjacent to the -secondary coil 12. The ringing removing means 1 (,
C are connected in parallel, and the ringing removal means RC
The ringing removal coil 15 is wound on the core 11 on the inner periphery of the winding section 13a and sandwiched between the winding section 13a and the primary coil 12.

FIG. 6 shows another embodiment of the ringing removal means RC of the flyback transformer according to the present invention. A resistor 16 is connected in series to constitute a ringing removing means RC having a resistance value higher than the resistance value of the winding section 13a. −
+As described above, the resistor 16 is wound on the core 11 while being sandwiched between the winding section 13a and the primary coil 12, and the resistor 16 is either integrally (built-in) with the flybank transformer or separately (externally attached).

In a flyback transformer having such a configuration, the number of turns of each layer (winding sections 132 to 13d) of the high-voltage filter 16 is made approximately equal, and the layers are arranged concentrically with respect to the core 11 by overlapping the primary coil 12 wound around the filter 711. By laminating and winding it in a shape, the bond between each layer of the high-pressure filter 13 is extremely good, and there is no AcIfjL level between each layer.
A loop for causing ringing is not formed between each winding section 13a to 13d, and between the winding section 13a on the starting end side of the high-pressure filter 13 and the primary coil 12, a ringing removing means E, C is provided between the winding sections 13a to 13d. A ringing removal coil 15 having approximately the same number of turns as 13a is wound in winding section 1.
3a, the ringing removal coil 15 has the same voltage waveform as the winding section 13a, and the winding section 13a and the ringing removal coil 1
Since no current flows through the distributed capacitance between the winding section 13a and the ringing removal filter 15, no loop is formed between the winding section 13a and the ringing removal filter 15. Finally, a ringing loop is formed by the distributed capacitance between the ringing removal coil 15 constituting the ringing removal means RC and the primary coil 12, and ringing occurs. This ringing energy is consumed by the DC resistance component of the ringing removal coil 15, and the ringing is attenuated. Here, winding section 1 on the starting end side of the high voltage coil 13
3a and the current flowing through the ringing removal means R, C (IJ ringing removal coil 15) are determined by the resistance value of each coil. The resistance value of the ringing removal means RC is adjusted in advance to the resistance value of the winding section 15a by using a resistance wire, using a thin wire, or by connecting a resistor 16 in series to the ground side of the ringing removal coil 15. Since it is set high compared to
Ringing removal coil 15 (ringing removal means RC)
The current flowing through the winding section 1'3a is smaller than the current flowing through the winding section 1'3a, and as a result, most of the fundamental pulse current of the flyback transformer is not consumed and is lost because it flows through the winding section 13a. Therefore, almost no power loss occurs.

In addition, in one embodiment of the flyback transformer of the present invention, a high-voltage coil is divided into four winding sections having approximately the same number of turns. However, the number of divisions of the high-voltage fill is limited to the embodiment. The number of rectifying diodes can be increased or decreased according to the increase or decrease in the number of divided high-voltage coils.

Further, the winding shape of the high-voltage coil and the secondary coil is arbitrary, and for example, a sexy plain bobbin may be used to wind it in a cefsilane shape.

As described above, according to the flybank transformer of the present invention, a high-voltage coil is divided into a plurality of winding sections having approximately the same number of turns, and a rectifier diode is connected in series between each winding section and on the output side of the final winding section. In a flyback transformer in which each winding section is successively wound concentrically around a core around which the next coil is wound, at least one of the winding sections is connected to the winding section on the starting end side of the high-voltage fill. A ringing removing coil having a number of turns approximately equal to the number of turns and a ringing removing means having a resistance value higher than that of the winding section on the starting end side are connected in parallel, and the ringing removing coil of the ringing removing means is connected to the high voltage coil. The winding is arranged between the winding section on the starting end side and the primary coil, and the high voltage coil and the primary film are shielded by a ringing removal means, and a ringing loop is formed between the ringing removal coil and the primary film. is configured and ringing occurs, but the ringing energy is consumed by the resistance component of the ringing removal coil or the resistance component of the ringing removal coil and the resistance component of the resistor connected in series with the ringing removal coil and is efficiently attenuated. Finally, a flyback transformer with ringing removed can be obtained.

