JP3247702B2 - Composite magnetic core and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic core having a characteristic that the magnetic permeability becomes non-linear with respect to a DC superimposed magnetic field and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a normal smoothing choke, the permeability of a magnetic core material is nearly constant from a low magnetic field to a magnetic field at which the magnetic core is saturated, and a change in inductance is small even when a current flowing through a coil becomes small.

For this reason, when used as a smoothing choke for a switching power supply, there has been a problem that the output voltage fluctuates when the load current is small. For this reason, the problem has been solved by adding a circuit for suppressing the fluctuation of the output voltage.

[0004]

However, in the above-mentioned technology, problems such as an increase in cost due to an increase in the number of components and an increase in the size of a power supply due to an increase in the number of components occur. Therefore, when the current flowing through the coil is small, the inductance is large. A choke using a core having an L-shaped non-linear characteristic with a small change in magnetic permeability from a certain current or higher until the magnetic core is saturated is required.

In order to solve this problem, a magnetic material having a high magnetic permeability is arranged in the vicinity of the gap of the core, or a half-gap type choke in which a magnetic circuit section of the magnetic material having a high magnetic permeability is partially cut. Proposals for magnetic cores have been made.

However, in these methods, since a gap exists in the magnetic core, there is leakage of magnetic flux from the gap, and
When used in an electronic device or the like, a problem such as noise may occur, which is not preferable.

Further, when there is a load fluctuation at an audio frequency,
When the magnetic core expands and contracts due to the magnetostriction of the magnetic material, and when there is a gap in the magnetic path, the sound is particularly pronounced at the gap, so that it cannot be used in applications where magnetic core noise is a problem.

In order to solve the above-mentioned problem, in the case of Fe-based amorphous alloys, a non-gap type choke having non-linear characteristics is obtained by combining cores that have been heat-treated at different temperatures into one magnetic core. Although it is possible to obtain, it is necessary to perform two heat treatment steps and to further add a step of combining two cores into one magnetic core. There were difficulties.

The present invention has been made in view of the above problems, and an object of the present invention is to efficiently and inexpensively supply a magnetic core having a non-linear magnetic permeability characteristic with respect to a DC superimposed magnetic field. It is in.

[0010]

A first gist of the present invention is as follows.
A composite core obtained by combining and winding an Fe-based amorphous magnetic alloy ribbon and a Co-based amorphous magnetic alloy ribbon to obtain a magnetic core body, and then heat-treating the magnetic core body.
The main body is Fe-based amorphous magnetic alloy ribbon and Co-based amorphous
A composite layer in which magnetic alloy ribbons are alternately wound,
A single layer wound with an amorphous magnetic alloy ribbon or a Co-based
At least one of the single layers wound with amorphous magnetic alloy ribbon
Is a composite magnetic core having one single layer .

The second gist is that the first ribbon is made of Fe-based amorphous
Magnetic alloy ribbon and the second ribbon is Co-based amorphous magnetic
Co-based amorphous as the alloy ribbon or the first ribbon
The second ribbon is a magnetic alloy ribbon, and the second ribbon is an Fe-based amorphous magnetic composite.
The winding of the first ribbon was completed as a gold ribbon
After that, the second ribbon is continuously wound from above and the magnetic core
After obtaining the main body, this core is heat treated.
This is a method for manufacturing a composite magnetic core.

A third gist is that when manufacturing a composite magnetic core,
The first ribbon is an Fe-based amorphous magnetic alloy ribbon, and the second ribbon is
The ribbon may be a Co-based amorphous magnetic alloy ribbon or
The first ribbon is a Co-based amorphous magnetic alloy ribbon and the second ribbon is
Bonn as Fe-based amorphous magnetic alloy ribbon, after completion of the winding of the first ribbon, after obtaining the magnetic core main body subsequently subjected to wind the second ribbon thereon, heat-treated magnetic core body Is what you do.

The fourth gist is that the first ribbon is made of an Fe-based amorphous material.
Magnetic alloy ribbon and the second ribbon is Co-based amorphous magnetic
Co-based amorphous as the alloy ribbon or the first ribbon
The second ribbon is a magnetic alloy ribbon, and the second ribbon is an Fe-based amorphous magnetic composite.
As a gold ribbon , a core body having a double-wound portion (composite layer) in which the second ribbon is inserted while the first ribbon is being wound, and the first and second ribbons are alternately overlapped and wound. After being obtained, the magnetic core body is subjected to a heat treatment.

