JP5687374B1 - Common mode choke coil - Google Patents

Abstract

A common mode choke coil having improved inductance, high common mode noise absorption and blocking performance is provided. An area of a cross section perpendicular to a magnetic path in an outer leg portion is set to be 108% or more and 200% or less of an area of a cross section perpendicular to the magnetic path in a core portion. Thereby, AL value can improve and inductance can be raised by making the cross-sectional area of the outer leg part 11 larger than the cross-sectional area of a core part. [Selection] Figure 1

Description

  The present invention relates to a common mode choke coil that absorbs or blocks common mode noise.

  A common mode choke coil is known in which a gear bobbin is mounted on a MnZn ferrite soft magnetic core constituting a square closed magnetic circuit and wound by driving the gear.

  Patent Document 1 is a common mode choke coil in which a soft magnetic core is disposed so as to stand on a mounting surface.

  Patent Document 2 is a common mode choke coil in which a soft magnetic core is arranged in parallel to a mounting surface.

JP-A-10-144546 Japanese Patent Laid-Open No. 10-233327

  The common mode choke coil is required to have a high inductance in order to absorb or prevent common mode noise. However, the inductance of the common mode choke coil is in a trade-off relationship with respect to the market demand for miniaturization of various electronic devices, and it has been difficult to achieve both miniaturization and high inductance.

In order to increase the performance margin related to downsizing and high inductance in common mode choke coils, it is important to improve the _AL value obtained by dividing the inductance by the square of the number of turns of the coil winding. is there.

  An object of the present invention is to provide a common mode choke coil having high inductance, high absorption and blocking performance of common mode noise even when downsized.

  To solve the above-mentioned problems, the present invention provides an integrally formed soft magnetic rhombus-shaped core having a winding core portion, an outer leg portion, and a connecting portion that connects both ends of the winding core portion and the outer leg portion, and a gear bobbin. A winding having a pair with the same number of turns and a terminal block, the gear bobbin is mounted on the winding core, and the winding is wound on the gear bobbin, The area of the cross section perpendicular to the magnetic path can be solved by a common mode choke coil that is 108% or more and 200% or less of the area of the cross section perpendicular to the magnetic path in the core portion.

  In addition, when the width along the direction connecting the center of the core part and the center of the outer leg part is W in the outer leg part, the inner peripheral surface of the connection part of the outer leg part and the connecting part has a curvature. It is desirable that the curved surface has a radius W or more.

  In addition, it is desirable that the rectangular core has a 180-degree rotationally symmetric shape with respect to a straight line connecting the longitudinal center of the core portion and the longitudinal center of the outer leg portion.

  In addition, the lower core is erected from the mounting surface when the winding core portion is farthest from the mounting surface and the outer leg portion is closest to the mounting surface. In the outer leg portion, the width along the mounting surface with respect to the longitudinal direction is wider than the width along the mounting surface with respect to the longitudinal direction in the winding core portion, and the outer periphery of the outer leg portion The surface is preferably fixed on the terminal block.

  The terminal block further includes a core mounting portion and an insulating plate portion, and the outer leg portion is held by being sandwiched between the core mounting portion and the insulating plate portion, and the insulating plate portion is Desirably, the outer leg portion and the winding are disposed.

  Further, if the width along the direction connecting the center of the core part and the center of the outer leg part in the outer leg part is W, the inner peripheral surface and the outer periphery of the connecting part of the outer leg part and the connecting part The surface is configured by a curved surface having a radius of curvature W or more, the surface facing the connection portion in the insulating plate portion is configured by a curved surface having a radius of curvature equal to or less than the radius of curvature of the inner peripheral surface, and the core mounting portion It is desirable that the surface facing the connecting portion is a curved surface having a radius of curvature greater than or equal to the radius of curvature of the outer peripheral surface.

  According to the present invention, the cross-sectional area of the outer leg part is made larger than the cross-sectional area of the core part of the R-shaped core, and the inner peripheral corner part and the outer peripheral corner part are constituted by curved surfaces, so that the size is small and the R-shaped. A common mode choke coil with improved core and winding resource savings and inductance can be obtained.

  In particular, in a vertical common mode choke coil with a square core standing upright, the square core before bonding is hard to fall down and is smoothly inserted into the terminal block, so that the assembly workability can be improved.

It is a perspective view which shows the common mode choke coil of Embodiment 1 in this invention. It is the bottom view which shows the common mode choke coil of Embodiment 1 in this invention, and is the figure seen from the terminal side. It is a perspective view of the terminal block in the common mode choke coil of Embodiment 1 of the present invention. It is a perspective view which shows the common mode choke coil of Embodiment 2 in this invention. In the common mode choke coil of the present invention, the core cross-sectional area ratio, which is the ratio of the area of the cross section perpendicular to the magnetic path in the outer leg portion of the square-shaped core to the area of the cross section perpendicular to the magnetic path in the core portion; It is a figure which shows the relationship of _L value. Shows the inner diameter is the radius of curvature of the inner peripheral surface of the hollow square-shaped core in the common mode choke coil of the present invention, the volume of the A _L value and b-shaped core when changing the outer diameter is the radius of curvature of the outer peripheral surface FIG.

