JPH07161555A - Fly-back transformer - Google Patents

Abstract

PURPOSE:To provide a fly-back transformer capable of reducing required material cost and rationalizing a mounting working process and having a ring core for a noise countermeasure. CONSTITUTION:In a fly-back transformer, in which a bobbin assembly, in which a high-voltage bobbin, on which a high-voltage output winding is wound, is inserted into the outside of a low-voltage bobbin, on which an input winding and a low-voltage output winding are wound, is incorported into a resin case and which has a focus pack 14, on which a rheostat for adjusting the focus voltage of a CRT and screen voltage is installed, a ring core 16 for a noise countermeasure, in which the focus lead and screen lead 15 of the focus pack are penetrated, is fixed onto the focus pack 14.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a flyback transformer.

[0002]

2. Description of the Related Art In a cathode ray tube (CRT) such as a television receiver or a display device, various voltages from low voltage to high voltage are required. Therefore, 100V to 150V produced by a power supply circuit is input to the primary side. However, a flyback transformer is used which is configured to obtain a low voltage output voltage of about 10V to 200V from the tertiary side and a high voltage output voltage of about 25KV to 30KV from the secondary side.

In a laminated winding type flyback transformer, an input (primary) winding and a low-voltage (tertiary) output winding are wound on a low-voltage bobbin, and a high-voltage (secondary) output winding is wound on a high-voltage bobbin, and a low-voltage bobbin. A high-pressure bobbin is fitted on the outside of the to form a bobbin assembly. A plurality of diodes are connected between the winding start end and the winding end end of each layer winding of the high voltage output winding wound on the high voltage bobbin. The final high voltage terminal of the high voltage output winding is connected to the anode terminal of the cathode ray tube. The flyback transformer is required to have improved performance for various purposes. Therefore, for example, a high-voltage capacitor (top C) and a high-voltage resistor (top R) are combined and built in. These parts are collectively housed in a resin case, and filled with an epoxy impregnated resin in order to ensure electrical insulation between these parts and the outside.

In order to realize a high resolution, a cathode ray tube of a double focus type and a double screen type is mainly used as a cathode ray tube for a display monitor in order to realize high resolution. A focus pack is attached to the resin case of the flyback transformer in order to adjust the focus voltage and screen voltage of the cathode ray tube.

[0005]

The windings, resistors, diodes, etc. in the flyback transformer described above generate a leakage magnetic field to the outside. This leakage magnetic field is a problem because it gives noise interference (EMI) to various electric devices such as screens of cathode ray tubes.

FIG. 3 is a front view of a flyback transformer having a conventional ring core for noise suppression.

In the flyback transformer 1 of FIG. 3,
The bobbin assembly 2, the top C / top R composite 3, and the focus pack 4 are enclosed in the same resin case. The focus pack 4 includes a focus variable resistor and a screen variable resistor, and further includes a resistance pattern printed on a circuit board and a slider for sliding the resistance pattern to adjust the resistance value. . Focus pack 4
The focus lead and the screen lead 5 are led out from and reach the neck portion of the cathode ray tube. A ring core 6 for noise suppression is attached to the focus pack 4. Therefore, the impedance around this becomes small and the noise falls to the ground, so that the noise trouble can be eliminated. .

Conventionally, the mounting work of the noise countermeasure ring core 6 has been performed in the following procedure. (1) The focus lead and the screen lead 5 are bundled. (2) The heat-shrinkable tube 7 is covered on the defined portions of the bundled focus lead and screen lead 5 so as not to damage the focus lead and screen lead 5. (3) One end of the heat-shrinkable tube 7 is fixed to the focus lead and the screen lead 5 with the binder 8, the ring core 6 is passed through the focus lead and the screen lead 5, and then the other end of the heat-shrinkable tube 7 is fixed to the binder 8. Then, the ring core 6 is positioned.

The conventional method of mounting the ring core 6 for noise suppression has the following drawbacks. (1) It cannot be automated because it can only be done manually. (2) The number of work steps increases. (3) The heat shrinkable tube 7 and two binders 8 are required. (4) Therefore, a lot of materials and a long working time are required,
High cost.