A fifth gist is that, in the first, second, third or fourth gist, the heat treatment temperature range is from Tx-20 ° C. to Tx with the crystallization temperature of the Fe-based amorphous alloy as Tx.
-100 ° C.

[0015]

The Fe-based amorphous magnetic alloy ribbon and the Co-based amorphous magnetic alloy ribbon constituting the composite magnetic core may be formed into a slit shape, and these may be combined with each other and wound. The ends of these wound bodies can be fixed by attaching a Kapton tape or the like.

The Fe-based amorphous alloy (Fe
Amorphous magnetic alloys) are Fe-based amorphous alloys (metals) in which the content of Fe in the alloy is 50 atomic% or more.
B, Fe-BC, Fe-B-Si, Fe-B-Si-
Fe-based materials such as C, Fe-B-Si-Cr and Fe-Ni-Mo-B can be exemplified.

[0017] Particularly preferred Fe-based amorphous alloy in this can be illustrated _{,, Fe x Si y B z M} w. Where x =
50-85, y = 0-15, z = 5-25 (x, y, z
All represent atomic%). M is N
i, Nb, Ta, Mo, W, Zr, Cu, Cr, Mn,
Metals composed of one or a combination of two or more of C, Al, P, etc., with w = 0 to 5 at% can be exemplified.

As the Co-based amorphous alloy, Co _a
It can be exemplified _{-Fe b -M c -Si d -B e} . Where a =
60-90, b = 0-10, d = 0-15, e = 5-2
5 (each represents atomic%), and M is Ni,
Nb, Ta, Mo, W, Zr, Cu, Cr, Mn, C,
A metal composed of one or a combination of two or more such as Al and P, and c = 0 to 10 (atomic%) can be exemplified.

In the heat treatment, a wet atmosphere may be used as a treatment condition. In this case, the unit amount of water vapor the magnetic core main body at 25 ° C. Conversion is 3~600g / m ^3, particularly preferably it is desirable to heat treatment in a humid atmosphere of 20 to 200 g / m ^3.

The heat treatment temperature is from Tx-20 ° C. to Tx-10
It is preferable to carry out in the range of 0 ° C. (where Tx is the crystallization temperature of the Fe-based amorphous alloy).

Here, the crystallization temperature (Tx) is defined as DSC
This is the peak temperature of the exothermic peak of the first crystallization obtained when measured at a temperature rising rate of 10 ° C./min with a (differential scanning calorimeter).

The atmosphere of the heat treatment may be the same as that of the atmosphere. Preferably, an inert atmosphere such as a nitrogen atmosphere is used to separate the Kapton tape used for stopping the end of the amorphous ribbon. Can also be prevented.

Further, according to the present invention, by inserting magnetic ribbons having different crystallization temperatures during winding of the first ribbon, the end of the first ribbon can be joined with a joining means such as Kapton tape or welding. There is no need to use it, and the magnetic core can be manufactured by a simple winding device.

[0024]

EXAMPLES Examples of the present invention will be described below based on experimental examples and comparative examples.

FIG. 1 is a schematic view showing a magnetic ribbon winding device for obtaining a magnetic core in one embodiment of the present invention.

In FIG. 1, a first roll 3a for supplying a first ribbon 1a and a second roll 3b for supplying a second ribbon 1b are arranged, and a ribbon thickness measuring device 11, a tension detecting roll 4, and a Cutters 5a, 5
b and the ribbon is supplied to the winding core 6 via the ribbon feeding device 9.

In the figure, a tension detector 4, a ribbon thickness measuring device 11, and a ribbon feeding device 9 are shown.
Are arranged in only one ribbon supply system for simplicity of the drawing, but are commonly provided in both supply systems.

An experimental example and a comparative example of obtaining a composite magnetic core using the above-described winding device shown in FIG. 1 will be described below. (Experimental Example 1) First ribbon (1a) Composition: (atomic%): Co _67.7 Fe _3.8 Ni _1.5 Si _13.7 B
_13.4 Thickness: 20 μm Width: 10 mm ・ Second ribbon (1b) Composition: (atomic%): First peak temperature of crystallization of Fe ₈₀ Si ₈ B ₁₂ : 510.5 ° C. Thickness: 21 μm Width: 10 mm First, second roll The second ribbon 1b is fed out from 3b, and a tape piece 10 of Kapton tape is adhered to the tip of the second ribbon 1b so that the adhesive surface is located outside the core 6.

