JPH04106911A - Common mode choke coil - Google Patents

Abstract

PURPOSE:To suppress the adverse effect to other electronic parts, etc., and improve noise eliminating properties by positioning a core, which has a proximate crossover part, between the coils, which are wound in the same direction with the equal number of windings on the surface of the core of a closed magnetic path. CONSTITUTION:When currents I to be supplied to load are let flow to coils 5 and 6, magnetic fluxes phi1 and phi2 are induced in the core 2. The magnetic fluxes phi1 and phi2 are the one whose directions are opposite and whose intensities are the same, so they negative each other inside the core 2, and prevent the magnetic saturation of the core 2. Accordingly, to the current I to be supplied to load, this choke coil does not work at all. On the other hand, when common mode noise currents I (N) flow to the coils and 5 and 6 from lead wires A2 and B2, the magnetic fluxes in the same direction and of the intensity are induced, and the magnetic fluxes strengthen each other. Accordingly, to the common mode noise currents I (N), this choke coil works as an inductance. Though some of the magnetic fluxes phi1 and phi2 leak to the outside, the leakage magnetic fluxes phi8 of the coils never spread on all sides, and can be contained in the space between the crossover parts 2c-2d. Besides, the length of the magnetic path of the leakage magnetic flux phi8 shortens, and the intensity of the leakage magnetic flux phi8 is increased.

Description

[Detailed Description of the Invention] Minekajobei M Monthly Gold! The present invention relates to a common mode choke coil that removes common mode noise in an AC circuit.

11. As this type of common mode choke coil, for example, the one shown in FIG. 5 is known. A pair of fills 35, 3 are provided on the legs 31a, 31b of the core 31 of the Japanese-shaped closed magnetic circuit.
6 are wound in a single layer in mutually opposite directions with the same number of turns. The coils 35, 36 are arranged parallel to each other, and from both ends of the coils 35, 36 leads iA5°A6. B
S and B6 are pulled out. An equivalent electric circuit of this choke fill is shown in FIG.

In the choke coil having the above structure, lead wire A5.
When the current supplied to the load from B6 is passed through the filters 35 and 36 (see FIG. 6), magnetic flux is generated within the core 31. However, as shown in FIG. 5, part of this generated magnetic flux leaks from the arm portion 31c at the end of the core 31 to
leaks into the space around the choke coil. The leakage magnetic flux φ38 leaking around the choke coil may have an adverse effect on other electrical components of the electrical equipment in which the choke coil is mounted.

On the other hand, in actual circuits, it has been found that choke coils that allow some degree of magnetic flux leakage are more effective at removing noise.

Therefore, an object of the present invention is to have an excellent noise removal effect by generating a certain amount of leakage flux, and
The object of the present invention is to obtain a common mode choke film that suppresses the adverse effects of the leakage magnetic flux on other electrical components.

Means for Solving the Problems In order to solve the above problems, a common mode choke coil according to the present invention includes a closed magnetic circuit core and a pair of coils arranged substantially parallel to each other, the cores being close to each other. The core is characterized in that the pair of coils are wound on the surface of the core with the same number of turns in the same direction, with the adjacent crossing portions in between. That is, four of the pair of coils are provided on the surface of the core so that the magnetic fluxes generated by the X current supplied to the load are directed in opposite directions.

In the common mode choke coil configured as described above, the cores have a portion where they intersect closely, and a pair of coils is provided between the adjacent intersecting portions, so the leakage magnetic flux of each coil is as follows. It is mostly confined to the adjacent intersections of the core without spreading out in all directions. Furthermore, since the pair of fills are arranged substantially parallel to each other, a relatively large leakage flux can be ensured, and the noise removal effect will not deteriorate compared to conventional choke coils.

Embodiments Hereinafter, embodiments of the common mode choke coil according to the present invention will be described with reference to the accompanying drawings.

[First Embodiment, Figures 1 to 3 Figures 1 and 2 are a front view and a plan view of a chalk fill, respectively. The core 2 of the closed magnetic circuit has leg portions 2a and 2b provided with coils, which will be described later, and a proximal intersection portion 2c.

2d and arm portions 2e, 2f, 2g, and 2h. The legs 2a, 2b are parallel and juxtaposed, and the proximal intersections 2c, 2d are closely opposed. For example, ferrite is used for the core 2.

A pair of coils 5°6 provided on the legs 2a and 2b of the core 2
are wound in a single layer in the same direction with the same number of turns.

