JPH0897061A - Flyback transformer equipment - Google Patents

Abstract

(57) [Summary] [Purpose] To realize the same output with the same insulation potential difference while reducing the number of layers and diodes in the secondary winding. [Structure] The winding start portion and the winding end portion of the secondary coil 3 of the first layer having the number of windings N are respectively placed at the winding center portion and the winding end portion of the secondary coil 4 of the second layer having the number of windings 2N. Position and winding number 2
The winding start portion and winding end portion of the secondary coil 5 of the third layer of N are
The winding start portion and the winding end portion of the second layer coil 4 are positioned respectively, and the winding start portion and the winding end portion of the fourth layer secondary coil 6 having the number of windings N are respectively set to the third layer secondary coil. The winding start portion and the winding center portion of No. 5 are wound and wound, and the diodes 7a, 7b, and 7c are inserted and connected in the forward direction between the coils, and the winding number N
About 6 times the output voltage of the positive induced pulse voltage
Obtained with the same interlayer insulation voltage as the 6-layer 6-diode configuration. The number of winding layers does not change.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flyback transformer device used in a television receiver or a display monitor device.

[0002]

2. Description of the Related Art In recent years, a secondary coil of a flyback transformer device is composed of laminated layers of 5 to 7 layers, and 5 to 7 rectifying diodes are used, which is the same as the number of layers.

A conventional flyback transformer device will be described below with reference to the drawings. FIG. 3 is a circuit diagram showing the configuration of a conventional flyback transformer device. In the figure, 1 is a primary coil, 2 is a magnetic core, 7 is a rectifying diode, 11a to 11f are secondary coils, respectively.
Reference numeral 2 is a flyback transformer, COL terminal is a collector terminal to which the collector of a transistor which is a switching element is connected, ABL terminal is an automatic brightness adjustment input terminal, and + B terminal is a power supply terminal to which a power supply is connected. FIG. 4 is a sectional view showing the structure of the secondary coil of the flyback transformer 12. In the figure, 9 is an insulating film, 10 is a bobbin for secondary coil winding, and 11 is a 6-layer laminated winding secondary coil.

The operation of the above configuration will be described. 1
When a positive pulse is applied to the collector terminal of the secondary coil 1, a positive pulse and a negative pulse are induced in the coils of each layer of the secondary coil 11 corresponding to rising and falling of the pulse. Now, assuming that the number of turns in each layer is the same and the pulse voltage induced in each layer is V2, the positive pulse in each layer is output to the output terminal 13 via each diode 7.
By outputting from, the voltage is almost 6V in case of 6 layers.
A DC voltage of 2 can be obtained. Also, the induced negative pulse is blocked by the diode 7. In this operation, assuming that the potential of the output terminal 13 is held at 6V2, each diode is turned off at the timing when the peak of the positive induced pulse has passed, and the coils of each layer are separated from each other. Since the voltage induced in the secondary coil is a fluctuating voltage due to a change in magnetic flux, the average potential of the coil not connected to DC does not change before and after the diode is turned on and off.

Considering the DC potential of each layer from this, the winding start portion of the coil 11a at the lowermost end (which is now the coil of the first layer) is DC 0V.
Since it is connected to the potential (assuming ABL level = 0V), the winding start portion is the potential fixed point, and the potential at the winding end portion changes to V2 with respect to the positive induced pulse. Next 2
With respect to the coil 11b of the layer, the potential at the winding end of the coil 11a of the layer 1 changes to + V2 as described above with respect to the positive induced pulse, and the diode 7a is turned on at + V2. , The potential at the winding start portion becomes + V2 when the diode 7a is on, and at that time, + V2 is applied to the coil.
Since the voltage of V2 is generated, the potential at the end of winding is +
It becomes 2V2. Therefore, when the diode 7b is turned on, + V2 is obtained at the winding start portion and + 2V2 at the winding end portion, and the average potential is 1.5V2. Since this coil is not connected in direct current, the average potential must be 1.5V2 even when the diodes 7a and 7b are off, and the potential of the winding start portion is + V2 and the winding end portion with respect to the negative induced pulse. Potential of + 2V2. Therefore, the potential fixed point of this coil is at the center of the coil, and its potential is 1.5V2.
In positive induced pulse, the potential at the beginning of winding is -0.5V
Relative change by 2 and winding end changes by + 0.5V2.