(Embodiment 1)
FIG. 1 is a perspective view showing a common mode choke coil according to the first embodiment of the present invention.

  A rectangular core 1 integrally formed of a soft magnetic material such as MnZn ferrite is hidden in the gear bobbin 2 and is not shown in the figure, a core part, an outer leg part 11, and a connection that connects both ends of the core part and the outer leg part 11. Parts 121 and 122.

  The square-shaped core 1 is placed on the terminal block 4.

  The gear bobbin 2 is mounted on a winding core portion, and windings 31 and 32 having pairs having the same number of windings are wound around each other.

  The terminal block 4 is provided with terminals 401, 402, 403 and another terminal (not shown), and an insulating plate part 41 for ensuring electrical insulation between the windings 31, 32 and the rectangular core 1. Yes.

  Here, the area of the cross section perpendicular to the magnetic path in the outer leg portion 11 is 108% or more and 200% or less of the area of the cross section perpendicular to the magnetic path in the core portion.

Thus, the cross-sectional area of the outer leg 11 is made larger than the cross-sectional area of the winding core, as described below, to improve the A _L value, it is possible to increase the inductance.

On the other hand, since a sufficient _AL value can be secured even if the cross-sectional area of the winding core portion is relatively reduced, resource saving of the windings 31 and 32 is also achieved.

  As an effective range for resource saving of the rectangular core 1 and the windings 31 and 32, an upper limit and a lower limit are provided in the ratio of the cross-sectional area of the core part and the cross-sectional area of the outer leg part 11.

When the width along the direction connecting the center of the winding core portion and the center of the outer leg portion 11 in the outer leg portion 11 is W, the inner peripheral surface and the outer periphery of the connecting portion 13 of the outer leg portion 11 and the connecting portions 121 and 122. The surface is formed of a curved surface having a curvature radius W.

This reduces the magnetic path of the first inner peripheral corner portion B-shaped core, it is possible to further improve the A _L value.

Further, a magnetic flux is hardly pass, by reducing the B-shaped core 1 circumference edge which does not contribute to A _L value increase, leading to resource saving.

  The R-shaped core 1 has a 180-degree rotationally symmetric shape with respect to a straight line connecting the longitudinal center of the winding core portion and the longitudinal center of the outer leg portion 11.

  Thereby, even if the low-shaped core 1 is turned upside down in the assembly process, assembly failure does not occur, and assembly productivity can be improved.

  FIG. 2 is a bottom view showing the common mode choke coil according to the first embodiment of the present invention, as viewed from the terminal side.

  The terminal block 4 includes terminals 401, 402, 403, 404, support portions 421, 422 that support the gear bobbin 2 from the bottom, and restriction portions 431, 432 that restrict the end portions of the windings 31, 32 from being routed.

  The end portion 311 of the winding 31 is conductively connected to the terminal 401 while being routed by the regulating portion 431.

  The end 312 of the winding 31 is conductively connected to the terminal 402 as it is.

  The end portion 321 of the winding 32 is conductively connected to the terminal 403 while the routing is restricted by the restriction portion 432.

  The end 322 of the winding 32 is conductively connected to the terminal 404 as it is.

  Since the end portions 311 and 321 are restricted by the restricting portions 431 and 432, an insulation distance described later can be secured between the inner peripheral surface of the not-shown square core.

  FIG. 3 is a perspective view of a terminal block in the common mode choke coil according to the first embodiment of the present invention.

  In FIG. 3, the routing of the end portion 311 is indicated by a broken line.

  When the end portion 311 is drawn from the inside of the terminal block 4, the restriction portion 431 takes a distance from the mounting portion 44 of the square core, and an insulation distance from the square core is ensured.

(Embodiment 2)
FIG. 4 is a perspective view showing a common mode choke coil according to the second embodiment of the present invention.

  1 differs from FIG. 1 in the first embodiment mainly in that the square-shaped core 1 is erected with respect to the mounting surface.

  That is, in the round core 1, the core portion (not shown) that is covered by the gear bobbin 2 is farthest from the mounting surface on which the terminals 402, 403, and 404 and the terminals (not shown) are mounted, and the outer leg portion 11 is mounted. By being closest to the surface, the square core 1 is arranged so as to stand upright from the mounting surface.

  A width D1 along the mounting surface with respect to the longitudinal direction in the outer leg portion 11 is wider than a width D2 along the mounting surface with respect to the longitudinal direction in the winding core portion, and the outer peripheral surface of the outer leg portion 11 is It is fixed on the mounting portion 44 on the terminal block 4 with an adhesive or the like.

  Thereby, since the outer leg part 11 is wide, even if the square-shaped core 1 is installed vertically, it is difficult to fall on the terminal block 4, and in particular, the square-shaped core is fixed to the terminal block 4 by bonding or the like. Good pre-assembly workability.

