JP2002217042A - Inductance component and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inductance component and a manufacturing method thereof which adjusts the gap size variation due to a less cutting accuracy of the magnetic core gap so as to make an unwanted air gap null or constant after assembling of the magnetic core, thereby more improving the bias effect and eliminating the need of adhesion of the magnetic core to a permanent magnet. SOLUTION: The inductance component comprises a magnetic core 5 having a plurality of magnetic legs 1a, 1c, 3a, 3c and a magnetic gap and a permanent magnet 2 disposed in the magnetic gap. The permanent magnet 2 is formed by applying a viscous material containing a magnet powder mixed with a liquid resin to the magnetic gap so as to be flush with the end face of one of the magnetic legs or through a predetermined microgap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic element having a coil wound around a magnetic core, and more particularly, to a magnetic element used in various electronic devices and switching power supplies, to which a DC bias is applied, such as a transformer or an inductor. It concerns parts.

[0002]

2. Description of the Related Art Conventionally, a method of arranging a permanent magnet for applying a bias is to insert a plate-shaped permanent magnet formed in advance to a predetermined thickness into a gap of a magnetic core cut in advance and use an adhesive or the like. The magnetic core is bonded and fixed.

FIGS. 10 and 11 are perspective views showing examples of conventional inductance components. FIG. 12 is a plan view showing a magnetic core used for the inductance component of FIGS. 10 and 11, FIG. 13 is a diagram showing a core part used for the magnetic core of FIG. 12, and FIG. 14 is a permanent diagram used for the magnetic core of FIG. FIG. 15 is a view showing a magnet, and FIG. 15 is a view which is used for explaining the assembly of the magnetic core of FIG.

Referring to FIG. 10, an inductance component 50 is of a type called a vertical type, and has a bobbin 56 made of an insulating material and a coil portion made of a conductive wire wound around a winding portion of the bobbin 56 in a horizontal direction. 57 and a magnetic core 55 mounted on the bobbin 56. The terminal block at the lower end of the bobbin 56 is provided with a plurality of pin terminals 59 protruding downward from the bobbin 56 for mounting on a board (not shown).

Referring to FIG. 11, an inductance component 60 is of a so-called horizontal type, which is a coil composed of a bobbin 66 made of an insulating material and a conductive wire wound vertically around a winding portion of the bobbin 66. And a magnetic core 55 mounted on the bobbin 66. The terminal block at the lower end of the bobbin 66 is provided with a plurality of pin terminals 69 protruding downward from the bobbin 6 for mounting on a board (not shown).

As shown in FIG. 12, a conventional magnetic core 55
Are provided in a pair of core portions 1 and 3 formed by abutting end faces of magnetic legs and a magnetic core gap formed by a magnetic leg in the center of each of the core portions 1 and 3, and a permanent magnet for biasing an inductance component. 52. The core 1 includes a base 1b, outer magnetic legs 1a, 1a, and a center magnetic leg 1c. Further, the core portion 3 includes a base portion 3b, an outer magnetic leg 3a and a center magnetic leg 3c each having an end surface on the same plane as each other.

To assemble the magnetic core 55, FIG.
As shown in FIG. 3, the center magnetic leg 1 is shorter than the outer magnetic leg 1a.
c, that is, a permanent magnet having a constant thickness as shown in FIG. 14 is attached to the end face of the central magnetic leg 1c of the E-shaped core portion 1 having the central magnetic leg 1c shorter by the size of the magnetic core gap G1. As shown in FIG. 15, the core portions are attached to the bobbins 56 and 66 shown in FIG. 10 or FIG. 11 so as to be flush with the end surfaces of both outer leg portions as shown in FIG. 1 and
The core portion 3 having no air gap is mounted by abutting the end faces of the magnetic legs.

[0008]

FIG. 16 is a view showing a core portion having an air gap different from that shown in FIG. 12 due to the influence of the cutting accuracy of the magnetic core shown in FIG. 13, and FIG. 17 is used to explain the magnetic core. FIG. 17 is a plan view for explaining the magnetic core.