Other coils 11c, 11d, 11e, 11
Similarly, for f, there is a voltage fixed point at the center of the coil, and their potentials are 2.5V2, 3.5V2, and
4.5V2 and 5.5V2, and for those fixed point potentials, in the positive induced pulse, the winding start portion is -0.5V2.
Relative change, and the end of winding changes relative by + 0.5V2. The pulse waveform shown in FIG. 4 shows the distribution of the potential corresponding to the positive induced pulse in each layer. The pulse waveform for the negative induced pulse is omitted. As can be seen from the figure, the coil 11a of the first layer has a potential fixed point at the beginning of winding, whereas the coils of the second and higher layers have a potential fixed point at the center of the winding. One of the reasons for the multi-layer structure is that the potential difference between the layers can be made smaller as the number of layers is increased, so that the insulation reliability is improved and the breakdown voltage of the rectifying diode can be selected low. is there. In the above-mentioned conventional example, the maximum voltage difference with the winding of the adjacent layer to be considered for insulation is generated by the negative induced pulse, and its value is 2V.
Within 2

[0007]

In such a conventional flyback transformer device, in order to obtain a high voltage, the secondary coil is wound in multiple layers such as 6 layers, and the rectifying diode is used to end the winding of each laminated winding. Needs to have the same number of layers as, for example, 6 diodes, and
Since it has a multi-layer structure such as 6 layers, it reduces the number of winding steps,
It is disadvantageous for resource saving and size reduction of the flyback transformer by reducing the number of rectifying diodes.

The present invention solves the above problems, and an object of the present invention is to provide a flyback transformer device capable of reducing the number of winding layers and the number of diodes while ensuring the function and reliability.

[0009]

In order to achieve the above-mentioned object, the present invention is a flyback transformer in which a magnetic core has one coil and two coils wound around, and the secondary coil is divided into four layers. The number of windings of the coil of the first layer and the coil of the fourth layer is N, respectively, and the number of windings of the coil of the second layer and the coil of the third layer is 2N, respectively. The winding start part and the winding end part are respectively located at the winding center part and the winding end part of the second layer coil, and the winding start part and the winding end part of the third layer coil are respectively wound on the second layer coil. Winding at the winding start portion and winding end portion of the coil, and winding at the winding start portion and winding end portion of the fourth layer at the winding start portion and center portion of the third layer coil, respectively. Between the winding end of the second coil and the winding start of the second coil, 2
A rectifying element is provided between the winding end of the third coil and the winding start of the third coil, and between the winding end of the third coil and the winding start of the fourth coil. Flyback transformer device which is inserted and connected in a direction to obtain a DC voltage between the winding start portion of the first layer and the winding end portion of the fourth layer which is about 6 times the pulse voltage per number of turns N. Is.

[0010]

According to the present invention, in the above structure, the same output voltage as that of the 6-layer 6-diode structure is generated for the positive induced pulse, and the winding potential of the secondary coil of each layer and the winding potential of the adjacent layer. The maximum potential difference is equal to that in the case of the 6-layer structure when the negative induced pulse is generated, and the same insulation characteristic is obtained.

[0011]

【Example】

(Embodiment 1) An embodiment of the flyback transformer device of the present invention will be described below with reference to the drawings. Figure 1
FIG. 3 is a circuit diagram showing the configuration of this embodiment. In the figure, 1
Is a primary coil, 2 is a magnetic core, 3 is a first layer secondary coil, 4 is a second layer secondary coil, 5 is a third layer coil, 6
Is a secondary coil of the fourth layer and is connected in series by rectifying diodes 7a to 7c. However,
No diode is provided in the secondary coil 6 of the fourth layer.
FIG. 2 is a cross-sectional view showing the structure of the laminated winding of each layer of the secondary coil. As shown in FIG. 2, the winding start portion of the first layer secondary coil 3 and the winding end portion of the fourth layer secondary coil 6 are
The secondary coil 4 of the second layer and the secondary coil 5 of the third layer are located at the center of the winding, and the secondary coils 3 and 2
The number of turns of the secondary coil 6 is equal to N2, and the number of turns of the secondary coil 4 and the secondary coil 5 is equal to twice N2.

The operation of the above configuration will be described. 1
When a positive pulse is generated at the collector terminal COL of the next coil 1, a positive pulse and a negative pulse are induced in each secondary coil corresponding to the rising and falling of the positive pulse. Let V2 be the positive and negative pulse voltages induced across the secondary coil 3 of the first layer and the secondary coil 6 of the fourth layer.
Positive and negative 2V2 pulses are induced at both ends of the secondary coil 4 of the layer and the secondary coil 5 of the third layer. Each of these positive pulses is a rectifying diode 7a, 7b, 7
It is output from the output terminal 13 via c, and a total DC voltage of 6V2 is obtained, and the same voltage as the conventional example is obtained.

Considering the potential of each coil, the winding start portion of the secondary coil 3 of the first layer is fixed to the potential 0V as described in the conventional example, so that the winding start portion is the potential fixed point. Yes, the potential at the end of winding is + V for positive induced pulses
Displaces to 2. The potential of the secondary coil 4 of the second layer is
When the diode is on with respect to the positive induced pulse, the winding start portion is V2 and the number of windings is doubled, so that the winding end portion is 3V2 and the average potential is 2V2. Further, since the average potential does not change with respect to the negative induced pulse, the winding start portion is 3V2 and the winding end portion is V2. Therefore,
The fixed point of the electric potential is at the center of the coil, and the electric potential is 2
When the positive induced pulse is V2, the potential at the beginning of the winding changes by -V2 and the potential at the end of the winding changes by + V2 relative to the potential 2V2 at the center of the winding. Similarly, with respect to the secondary coil 5 of the third layer, the potential immobility point is in the center of the winding and the potential is 4V2. Is -V2, and the potential at the end of winding changes relative to + V2. Further, in the secondary coil 6 of the fourth layer, the winding end portion is fixed to the potential of 6V2, so the potential fixed point is the winding end portion, and the potential 6V2 at the winding end portion is wound in the positive induced pulse. The potential at the beginning changes relative to -V2. The pulse waveforms shown in FIGS. 1 and 2 show the pulse voltage relative to the potential immobility point of each coil. The waveform for the negative induced pulse is omitted.

