JPH0452976Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an interference wave blocking transformer used to remove noise in a high frequency range transmitted through a power supply line.

[Prior Art] When using information equipment, medical equipment, audio equipment, control equipment, etc., it is necessary to prevent circuit destruction or malfunction caused by noise transmitted through power lines. An interference wave blocking transformer was inserted between the equipment and the equipment to prevent noise from entering the equipment. In other words, in the above-mentioned interference wave blocking transformer, commercial frequency components are allowed to pass, high frequency components that are noise are allowed to pass, but high frequency components that are noise are blocked. It was necessary to reduce the amount to a level that would prevent the system from malfunctioning.

Conventionally, such a transformer has been constructed by winding a primary winding 2 and a secondary winding 3 in an overlapping manner around the center leg of an iron core 1 with low effective high frequency permeability, as shown in FIG. A conductive shielding plate 4 is placed between both windings 2 and 3.
Alternatively, as shown in FIG.
It is generally known that a conductive shielding plate 4 is disposed between the primary side and the secondary side to prevent noise from being transmitted from the primary side to the secondary side. Although not shown, the entire circumference of each of the windings 2 and 3 is coated with a good conductor to prevent noise from being transmitted due to electromagnetic radiation.

[Problems to be solved by the invention] However, in the case of the above transformer, the primary winding 2 and the secondary winding 3 are located on the same axis, so the magnetic coupling between the windings is strong, and therefore transformation is not possible. Although it has excellent functionality, noise is easily conducted, and the noise prevention effect is not sufficient. On the other hand, in the case of the above transformer, the primary winding 2 and the secondary winding 3 are arranged in parallel, so the magnetic coupling between the windings is weak, which reduces noise conduction and prevents noise. Although it is highly effective, the transformer function deteriorates, and in order to secure a predetermined rated capacity, the transformer has the disadvantage of being larger than the above-mentioned transformer. In this way, each transformer has its advantages and disadvantages.
Therefore, there has been a long-awaited development of an interference wave blocking transformer that is more effective in preventing noise than the above-mentioned transformers, is compact in size, and has a good transformation function.

Note that when the primary winding and secondary winding are arranged at right angles, the magnetic flux passing through the air (magnetic flux inducing noise)
It is already known that magnetic coupling is less likely to occur, and noise conduction can be significantly reduced (Japanese Patent Laid-Open No. 7912/1983). However, even if a transformer is manufactured in which a primary winding and a secondary winding are arranged on one yoke and leg of the iron core, the iron core will become magnetized during use.
As a result, ``beat'' was generated in the iron core, and this ``beat'' made it unusable.

This invention was developed based on the fact that if the primary winding and secondary winding are arranged at right angles to the iron core, noise conduction can be significantly reduced.
When winding the secondary winding and the secondary winding at right angles, at least one of the windings is wound separately on both legs of the core to prevent the entire core from becoming magnetized. It is possible to provide an interference wave isolation transformer that can be used without generating "beat" in the iron core, has a better noise isolation effect than the above transformers, is relatively small, and has a good transformation function. It is to do so.

[Means for Solving the Problems] That is, the present invention has a primary or secondary winding on at least one of the yoke parts of an iron core consisting of both leg parts and a yoke part connecting the two end parts. Either one of the windings is wound on the wire, and the winding portion of the other winding consisting of two identical winding portions is wound on both legs, and the one winding and the other winding are wound on both legs. A conductive shield plate is arranged between each winding portion of the winding.

[Function] With the above structure, for example, by setting one winding as the primary winding and the other winding as the secondary winding, the primary winding and the secondary winding can be arranged at right angles. Therefore, most of the magnetic flux generated by the low-frequency current flowing into the primary winding from the power line passes through the iron core and interlinks with the winding section of the secondary winding. As a result, an electromotive force is induced in the secondary winding due to mutual induction. On the other hand, the high-frequency current of the nozzle superimposed on the source wire also flows into the primary winding and generates magnetic flux, but this magnetic flux cannot pass through the iron core, which has a low effective high-frequency permeability. It is radiated into the air in the axial direction of the primary winding, and there is almost no interlinkage with the secondary winding. Furthermore, electromagnetic waves generated by the high-frequency current flowing into the primary winding, that is, lines of electric force, are radiated in a direction perpendicular to the axial direction of the primary winding, but due to the shielding plate, eddy current This means that it will be consumed as 100%, and will hardly reach the secondary winding side, and the above-mentioned shield plate will prevent capacitive coupling between each winding part of the primary and secondary windings. Therefore, the noise conducted from the primary winding to the secondary winding can be significantly reduced. The primary winding is wound around one yoke part of the iron core, and each winding part of the secondary winding is wound around both legs, so when in use, only the other yoke part of the iron core is used. The iron core is only magnetized, so the entire core is not magnetized, and therefore no "beat" occurs in the core.