As shown in FIG. 16, when a permanent magnet 52 similar to that shown in FIG. 14 is attached to a core portion 1 'having an air gap G2 different from the air gap G1 due to the cutting accuracy, FIG. When the core portion 3 having no air gap is brought into contact with the state shown in FIG.
Since the thickness of the plate-shaped permanent magnet 52 does not change, a gap GB is generated in the central magnetic leg of the magnetic core 55 due to the difference between the gaps G1 and G2.

As described above, in the conventional magnetic core, the gap size variation occurs due to the influence of the cutting accuracy of the gap portion of the magnetic core, so that the gap is generated as an air gap even after the permanent magnet is provided.

Further, in a bias inductance component manufactured by a conventional method, a bonding step of a magnetic core with a gap and a permanent magnet and an adhesive are indispensable.

[0012] Further, due to the gap size variation of the magnetic core, an unnecessary air gap after the permanent magnet is provided is generated.
There is a disadvantage that the bias effect is reduced.

Accordingly, a first technical problem of the present invention is to adjust the variation in gab size due to the cutting accuracy of the magnetic core gap, to make the amount of unnecessary air gab after the magnetic core combination zero or constant, and to reduce the bias effect. An object of the present invention is to provide a further improved inductance component.

A second technical object of the present invention is to provide an inductance component which does not require bonding of a magnetic core and a permanent magnet, and a method of manufacturing the same.

A third technical object of the present invention is to provide an inductance component capable of eliminating stress on a magnetic core due to expansion of a permanent magnet, and a method of manufacturing the same.

Further, a fourth technical object of the present invention is to provide an inductance component having excellent DC superposition characteristics even after reflow soldering.

[0017]

In the inductance component according to the present invention, the biasing permanent magnet uses a viscous material in which magnet powder and an adhesive (resin) are mixed, and the viscous material magnet is provided in the magnetic core gap. It is manufactured by applying and curing by heating, for example.

That is, according to the present invention, in an inductance component in which a permanent magnet is disposed in a magnetic gap of a magnetic core having a plurality of magnetic legs and a magnetic gap, the permanent magnet is composed of a magnet powder and a magnetic powder. A viscous material mixed with a liquid resin (for example, an adhesive) is provided in the magnetic gap portion on the same plane as one end face of one of the plurality of magnetic legs, or on the same surface via a predetermined minute gap. Thus, an inductance component characterized by being formed by coating such that

According to the present invention, in the inductance component, the magnet powder of the permanent magnet has a specific coercive force of 7%.
90kA / m (10kOe) or more, Curie temperature Tc5
An inductance component characterized by a rare earth magnet powder having a temperature of at least 00 ° C. and an average particle size of 2.5 to 50 μm is obtained.

Further, according to the present invention, in any one of the inductance components, the magnet powder may include Sm (Co
bal, Fe0.15-0.25, Cu0.05-0.
06, an inductance component, characterized in that it comprises a composition of _{Zr0.02-0.03) 7.0-8.5} is obtained.

Further, according to the present invention, in any one of the inductance components, the surface of the magnet powder may have a volume ratio of 0.1 to 10% Zn, Al, Ga, In,
The magnet powder is coated with one or an alloy of Mg, Pb, Sb, and Sn or a composite is formed, and the magnet powder is subjected to a surface treatment with a dispersing material before being mixed with the resin. Is obtained. Here, in the present invention, as the dispersant, a titanium coupling agent and a silane coupling agent are preferable.

According to the present invention, in any one of the inductance components, the magnetic core includes a plurality of cores, and one of the cores includes a central magnetic leg and a
And a pair of outer magnetic legs formed on both sides of the E-shaped core, wherein the permanent magnet is formed on an end face of a center magnetic leg of the E-shaped core. Can be

According to the present invention, in a method of manufacturing an inductance component of a magnetic core having a plurality of magnetic legs and a magnetic gap, wherein a permanent magnet is disposed in the magnetic gap.
As the permanent magnet, a viscous material obtained by mixing a magnet powder and a liquid resin (for example, an adhesive) is provided in the magnetic gap portion on the same surface as one end surface of one of the plurality of magnetic legs, or is predetermined. A method for manufacturing an inductance component is characterized in that it is applied and formed so as to be on the same surface via a minute gap.