The present invention has been made in view of the above points, and an object of the present invention is to provide a flyback transformer having a noise-preventing ring core which can reduce the required material cost and rationalize the mounting work process. To do.

[0011]

In order to solve the above problems, the present invention inserts a high voltage bobbin wound with a high voltage output winding outside a low voltage bobbin wound with an input winding and a low voltage output winding. Bobbin assembly built in a resin case
In a flyback transformer having a focus pack provided with a variable resistor for adjusting the focus voltage and the screen voltage, the ring lead for noise suppression through which the focus lead and the screen lead of the focus pack are fixed to the focus pack. Is characterized by.

[0012]

Since the ring core for noise suppression is fixed to the focus pack, the mounting work can be simplified, the material cost can be reduced, and the mounting work process can be automated.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings.

FIG. 1 is a front view of the flyback transformer of the present invention.

In the flyback transformer 11 of FIG. 1, a bobbin assembly 12 and a top C / top R composite 13 are provided.
The focus pack 14 is enclosed in the same resin case. Three focus leads and screen lead 15 from the upper wall of the case of the focus pack 14
And the doughnut-shaped ceramic ring core 16 at the outlets of the focus pack 14
It is fitted and fixed to a mounting member 19 provided on the case. The focus lead and the screen lead 15 are respectively passed through these ring cores 16. The mounting member 19 may be formed integrally with the case of the focus pack 14 or may be a suitable member separate from the focus pack 14. Further, the ring core 16 itself may be integrally molded with the case of the focus pack 14.

FIG. 2 is a front view of another embodiment of the flyback transformer of the present invention.

In the flyback transformer 21 of FIG. 2, a bobbin assembly 22 and a top C / top R composite 23 are provided.
The focus pack 24 is enclosed in the same resin case. Three focus leads and screen lead 25 from the bottom of the case of the focus pack 24
Has been derived. One hollow cylindrical ring core 26
Is a mounting member 29 provided on the side wall of the focus pack 24.
It is fitted and fixed to. The mounting member 29 is integrally molded with the case of the focus pack 24, or is a suitable member separate from the focus pack 24. The three focus leads and the screen lead 25 are bundled and passed through the center hole of the ring core 26.

In the above embodiment, the focus leads of the flyback transformers 11 and 21 and the screen leads 15 and 25 are passed through the ring cores 16 and 26, so that the leakage magnetic field to the outside is prevented from occurring and noise is prevented. be able to.

[0019]

As described above, in the flyback transformer of the present invention, since the ring core for noise suppression through the focus lead and the screen lead is fixed to the case of the focus pack, these leads may be damaged. Absent. Further, since the ring core can be fixed only by fitting it in the case of the focus pack, the processing time and the processing process can be shortened, and the working process can be automated. Further, the material cost and the processing cost are reduced as compared with the conventional one.

[Brief description of drawings]

FIG. 1 is a front view of a flyback transformer of the present invention.

FIG. 2 is a front view of another embodiment of the flyback transformer of the present invention.

FIG. 3 is a front view of a flyback transformer including a conventional noise countermeasure ring core.

[Explanation of symbols]

 11 flyback transformer 12 bobbin assembly 13 top C / top R complex 14 focus pack 15 focus lead and screen lead 16 ring core 19 mounting member 21 flyback transformer 22 bobbin assembly 23 top C / top R complex 24 focus pack 25 focus lead and screen lead 26 ring core 29 mounting member

Claims (1)

[Claims] 1. A bobbin assembly in which a high-voltage bobbin wound with a high-voltage output winding is fitted outside a low-voltage bobbin wound with an input winding and a low-voltage output winding is incorporated in a resin case, and a CR is installed.
In a flyback transformer having a focus pack provided with a variable resistor for adjusting the focus voltage of T and the screen voltage, a ring core for noise suppression through which the focus lead and the screen lead of the focus pack penetrate is fixed to the focus pack. This is a flyback transformer.