Then, the second ribbon 1b is wound around the winding core 6.
To rotate the winding core 6 by slightly more than one rotation in the direction of the arrow. As a result, the second ribbon 1b is fixed in an annular shape.
As a result, a first single layer composed of the second ribbon 1b is formed .

Next, during the winding of the second ribbon 1b, the starting end of the first ribbon 1a from the first roll 3a is inserted.
The second layer 1b and the first ribbon 1a are alternately wound by the rotation of the core, and the composite layer (1b +
After forming 1a), the first ribbon 1a is cut into a predetermined length by a cutter 5b, and only the second ribbon 1b is wound to form a second single layer, as shown in FIG. The magnetic core body 12 was obtained.

At this time, the first ribbon 1a and the second ribbon 1
The weight ratio to b was 1: 2 (first ribbon 1a: second ribbon 1b).

The outer diameter of the magnetic core body 12 was 25 mm and the inner diameter was 15 mm. The magnetic core body 12 was heat-treated at 450 ° C. for 2 hours in an N ₂ atmosphere in an electric furnace to obtain a composite magnetic core.

FIG. 5 shows the relationship between the magnetic permeability of the composite core thus obtained and the DC superimposed magnetic field. (Experimental Example 2) First ribbon (1a) Composition: (atomic%): Fe ₈₀ Si ₈ B ₁₂ crystallization First peak temperature: 510.5 ° C. Thickness: 21 μm Width: 10 mm Second ribbon (1b) Composition: (atomic%): Co ₆₇ . ₇ Fe ₃ . ₈ Ni ₁ . ₅ S
i ₁₃ . ₇ B ₁₃ . ₄ Thickness: 20 μm Width: 10 mm First, use the winding device shown in FIG.
Is wound a predetermined number of times to form a first single layer, and then the starting end of the first ribbon 1a is inserted into the winding end of the second ribbon 1b, and the first ribbon 1a The second ribbon 1b is wound a predetermined number of times in a state where two sheets are stacked
Then, a composite layer composed of a double winding is formed .

Next, the second ribbon 1b is cut by the cutter 5b.
Is cut, and thereafter, only the first ribbon 1a is wound,
By forming a second single layer, the magnetic core body 13 shown in FIG. 4 was obtained. At this time, the winding amount of both ribbons is the first ribbon 1
a and the second ribbon 1b have a weight ratio of 3: 2 (the first ribbon 1b).
a: Control to be the second ribbon 1b).

The magnetic core body 13 thus obtained had an outer diameter of 25 mm and an inner diameter of 15 mm. The magnetic core body 13 is placed in an electric furnace in an N ₂ atmosphere at 452.
A heat treatment was performed at 2 ° C. for 2 hours to obtain a composite magnetic core.

FIG. 5 shows the relationship between the magnetic permeability of the composite core thus obtained and the DC superimposed magnetic field. (Comparative Example) Ribbon composition: (atomic%): first peak temperature of crystallization of Fe ₈₀ Si ₈ B ₁₂ : 510.5 ° C. thickness: 21 μm width: 10 mm Outer diameter using the winding device shown in FIG. A magnetic core body having a diameter of 25 mm and an inner diameter of 15 mm was obtained. The magnetic core body was heat-treated at 450 ° C. for 2 hours in an N ₂ atmosphere in an electric furnace to obtain a composite magnetic core.

FIG. 5 shows the relationship between the magnetic permeability of the composite core thus obtained and the DC superimposed magnetic field.

From the comparison between the experimental examples 1 and 2 and the comparative example, in this embodiment, when the current flowing through the coil is small, the inductance is large, and the change in the magnetic permeability from a certain current or higher until the magnetic core is saturated. It has become clear that a magnetic core having a small L-shaped characteristic can be obtained.

[0039]

According to the present invention, a non-gap type choke coil having an L-shaped non-linear characteristic can be obtained efficiently and at low cost by a simple manufacturing process. Ma
By using two different (separate) ribbons,
The number of windings and the winding form of the ribbon can be adjusted arbitrarily.
Easy to manufacture magnetic core with characteristics corresponding to required permeability characteristics
Can be obtained. In other words, the magnetic core must be
Even if the required permeability characteristics are the same non-linearity,
Although there are many cases where they are very different, in the present invention, two types of resources are used.
Adjust the number of windings and winding form of the bon to make the weight ratio of each other different
Makes it easy to respond to those requests.
You.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a magnetic coil winding device for obtaining a magnetic core in one embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a winding state of a magnetic ribbon in an embodiment.