According to the present invention, in the method of manufacturing an inductance component, the permanent magnet has a specific coercive force of 790 kA / m (10 kOe) or more, a Curie temperature Tc of 500 ° C. or more, and an average particle size of 2.5. ~ 50μ
Thus, a method for producing an inductance component, characterized by using m rare earth magnet powders, is obtained.

According to the invention, in any one of the above-described methods for manufacturing an inductance component, the magnet powder may be made of Sm (Cobal, Fe0.15-0.25, Cu
0.05-0.06, Zr0.02-0.03)
_A method for manufacturing an inductance component, which has a composition of _{7.0 to 8.5} , is obtained.

According to the invention, in any one of the above-described methods for manufacturing an inductance component, the surface of the magnet powder may be made to have a volume ratio of 0.1 to 10% of Zn, Al, Ga,
Coating with at least one or at least two kinds of alloys of In, Mg, Pb, Sb, and Sn or forming a composite, and performing a surface treatment with a dispersing material before mixing with the resin. Is obtained. Here, in the present invention, as the dispersant, a titanium coupling agent and a silane coupling agent are preferable.

Further, according to the present invention, in any one of the above-described methods for manufacturing an inductance component, the magnetic core includes a plurality of core portions, and one of the core portions is formed on a central magnetic leg and on both sides thereof. A permanent magnet is formed on the end face of the center magnetic leg of the E-shaped core, and a method of manufacturing an inductance component is obtained.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an example of an inductance component according to the first embodiment of the present invention. Referring to FIG. 1, an inductance component 10 is of a type called a vertical type, and includes a bobbin 6 made of an insulating material, and a coil part 7 made of a conductive wire wound around a bobbin 6 in a horizontal direction. , A magnetic core 5 mounted on the bobbin 6. The terminal block at the lower end of the bobbin 6 is provided with a pin terminal 9 projecting downward from the bobbin 6 for mounting on a board (not shown).

FIG. 2 is a view showing another example of the inductance component according to the first embodiment of the present invention.

Referring to FIG. 2, the inductance component 2
Numeral 0 denotes a type called a horizontal type, in which a bobbin 16 made of an insulating material, a coil part 17 made of a conductive wire wound vertically on a winding part of the bobbin 16, and a magnetic member mounted on the bobbin 16 are provided. And a core 5. The terminal block at the lower end of the bobbin 16 has a structure shown in FIG.
In the same manner as in the example, a pin terminal 19 protruding downward from the bobbin 16 is provided.

FIG. 3 is a plan view showing the magnetic core 5 according to the first embodiment of the present invention used for the inductance component shown in FIGS. FIGS. 4 and 5 are plan views used to explain that the air gap differs depending on the cutting accuracy of the core portion 1 of the magnetic core of FIG.

As shown in FIG. 3, the magnetic core 5 includes a pair of cores 1, 3 formed by abutting end faces of magnetic legs.
And a permanent magnet 2 for biasing an inductance component provided in a magnetic core gap formed by a magnetic leg at the center of each of the core portions 1 and 3.

The core 1 includes a base 1b, outer magnetic legs 1a, 1a extending in parallel in the same direction from the same side surface at both ends of the base 1b, and outer magnetic legs 1a, 1a from the center of the base 1b.
a, and a central magnetic leg 1c extending in the same direction as the center magnetic leg 1c.

On the other hand, the core part 3 includes a base 3b and a base 3b.
Outer magnetic legs 3a, 3a extending in the same direction and parallel to each other from the same side surface at both ends of the base 3b, and the outer magnetic legs 3
a, 1a, and a central magnetic leg 3c extending so that the end face is flush with the end face of the external magnetic leg.