In addition, by placing a ringing removal coil with approximately the same number of turns as the winding section of the high-voltage coil between the winding section on the starting end side of the high-voltage coil and some of the coils, the ringing removal coil can be removed between each winding section of the high-voltage coil and There is no distributed capacitance between the winding section on the starting end side of the high-voltage filter and the ringing removal coil, and a ringing loop is never formed. The ringing loop that had occurred is moved between the ringing removal coil and a part of the film, so there is no need to provide ringing removal means for each winding section of the high voltage coil, and it is simply necessary to remove the ringing from the starting end of the high voltage coil. Ringing can be reliably removed simply by providing a ringing removing coil of the ringing removing means between the side winding section and some of the coils. Furthermore, by connecting a ringing removal means having a resistance value higher than the resistance value of the winding section in parallel to the winding section on the starting end side of the high voltage fill, most of the basic pulse current of the flyback transformer is transferred to the ringing removal means. The basic pulse of a flyback transformer is almost never lost, compared to a conventional high-voltage coil constructed by connecting a resistor in series with the winding section. Power loss is also extremely reduced. Here, it is possible to consider a method of shielding ringing by inserting a resistor connected in series to a plate-shaped conductor between a part of the coil and the high-voltage coil in the same way as a ringing removal coil. Compared to , the current flowing through the conductor is larger and the fundamental pulse loss is also larger. In addition, in the present invention, by configuring a part of the ringing removal means using a wound coil, the eddy current loss with respect to the fundamental pulse is reduced compared to a case where the ringing removal means is configured using a plate-shaped conductor. , fundamental pulse loss and power loss are also reduced.

In addition, as a method to flow only the basic pulse current, it is possible to connect a parallel circuit of a resistor and a coil in series to the starting end (low voltage end) of the high voltage coil, but in this case,
Since the resistor and coil are connected in series with the high voltage fill, this results in an increase in impedance to the basic pulse current and an increase in leakage inductance. In contrast, according to the configuration of the present invention, the ringing removal means is connected in parallel with the high-voltage coil, and there is no increase in impedance or leakage inductance with respect to the basic pulse current. On top of that,
Since the consumption of ringing energy is distributed throughout the ringing removal means, there is no concern that abnormal heat generation will occur on the circuit, and it is highly safe. As described above, according to the flyback transformer of the present invention, ringing can be removed with an extremely simple configuration, and good image quality characteristics can always be obtained, making it particularly effective as a high-performance flyback transformer. be.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional flyback transformer, FIG. 2 is a sectional view of a flyback transformer according to an embodiment of the present invention, and FIG. 3 is a configuration circuit diagram of another embodiment of the present invention. 11.: 17.12 -order coil, 16 high voltage coil, 13a to 13d...high voltage coil winding section, 16a.
・Starting end side winding section, 14a to 14d... Rectifier diode, R, C... Ringing removal means, 15 Ringing removal coil, 16-・Resistor, Patent applicant: Denki Acoustic Co., Ltd.

Claims (3)

[Claims] (1) Divide the high-voltage coil into multiple winding sections with approximately the same number of turns, connect rectifier diodes in series between each winding section and on the output side of the final winding section, and sequentially connect each of the winding sections. In a flyback transformer formed by laminated winding concentrically around a core around which a coil is wound, a ringing removal method having a winding section on the starting end side of the high voltage coil has a number of turns at least approximately equal to the number of turns of the winding section. Ringing removal means including a coil and having a higher resistance value than the resistance value of the winding section on the start end side are connected in parallel, and the ringing removal filter of the ringing removal means is connected to the winding section on the start end side of the high voltage fill. A flyback transformer characterized in that the winding is arranged between the primary coil and the primary coil. (2) The flyback transformer according to claim 1, characterized in that the ringing removal means is constituted only by a ringing removal coil having a resistance value higher than the resistance value of the winding section on the starting end side of the high voltage coil. (3) The flyback transformer according to claim 1, wherein the ringing removing means is comprised of a ringing removing coil and a resistor connected in series to the ground side of the ringing removing coil.