FIG. 3 is an explanatory view showing a structure of a magnetic core main body in an example (Experimental example 1).

FIG. 4 is an explanatory view showing a structure of a magnetic core main body in an example (Experimental example 2).

FIG. 5 is a graph showing a change in magnetic permeability with respect to a DC superimposed magnetic field of a magnetic core in Experimental Examples 1 and 2 and Comparative Example in an example of the present invention.

[Explanation of symbols]

 1a 1st ribbon 1b 2nd ribbon 2 Core body 3a 1st roll 3b 2nd roll 4 Tension detection roll 5a, 5b Cutter 6 Core 9 Ribbon Feeding device 10. Tape pieces (Kapton tape) 11. Ribbon thickness measuring device 12, 13 ... Magnetic core body

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroshi Omori 580-32, Takuji Nagaura, Sodegaura-shi, Chiba Mitsui Petrochemical Industries Co., Ltd. (56) References JP-A-1-291408 (JP, A)

Claims (7)

(57) [Claims] The first ribbon is an Fe-based amorphous magnetic alloy ribbon , and the second ribbon is a Co-based amorphous magnetic alloy ribbon.
Or the first ribbon is a Co-based amorphous magnetic alloy
And the second ribbon is an Fe-based amorphous magnetic alloy ribbon.
Te, after completion of the winding of the first ribbon, after obtaining the magnetic core main body subsequently subjected to wind the second ribbon thereon, the manufacture of the composite magnetic core, characterized in that heat treatment of the core body Method. 2. The first ribbon is an Fe-based amorphous magnetic alloy ribbon , and the second ribbon is a Co-based amorphous magnetic alloy ribbon.
Or the first ribbon is a Co-based amorphous magnetic alloy
And the second ribbon is an Fe-based amorphous magnetic alloy ribbon.
Then, the second ribbon is inserted while the first ribbon is being wound, and a magnetic core body having a double wound portion in which the first and second ribbons are alternately wound is obtained. A method for producing a composite magnetic core, comprising subjecting a main body to heat treatment. 3. An apparatus according to claim 1 or 2, the composite its heat treatment temperature range which is a range of Tx-20 ℃ ~Tx-100 ℃ the crystallization temperature of the Fe-based amorphous magnetic alloy as Tx Manufacturing method of magnetic core. 4. A composite magnetic core obtained by combining and winding an Fe-based amorphous magnetic alloy ribbon and a Co-based amorphous magnetic alloy ribbon to obtain a core body, and then heat-treating the core body. The magnetic core body includes a composite layer in which an Fe-based amorphous magnetic alloy ribbon and a Co-based amorphous magnetic alloy ribbon are alternately wound, a single layer in which an Fe-based amorphous magnetic alloy ribbon is wound, or a Co-based non-magnetic alloy ribbon. And at least one of the single layers wound with the crystalline magnetic alloy ribbon. 5. The first ribbon is an Fe-based amorphous magnetic alloy ribbon , and the second ribbon is a Co-based amorphous magnetic alloy ribbon.
Or the first ribbon is a Co-based amorphous magnetic alloy
And the second ribbon is an Fe-based amorphous magnetic alloy ribbon.
And a first ribbon formed by winding the first ribbon in an annular shape.
And a composite layer formed by alternately winding the first ribbon and the second ribbon on the outer peripheral surface of the first single layer, and on the outer peripheral surface of the composite layer. And a second single layer formed by winding the first ribbon.
A composite magnetic core that is heat-treated at a temperature lower than the crystallization temperature of an e-based amorphous magnetic alloy ribbon. 6. The first ribbon is an Fe-based amorphous magnetic alloy ribbon , and the second ribbon is a Co-based amorphous magnetic alloy ribbon.
Or the first ribbon is a Co-based amorphous magnetic alloy
And the second ribbon is an Fe-based amorphous magnetic alloy ribbon.
And a first ribbon formed by winding the first ribbon in an annular shape.
And a composite layer formed by alternately winding the first ribbon and the second ribbon on the outer peripheral surface of the first single layer, and on the outer peripheral surface of the composite layer. A core body having a second single layer formed by winding the second ribbon;
A composite magnetic core that is heat-treated at a temperature lower than the crystallization temperature of an e-based amorphous magnetic alloy ribbon. 7. The heat treatment temperature range according to claim 4, 5 or 6, wherein the crystallization temperature of the Fe-based amorphous magnetic alloy is T.
A composite magnetic core, wherein x ranges from Tx-20 ° C to Tx-100 ° C.