The cores 1 and 3 have a magnetic permeability of 4 × 10 ⁻³ H /
m, a magnetic path length of 0.02 m, and an effective sectional area of 5 × 10 ⁻⁶ m ² . Note that M
In addition to the n-Zn ferrite, a metal soft magnetic material such as silicon steel, amorphous, and permalloy, or a Ni-Zn ferrite soft magnetic material can also be used.

On the other hand, the magnet powder of the permanent magnet 2 is a powder of SmCo alloy powder coated with 3% Zn, a viscous material mixed with an epoxy resin as an adhesive, and has a coercive force of 100 A / m 2 at the time of curing. Above, the residual magnetic flux density 0.4T
It has the characteristic.

As the metal to be coated, in addition to Zn, one or two or more of Al, Ga, In, Mg, Pb, Sb, and Sn can be used as a coating or a composite.

As the magnet, in addition to the SmCo used in the first embodiment, an oxide hard magnetic material such as Ba ferrite or Sr ferrite, or a rare earth sintered powder such as NdFeB may be used. Is possible.

In addition, any of thermosetting or thermo-flexible resins such as polyimide, polyamide imide, and nylon may be used as the adhesive.

In order to assemble the magnetic core 5, as shown in FIG. 4, an E-type having a central magnetic leg 1c shorter than the external magnetic leg 1a, that is, a central magnetic leg shorter by the size of the magnetic core gap G1. As shown in FIG. 6, a viscous body Mg obtained by mixing a magnet powder and an adhesive made of a resin is applied as a permanent magnet 2 to the end face of the central magnetic leg 1c of the core portion 1 as shown in FIG. 1 and 2, the bobbin 6, 16 shown in FIG. 1 and FIG.
Then, the magnetic leg end faces of the core portion 3 having no air gap are abutted and mounted.

As shown in FIG. 5, the core part 1 'of the inductance component according to the first embodiment has a distance G2 between the magnetic core air gap and the core part 1, that is, the center magnetic leg 1c. The distance between the end faces of the outer magnetic leg 1a and the outer magnetic leg 1a differs by a gap GB due to the gap dimension due to the cutting dimension accuracy. (G2-G1 = GB).

However, similarly to the core 1 shown in FIG. 4, the permanent magnet 2 is formed by applying the viscous material Mg to the end face, as shown in FIG. 1 and 2 so as to form a magnetic core similar to that shown in FIGS. 1 and 2, except that the thickness of the permanent magnet of the magnetic core is different from the thickness GB as shown in FIGS. Is formed.

As described above, in the first embodiment of the present invention, by adjusting the application amount of the permanent magnet 2 made of the viscous material Mg, the gap size variation due to the cutting accuracy is eliminated, and the core gap 0 is reduced. An ideal bias inductance component can be obtained, and a bias effect corresponding to the quality of this component can be maximized.

FIG. 7 is a plan view showing a magnetic core of an inductance component according to a second embodiment of the present invention. FIG.
FIG. 8 is a diagram which is used for describing the assembly of the magnetic core of FIG. 7.

Referring to FIG. 7, the magnetic core 15 is provided with the permanent magnet 2 by applying a viscous material Mg between the opposing surfaces of the central magnetic leg, but has a clearance G3. This is different from the magnetic core 5 according to the first embodiment.

To assemble the magnetic core 15, FIG.
And a central magnetic leg 1c shorter than the external magnetic leg 1a, that is, an E-shaped core 1 having a central magnetic leg shorter by the size of the magnetic core gap G1. As shown in FIG. 7, a permanent magnet 2 made of a viscous material Mg is applied and formed on the end face of the magnetic leg 1c so as to correspond to a clearance G3 between the surface of the permanent magnet 2 and the end face of the outer magnetic leg 1a. By providing a dimensional difference as shown in FIG. 1 or FIG. 2, when the magnetic leg end faces of the core portions 1 and 3 are fitted to the bobbin 6 as shown in FIG. G3 is formed.

As described above, by forming the air gap by intentionally providing the clearance G3, this permanent magnet 2
The stress of the magnetic core 15 due to the expansion of the resin can be eliminated, and the quality of the bias inductance component can be improved.