When the respective secondary coils having the above potentials are arranged as shown in FIG. 2, the maximum potential difference between the windings of the adjacent layers is 2V2 regardless of whether the induction pulse is positive or negative. On the other hand, in the case of the 6-layer structure shown in the conventional example, 1
A maximum potential difference 2V2 occurs between the two layers for a negative induction pulse. Therefore, even if the number of layers is reduced from 6 to 4, the maximum potential difference between layers can be suppressed to the same level as in the 6-layer structure, and reliability can be ensured. If the same output voltage of 6V2 is realized by a normal four-layer structure, the maximum potential difference between layers is 3V2, and the effect of this embodiment is very large. Furthermore, the number of diodes can be reduced to three instead of four, and the effect of reducing the number of parts is large.

As described above, according to the deflection yoke device of this embodiment, the number of turns of the secondary coil 3 of the first layer and the secondary coil 6 of the fourth layer is N2, and the secondary coil 4 of the second layer is used. And the number of turns of the secondary coil 5 of the third layer is 2N2, and the winding start portion of the secondary coil 3 of the first layer and the winding end portion of the secondary coil 6 of the fourth layer are
The secondary coils 4 and 5 of the second layer and the third layer are wound so as to be located in the central portion and the respective coils are connected in the forward direction by three diodes. The output voltage of the layer 6 diode configuration and the insulation reliability between the layers can be realized by the four layer 3 diode configuration, which is extremely effective in reducing the number of steps and the number of parts.

[0016]

As is apparent from the above description, according to the present invention, in a flyback transformer in which a magnetic core has one coil and two coils, the secondary coil is divided into four layers and wound. The number of turns of the coil of the first layer and the coil of the fourth layer are N, respectively, and the number of turns of the coil of the second layer and the coil of the third layer are 2N, respectively, and the winding start portion of the coil of the first layer The winding end and the winding end are respectively located at the winding center and winding end of the second layer coil, and the winding start and winding end of the third layer are wound respectively. And the winding end portion are wound, and the winding start portion and the winding end portion of the fourth layer are wound at the winding start portion and the center portion of the coil of the third layer, respectively, and the first layer coil is wound. Between the winding end of the coil and the winding start of the second layer coil and the winding end of the second layer coil The rectifying elements are inserted and connected in the forward direction between the winding start portion of the third layer and between the winding end portion of the third layer coil and the winding start portion of the fourth layer coil, respectively. Between the winding start part of the coil and the winding end part of the fourth layer,
By obtaining a DC voltage which is about 6 times the pulse voltage per number of turns N, the same output voltage and insulation reliability as those of the conventional structure using 6 layers of laminated winding and 6 diodes can be obtained. It can be realized with a configuration using layer windings and three diodes.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of an embodiment of a flyback transformer device of the present invention.

FIG. 2 is a sectional view showing the structure of a secondary winding of the embodiment.

FIG. 3 is a circuit diagram showing a configuration of a conventional flyback transformer device.

FIG. 4 is a sectional view showing a configuration of a secondary winding of a conventional flyback transformer device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Primary coil 2 Magnetic core 3 1st-layer secondary coil 4 2nd-layer secondary coil 5 3rd-layer secondary coil 6 4th-layer secondary coil 7a-7c Rectification diode 12 Flyback transformer apparatus

Claims (1)

[Claims] 1. A flyback transformer in which a primary coil and a secondary coil are wound around a magnetic core, the secondary coil is divided into four layers and wound, and a first layer coil and a fourth layer coil are wound. The number of turns of each coil is N, the number of turns of the coil of the second layer is 2N, and the number of turns of the coil of the first layer is 2N. Located at the center and end of the winding,
The winding start part and the winding end part of the coil of the second layer are respectively positioned at the winding start part and the winding end part of the coil of the second layer, and are wound 4
The winding start portion and the winding end portion of the first layer are wound at the winding start portion and the center portion of the third layer coil, respectively, and the winding end portion of the first layer coil and the winding start portion of the second layer coil are wound. Between the winding end portion of the second layer coil and the winding start portion of the third layer, and between the winding end portion of the third layer coil and the winding start portion of the fourth layer coil. , Rectifying elements are inserted and connected in the forward direction, and between the winding start portion of the first layer coil and the winding end portion of the fourth layer, about 6 pulse voltages per number N of turns are provided.
A flyback transformer device that doubles the DC voltage.