[Example] Hereinafter, an example of the present invention will be described based on the drawings. Reference numeral 10 denotes an iron core formed by layering L-shaped or rectangular silicon steel plates with low effective magnetic permeability at high frequencies, and both leg portions 11a and 11b. and yoke portions 12a, 12b connecting both ends thereof. A primary winding 21 is wound around one of the yoke parts 12a, and two winding parts 22a, which are formed to have the same inductance, are mounted on both leg parts 11a and 11b.
The winding portion 22a of the secondary winding 22 consisting of 22b,
22b are each wound. Secondary winding 22
is constructed by connecting the winding portions 22a and 22b in parallel or in series. The winding part 22
When winding the wires a and 22b around the leg parts 11a and 11b, for example, one winding part 22a is wound with a left-hand winding, and the other winding part 22b is wound with a right-hand winding. Make sure that the polarities match when you connect them. Although not shown, the entire circumference of each of the primary winding 21 and the secondary winding 22a, 22b is coated with a good conductor to prevent noise from being transmitted due to electromagnetic radiation. Reference numeral 23 denotes a conductive shielding plate made of a non-magnetic material such as aluminum placed in the gap between the primary winding 21 and each winding portion 22a, 22b of the secondary winding. E-shaped plate piece 23a inserted in the direction, and this plate piece 23
The shape plate piece 23b is overlapped with the end portion of the shape plate 23b. Both the E-shaped plate piece 23a and the shaped plate piece 23b are arranged so that there is no gap between them and the circumferential surface of the iron core 10.
b has one end overlapped with the E-shaped plate piece 23a through the insulating insertion hole 23c, and the E-shaped plate piece 23a and the shaped plate piece 2
3b to prevent a closed circuit from being formed. Note that the shielding plate 23 is installed inside a transformer box (not shown).

With the above configuration, most of the magnetic flux generated by the low frequency current flowing into the primary winding 21 from the power line passes through the iron core 10 and passes through the secondary winding 21.
As a result, an electromotive force is induced in the secondary winding 22 due to mutual induction. On the other hand, the noise high-frequency current superimposed on the power supply line also flows into the primary winding 21 and generates magnetic flux, but this magnetic flux cannot pass through the iron core 10, which has a low high-frequency effective magnetic coefficient. Therefore, the radiation is radiated into the air in the axial direction of the primary winding 21 and hardly interlinks with the secondary winding 22. Further, electromagnetic waves generated by the high frequency current flowing into the primary winding 21,
That is, the electric lines of force are radiated in a direction perpendicular to the axial direction of the primary winding 21, but
Therefore, it will be consumed as eddy current, and 2
It almost never reaches the secondary winding 22 side, and the shielding plate 23 prevents capacitive coupling between the primary winding 21 and each winding portion 22a, 22b of the secondary winding. , Therefore, the noise conducted from the primary winding 21 to the secondary winding 22 can be significantly reduced. A primary winding 21 is attached to one yoke portion 12a of the iron core, and a primary winding 21 is attached to both leg portions 11a, 11.
Since each of the winding portions 22a and 22b of the secondary winding is wound around b, only the other yoke portion 12b of the iron core is magnetized during use, so that the entire iron core is magnetized. Therefore, no "beat" occurs in the iron core.

In the above, a case has been described in which the primary winding 21 is wound around one yoke part 12a of the iron core, and the secondary winding 22 is wound around both leg parts 11a and 11b. Even if the wires are wound in opposite positions, the same effect will be obtained.

In addition, in the above, one yoke part 12 of the iron core
Although the case where the winding is wound only on the yoke part 12b has been described, it may also be wound on the other yoke part 12b. It goes without saying that the wire is formed in sections and the respective winding sections are individually wound.

[Effects of the invention] As explained above, in the present invention, the primary winding and the secondary winding are wound around the iron core at right angles, and there is a conductive wire between the primary winding and the secondary winding. Since the magnetic shielding plate is provided, it is possible to provide an interference wave shielding transformer which has an excellent noise shielding effect, is relatively small, and has a good transformer function.

Moreover, according to the present invention, either the primary or secondary winding is wound around at least one of the yoke parts of the iron core, and two windings are wound around both legs.
Since each winding part of the other winding consisting of two identical winding parts was wound respectively, one yoke part and one leg part were wound.
Compared to the case where the primary winding and secondary winding are arranged, the part of the iron core that is magnetized is smaller, so the iron core can be used without "beating", and the primary winding and secondary winding This means that it is possible to provide a practical interference wave blocking transformer in which the two are arranged at right angles.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line of FIG. 1, and FIGS. 3 and 4 are schematic front views showing a conventional example. 10...Iron core, 11a, 11b...Legs of the iron core, 12a, 12b...Yoke of the iron core, 21...
Primary winding, 22... Secondary winding, 22a, 22b...
...Winding part of secondary winding, 23... Conductive shielding plate.

Claims (1)

[Scope of utility model registration request] A primary or secondary winding 21, 22, and the leg portions 11a and 11b are each wound with the other two winding portions of the same winding portion; An interference wave blocking transformer in which a conductive shielding plate 23 is arranged between each winding portion of the winding and the other winding.