When a core portion 1 'having a different gap dimensional accuracy similar to that shown in FIG. 5 is used, a similar clearance G3 is provided by adjusting the application amount of the viscous material Mg. A magnetic core can be formed, and by forming an air gap between the surface of the permanent magnet 2 and the end face of the central magnetic leg abutted against the permanent magnet, the permanent magnet 2 can be formed.
The stress of the magnetic core 15 due to the expansion of the resin can be eliminated, and the quality of the bias inductance component can be improved.

In the second embodiment, the same materials as in the first embodiment can be used.

FIG. 9 shows the DC superposition characteristics of the inductance component of the present invention, in which the sample according to the first embodiment after reflow soldering is used.
In FIG. 9, the horizontal axis represents current, and the vertical axis represents inductance. In addition, it shows the DC superposition characteristics of the prior art and the reflow soldering for mounting the same on a substrate.

FIG. 9 shows that the product 41 according to the present invention has better characteristics than the conventional product 43 and the conventional product after reflow. This is because, as in the first embodiment, the composition of the material, the specific coercive force, the Curie temperature, and the average particle size are specified, and further, by performing a specific process, irreversible demagnetization due to reflow soldering heat, and This shows that demagnetization due to oxidation can be prevented, and an inductance component having excellent DC superposition characteristics can be provided even after reflow soldering.

[0053]

As described above, according to the present invention,
The magnet powder adheres to the irregularities on the joining surface of the magnetic core and the permanent magnet, and the gap size due to the cutting accuracy of the magnetic core gap is adjusted by the amount of the permanent magnet powder. An inductance component that can be made constant and the bias effect can be further improved can be provided.

Further, in the inductance component of the present invention, it is possible to provide an inductance component in which the permanent magnet is formed by directly applying a viscous material in manufacturing, so that there is no need to bond the magnetic core to the permanent magnet. it can.

Further, in the inductance component of the present invention, by providing a clearance between the permanent magnet and the magnetic core in advance, it is possible to provide an inductance component capable of eliminating stress on the magnetic core due to expansion of the magnet. .

Further, in the present invention, irreversible demagnetization due to heat of reflow soldering and demagnetization due to oxidation can be prevented, and an inductance component having excellent DC superposition characteristics even after reflow soldering can be provided. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an inductance component according to a first embodiment of the present invention.

FIG. 2 is a diagram showing another example of the inductance component according to the first embodiment of the present invention.

FIG. 3 is a plan view showing a magnetic core 5 according to the first embodiment of the present invention used for the inductance component shown in FIGS. 1 and 2;

FIG. 4 is a plan view used to explain that the air gap differs depending on the cutting accuracy of the core portion 1 of the magnetic core of FIG. 3;

FIG. 5 is a plan view used to explain that the air gap differs depending on the cutting accuracy of the core portion 1 of the magnetic core of FIG. 3;

FIG. 6 is a plan view showing a state where a permanent magnet is mounted on the core unit 1 of FIG. 4;

FIG. 7 is a plan view showing a magnetic core of an inductance component according to a second embodiment of the present invention.

8 is a diagram which is used for describing the assembly of the magnetic core of FIG. 7;

FIG. 9 shows a DC superposition characteristic of the inductance component of the present invention, in which a sample according to the first embodiment after reflow soldering is used as one sample.

FIG. 10 is a perspective view showing an example of a conventional inductance component.

FIG. 11 is a perspective view showing another example of the inductance component according to the related art.

FIG. 12 is a plan view showing a magnetic core used for the inductance component of FIGS. 10 and 11;

FIG. 13 is a diagram showing a core portion used for the magnetic core of FIG.

FIG. 14 is a diagram showing a permanent magnet used in the magnetic core of FIG.

15 is a diagram that is used for describing the assembly of the magnetic core in FIG. 12.

16 is a diagram showing a core portion having an air gap different from that of FIG. 12 due to the influence of the cutting accuracy of the magnetic core shown in FIG. 13;

FIG. 17 is a diagram which is used for describing assembly of a magnetic core using the core portion 1 ′ of FIG.