  The terminal block 4 includes a mounting portion 44 and an insulating plate portion 41, and is held by the outer leg portion 11 being sandwiched between the mounting portion 44 and the insulating plate portion 41.

  As a result, the outer leg portion 11 is sandwiched between the placing portion 44 and the insulating plate portion 41, whereby the square core 1 can be more stably fixed to the terminal block 4.

  The insulating plate portion 41 is disposed between the outer leg portion 11 and the windings 31 and 32 so as to ensure electrical insulation.

  Further, when the width along the direction connecting the center of the core portion and the center of the outer leg portion 11 in the outer leg portion 11 is W, the inner peripheral surface of the connecting portion 13 of the outer leg portion 11 and the connecting portions 121 and 122. And the outer peripheral surface is configured by a curved surface having a radius of curvature W or more, and the surface facing the connecting portion 13 in the insulating plate portion 41 is configured by a curved surface having a radius of curvature equal to or smaller than the radius of curvature of the inner peripheral surface. The surface facing the portion 13 is a curved surface having a radius of curvature equal to or greater than the radius of curvature of the outer peripheral surface.

  Thus, the terminal block 4 is configured with a curved surface along the rectangular core 1 rather than inserting the rectangular core into the terminal block configured at a right angle as in Patent Document 1. The square core 1 can be smoothly inserted, and the assembly workability is good.

FIG. 5 shows the ratio of the cross-sectional area perpendicular to the magnetic path in the outer leg portion of the square core in the common mode choke coil of the present invention to the cross-sectional area perpendicular to the magnetic path in the core portion. It is a figure which shows the relationship between ratio and _AL value.

The effect of improving the _AL value is recognized when the core cross-sectional area ratio is in the range of 108% to 200%.

When the core cross-sectional area ratio exceeds 200%, the effect of improving the _AL value is saturated.

6, A _L value and b-shaped core when changing the inner diameter is the radius of curvature of the inner peripheral surface of the hollow square-shaped core in the common mode choke coil of the present invention, the outer diameter is the radius of curvature of the outer peripheral surface FIG.

By taking a large inner and outer diameters, while reducing the volume of the hollow square-shaped core, A _L value is increased.

DESCRIPTION OF SYMBOLS 1 B-shaped core 2 Gear bobbin 4 Terminal block 11 Outer leg part 13 Connection part 31, 32 Winding 41 Insulation board part 44 Mounting part 121 Connection part 311, 312, 321, 322 End part 401, 402, 403, 404 Terminal 421 Support part 431, 432 Restriction part W, D1, D2 Width

Claims (6)

An integrally formed soft magnetic rhombus-shaped core having a winding core portion, an outer leg portion, and a connecting portion that connects both ends of the winding core portion and the outer leg portion;
A gear bobbin,
Windings having pairs with the same number of turns,
With a terminal block,
The gear bobbin is attached to the core part,
The winding is wound around the gear bobbin;
The common mode choke coil, wherein an area of a cross section perpendicular to the magnetic path in the outer leg portion is 108% or more and 200% or less of an area of a cross section perpendicular to the magnetic path in the core portion. When the width along the direction connecting the center of the core part and the center of the outer leg part in the outer leg part is W,
2. The common mode choke coil according to claim 1, wherein an inner peripheral surface of a connection portion between the outer leg portion and the connecting portion is formed by a curved surface having a curvature radius W or more.   2. The shape according to claim 1, wherein the square-shaped core has a 180-degree rotationally symmetric shape with respect to a straight line connecting a longitudinal center of the core portion and a longitudinal center of the outer leg portion. Item 3. The common mode choke coil according to Item 2. Of the above-mentioned R-shaped core,
The winding core is furthest away from the mounting surface;
The outer leg is closest to the mounting surface,
The square core is arranged to stand upright from the mounting surface,
The outer leg has a width along the mounting surface with respect to the longitudinal direction.
Wide than the width along the mounting surface with respect to the longitudinal direction in the core portion,
The common mode choke coil according to any one of claims 1 to 3, wherein an outer peripheral surface of the outer leg portion is fixed on the terminal block. The terminal block further includes a core mounting portion and an insulating plate portion,
The outer leg portion is held by being sandwiched between the core mounting portion and the insulating plate portion,
The common mode choke coil according to claim 4, wherein the insulating plate portion is disposed between the outer leg portion and the winding. When the width along the direction connecting the center of the core part and the center of the outer leg part in the outer leg part is W,
The inner peripheral surface and the outer peripheral surface of the connecting portion of the outer leg portion and the connecting portion are configured with curved surfaces having a curvature radius W or more,
The surface of the insulating plate portion that faces the connection portion is configured by a curved surface having a curvature radius equal to or less than the curvature radius of the inner peripheral surface
The common mode choke coil according to claim 5, wherein a surface of the core mounting portion that faces the connection portion is configured by a curved surface having a curvature radius that is equal to or greater than the curvature radius of the outer peripheral surface.

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