The coils 5 and 6 are arranged in parallel to ensure a relatively large leakage flux. Therefore, the choke coil has an excellent noise removal effect. Lead wires A1. A2, B1. B2 is fully drawn out. An equivalent electric circuit of this choke coil 1 is shown in FIG.

When the magnetic flux supplied to the load is passed through the coils 5 and 6 from the node wires Al and B2, a magnetic flux φ1. φ2 occurs (see Figure 1). Magnetic flux di and magnetic flux φ generated in core 2
Since the magnetic fluxes 2 and 2 are opposite in direction and have the same intensity, they cancel each other out within the core 2 to prevent magnetic saturation of the core 2. Therefore, this choke coil has no effect on the current I supplied to the load. On the other hand, lead wire 2. When the humon mode noise current I(N) flows from B2 to the coils 5 and 6, magnetic fluxes of the same intensity and in the same direction are generated within the core 2, and the magnetic fluxes strengthen each other within the core 2. Therefore, this choke fill acts as an inductance with respect to the common mode noise current I(N).

By the way, as shown in FIG. 2, the magnetic flux φ1. A part of φ2 leaks to the outside world, but since the intersection parts 2c and 2d of the core 2 are placed close to each other, the coils 5 and 6
The leakage magnetic flux φ8 leaks from the intersection 2c to the intersection 2d without spreading in all directions. Therefore, most of the leakage magnetic flux can be confined in the space between the intersections 2 cm 2 d. Moreover, the magnetic path length of the leakage magnetic flux φ8 is shortened at the intersections 2c and 2d of the core 2, and the strength of the leakage magnetic flux φ8 is increased compared to the conventional choke coil.

[Second Embodiment, FIG. 4] The common mode choke coil shown in FIG. 4 includes an ω-shaped closed magnetic circuit core 21 and a pair of fills 25 and 26. An intersection 21c where the core 21 is close to each other.

With 21d in between, both ends 21a and 21b of the core 210
are provided with coils zs and zFh. coil 25
．． 26 are wound in a single layer in the same direction with the same number of turns.

The coils 25 and 26 are arranged substantially parallel to each other, ensuring a relatively large leakage flux. When a current to be supplied to the load is passed through the coils 25 and 26, a magnetic flux of -3° φ4 is generated within the core 21. A part of the generated magnetic flux leaks to the outside world, but since the intersecting parts 21c and 21d of the core 21 are placed close to each other, the leakage magnetic flux leaks from the intersecting part 21c to the intersecting part 21d. Therefore, most of the leakage magnetic flux is transferred to the intersection 21cm.
It can be confined in the space between 21d.

[Other Embodiments] The common mode choke coil component according to the present invention is not limited to the embodiments described above, and can be modified in various ways within the scope of the gist.

In particular, the shape of the core, the formation position of the coil, etc. can be arbitrarily modified.

Effects of the Invention As is clear from the above explanation, according to the present invention, the cores having adjacent and intersecting portions are wound in the same direction with the same number of turns on the surface of the core of the closed magnetic circuit. Because it is located between the cores, the leakage magnetic flux generated when the IE current supplied to the load is passed through the coil does not spread in all directions, but leaks from one side of the core's close intersection to the other, narrowing the leakage magnetic flux. It can be confined in space. This provides a common mode choke coil that does not need to be worried about the adverse effects of leakage magnetic flux on other electrical components.

In addition, since the pair of coils are arranged substantially parallel to each other, a relatively large leakage flux is ensured, and the magnetic path length of the leakage flux can be shortened at the close intersection of the cores.
The leakage magnetic flux is stronger than before. Therefore, excellent noise removal characteristics can be obtained.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of a common mode choke coil according to the present invention, FIGS. 1 and 2 are a front view and a plan view of the choke coil, and FIG. 3 is an electrical equivalent thereof. It is a circuit diagram. FIG. 4 is a plan view showing a second embodiment of the common mode choke coil according to the present invention. 5 and 6 show a conventional example. FIG. 5 is a front view of a choke coil, and FIG. 6 is an electrical equivalent circuit diagram thereof. 2... Core, 2c, 2d... Proximity intersection, 5, 6...
...Fino murmur 21...Core, 21c, 21d...
Proximity intersection, 25.26...coil. Patent applicant Murata Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A closed magnetic circuit core and a pair of coils arranged substantially parallel to each other, the cores have a portion where they intersect close to each other, and the pair of coils touch the surface of the core with the close intersection portion in between. A common mode choke coil characterized in that the coils are wound in the same direction with a number of turns equal to .