FIG. 18 is a plan view used for describing a magnetic core using the core section 1 ′ of FIG. 16;

[Explanation of symbols]

 1,3 core part 1b, 3b base part 1a, 3a outer magnetic leg 1c, 3c central magnetic leg 2 permanent magnet 5,15 magnetic core 6,16 bobbin 7,17 coil part 9,19 pin terminal 10,20 inductance component 50, 60 Inductance component 56, 66 Bobbin 55 Magnetic core 59, 69 Pin terminal

Claims (10)

[Claims] 1. An inductance component comprising a magnetic core having a plurality of magnetic legs and a magnetic gap, wherein a permanent magnet is disposed in the magnetic gap, wherein the permanent magnet is a mixture of magnet powder and a liquid resin. The viscous material is formed by coating the magnetic gap portion with the same surface as one end surface of one of the plurality of magnetic legs, or the same surface through a predetermined minute gap. Features inductance components. 2. The inductance component according to claim 1, wherein the magnet powder of the permanent magnet has a specific coercive force of 790 kA /
m or more, Curie temperature Tc 500 ° C. or more, average particle size
An inductance component comprising a rare earth magnet powder of 5 to 50 μm. 3. The inductance component according to claim 1, wherein said magnet powder comprises Sm (Cobal, Fe
0.15-0.25, Cu0.05-0.06, Zr
0.02-0.03) An inductance component having a composition of 7.0-8.5. 4. The inductance component according to claim 1, wherein the surface of the magnet powder has a volume ratio of 0.1 to 10% of Zn, Al, Ga, In,
The magnet powder is coated with one or an alloy of Mg, Pb, Sb, and Sn or a composite is formed, and the magnet powder is subjected to a surface treatment with a dispersing material before being mixed with the resin. And the inductance component. 5. The inductance component according to claim 1, wherein the magnetic core includes a plurality of core portions, and one of the core portions includes a center magnetic leg and both sides thereof. An inductance component comprising an E-shaped core having a pair of outer magnetic legs formed thereon, wherein the permanent magnet is formed on an end face of a center magnetic leg of the E-shaped core. 6. A method of manufacturing an inductance component of a magnetic core having a plurality of magnetic legs and a magnetic gap, wherein a permanent magnet is disposed in the magnetic gap.
The viscous material obtained by mixing the magnet powder and the liquid resin is made to be flush with the end face of one of the plurality of magnetic legs in the magnetic gap portion, or so as to be flush with a predetermined minute gap. A method for manufacturing an inductance component, which is formed by coating. 7. The method of manufacturing an inductance component according to claim 6, wherein the magnet powder of the permanent magnet has a specific coercive force of 790 kA / m or more, a Curie temperature Tc of 500 ° C. or more, and an average particle size of 2.5 to 50 μm. A method for manufacturing an inductance component, comprising using powder. 8. The method for manufacturing an inductance component according to claim 6, wherein the magnet powder is Sm (Coba).
1, Fe0.15-0.25, Cu0.05-0.0
6, a manufacturing method of the inductance component, characterized in that it comprises a composition of _{Zr0.02-0.03) 7.0-8.5.} 9. The method of manufacturing an inductance component according to claim 6, wherein the surface of the magnet powder is 0.1 to 10 in volume ratio as the magnet powder.
% Zn, Al, Ga, In, Mg, Pb, Sb, Sn, coated with one kind of metal or an alloy composed of at least two kinds, or formed into a complex and dispersed before mixing with the resin. What is claimed is: 1. A method for manufacturing an inductance component, comprising using a surface-treated material. 10. The method of manufacturing an inductance component according to claim 6, wherein the magnetic core includes a plurality of cores, and one of the cores includes:
An inductance component comprising an E-shaped core having a central magnetic leg and a pair of outer magnetic legs formed on both sides thereof, wherein the permanent magnet is formed on a central magnetic leg end surface of the E-shaped core. Manufacturing method.