JPH03184312A - Converter transformer - Google Patents

Abstract

PURPOSE:To lower a temperature rise, to improve efficiency and to enable miniaturization by flattening a part manufactured by spirally winding a member prepared by forming a plurality of slits in the longitudinal direction to one surface of an insulating sheet and dividing the sheet into a plurality of band- shaped metallic foils and using the flattened part as an internal coil. CONSTITUTION:A part manufactured by flattening a member prepared by spirally winding a member obtained by forming a plurality of slits 13 in the longitudinal direction to one part or the whole of the side wound on the innermost side on one surface of an insulating sheet 12 and dividing the sheet into a plurality of band-shaped metallic foils 14 is wound on a coil bobbin 11 and employed as an internal coil 16, an external coil 17 is wound on the outer circumference of the internal coil 16, and a magnetic core 20, to which a gap is formed, is assembled to the butting section of a magnetic leg 18 inserted into the coil bobbin 11 in the coil section. Accordingly, eddy currents generated in the metallic foil coil are reduced by leakage flux generated in the magnetic gap section of the magnetic core, eddy current loss can be inhibited at a low value, and an effect on the coil of the leakage flux of the magnetic gap is dispersed and levelled, thus preventing circulating currents and local heat generation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a converter transformer used in consumer or industrial electronic equipment.

Conventional technology A conventional converter transformer of this type is shown in Fig. 9.

The structure was as shown in FIGS. 10a and 10b. 1. As shown in FIGS. 9 and 10 a and b, an insulating film 2 and a band-shaped metal foil 3 are wound around a coil bobbin 1 in an overlapping manner, and a magnetic gap is formed at the abutting part of the magnetic leg 4 inserted into this coil part. 6
It was constructed by incorporating a magnetic core 5 that forms a.

Problems to be Solved by the Invention In such a conventional configuration, when the converter transformer is operated at a high frequency, leakage magnetic flux 7 is generated in the magnetic gap 60 portion of the magnetic core 6 and interlinks with the strip metal foil 3, causing a large eddy current to flow. However, the loss increases the temperature of the converter transformer, and the efficiency also deteriorates, making it difficult to miniaturize the converter transformer.

The present invention solves the above-mentioned conventional problems, and aims to reduce the temperature rise of the converter transformer, improve efficiency, and reduce the size of the converter transformer.

Means for Solving the Problems In order to solve the above problems, the present invention provides a coil bobbin with:
Multiple slits are formed in the length direction on part or all of the innermost side of one side of an insulating sheet, dividing it into multiple strips of metal foil, which are then wound in a spiral shape. A magnetic core is formed by winding a flattened core to form an inner coil, winding an outer coil around the outer periphery of the inner coil, and forming a magnetic gap at the abutting portion of the magnetic legs that fit into the coil bobbin. It is configured to incorporate.

Effect With this configuration, the eddy current generated in the metal foil coil due to the leakage magnetic flux generated in the magnetic gap of the magnetic core is blocked by the multiple slits, and the eddy current product during high frequency operation can be suppressed to a low level. In addition, by spirally winding and flattening, the influence of leakage magnetic flux from the magnetic gap on the coil can be dispersed and averaged, circulating current and heat generation at the poles can be prevented, and the temperature rise of the transformer can be lowered. The efficiency of the converter transformer can be improved and the size can be reduced.

Example An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 to 3, 11 is a coil bobbin, and a plurality of slits 13 are formed on one side of an insulating sheet 12 to divide the coil bobbin 11 into a plurality of strip-shaped metal foils 14, which are then spirally wound. , and an insulating film 15 is layered and wound to form the inner coil 16 shown in FIG. 3. An outer coil 17 is wound around the outer periphery of this inner coil 16, and a coil bobbin 11 is wound around this coil portion.
There is a magnetic gear knob 19 at the abutting part of the magnetic leg 18 that folds inside.
The structure incorporates a magnetic core 2o in which a magnetic core 2o is formed.

The inner coil 16 will be specifically explained using FIGS. 4 and 5. In FIGS. 4a and 4b, a plurality of slits 13 are formed on one side of an insulating sheet 12 to divide it into a plurality of strip-shaped metal foils 14. The inner coil 16 is a spirally wound coil as shown in FIGS. 6 and 6, which is then flattened. In Fig. 6, slits 13 are formed in the entire area from the beginning S to the end F, and in Fig. 6, the slits 13 are formed in a part from the beginning S towards the end fiF. FIG. 7 IL-O shows a cross section of the converter transformer, and FIG. 7a shows the slit 13 shown in FIG. It is constructed of a coil formed by winding a band-shaped metal foil 14 in a spiral shape and flattening it. As shown in FIG. 7, the inner coil 16 is a coil made by spirally winding and flattening the band-shaped metal foil 14 in which the slit 13 shown in FIG. 51 or FIG. Alternatively, it is constructed using stranded wire. Figure 7C shows the inner coil 1
Reference numeral 6 denotes a coil obtained by spirally winding and flattening a band-shaped metal foil 14 with a slit 13 shown in FIG. 5 or 6, and the outer coil 17 is constructed using the band-shaped metal foil. .

With this configuration, the eddy current generated in the inner coil 16 due to the leakage magnetic flux 21 generated from the magnetic gap 19 of the magnetic core 20 is blocked by the plurality of slits 13, as shown in FIG. Compared to technology, at an operating frequency of about 50 KHz, the equivalent series resistance is about 20~
By spirally winding the band-shaped metal foil 14 with the slits 13 formed therein as shown in FIG. By dispersing and averaging the effects of
It can be reduced to 0% and efficiency can also be improved.

Effects of the Invention As described above, according to the present invention, a plurality of slits are formed in the length direction on one side of an insulating sheet to divide it into a plurality of strip metal foils, which are then spirally wound. By flattening the coil, loss due to eddy current generated in the inner coil can be reduced by 20 to 60 yen, and residual heat generation at the extremes can be prevented, reducing the temperature rise of the converter transformer by 60 yen.
-20, the conversion efficiency of the converter transformer is improved, miniaturization is possible, and it is excellent in terms of quality and cost, and has great industrial value.

[Brief explanation of drawings]

Fig. 1 is an exploded perspective view showing one embodiment of the converter transformer of the present invention, Fig. 2 is the same perspective view, Fig. 3 is a schematic diagram of the winding structure of the converter transformer, and Figs. 4 a and b are the same. A plan view and a cross-sectional view showing the structure in which the inner coil used in the converter transformer is divided into strip metal foils, FIG.
Figures a and b are plan views of the spirally wound and flattened inner coil, Figures 7a-c are cross-sectional views showing examples of coil combinations of the converter transformer, and Figure 8 is a plan view of the flattened inner coil of the converter transformer. FIG. 9 is an exploded perspective view of a conventional converter transformer; FIG. 10a is a cross-sectional view of the same; FIG. FIG. 3 is a cross-sectional view showing magnetic flux. 12... Insulating sheet, 13... Slit, 14... Strip metal foil, 15... Insulating film, 16... Inner coil, 17・・・・・・
...Outer coil, 19...Magnetic gap, 20...Magnetic core, 21...Leakage magnetic flux.

Claims (1)

[Claims] A coil bobbin is spirally wound with multiple slits formed in the length direction on a part or the whole of the innermost side of an insulating sheet, which is divided into multiple strips of metal foil. This is then flattened and wound to form an inner coil, an outer coil is wound around the outer periphery of this inner coil, and a magnetic core is formed in this coil part with a gap formed at the abutting part of the magnetic legs that fit into the coil bobbin. Built-in converter transformer.