JP2002158116A - Inductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inductor that can maintain a high magnetic inductance value even at a large current value, does not demagnetize a permanent magnet since eddy current loss and abnormal current heat generation cannot occur easily, has a relatively small size, and can contribute to the miniaturization and thinning of electronic equipment that is manufactured by using the inductor. SOLUTION: The permanent magnet 23 facing a gap G of a magnetic core 21 includes a base 24, the magnetic core 21, and a coil 22; and is arranged at empty space within the maximum shape of the inductor that is prescribed by the component of the inductor excluding the permanent magnet 23.

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 an inductor and a transformer used in various electronic devices and power supplies for reducing core loss by using a DC bias. About.

[0002]

2. Description of the Related Art In recent years, various electronic devices have been reduced in size and weight. Accordingly, the relative volume ratio of the power supply unit to the entire electronic device tends to increase. This is because it is difficult to miniaturize magnetic components such as inductors and transformers, which are indispensable for the circuit elements of the power supply unit, while various circuits are implemented as LSIs. Various methods have been tried.

In order to reduce the size and weight of magnetic elements such as inductors and transformers (hereinafter collectively referred to as inductors), it is effective to reduce the volume of a magnetic core made of a magnetic material. Generally, when the size of the core is reduced, the magnetic core is likely to be magnetically saturated, so that there is a problem in that the current value that can be handled as a power source is reduced. As a measure for solving this problem, a technique is known in which a magnetic gap (gap) is provided in a part of the magnetic core to increase the magnetic resistance of the magnetic core and prevent the current value from decreasing. However, in this case, the magnetic inductance of these magnetic components decreases.

As a method for preventing the magnetic inductance from decreasing, for example, Japanese Patent Application Laid-Open No. H01-169905 describes a technique relating to the structure of a magnetic core using a permanent magnet for generating a magnetic bias. In this technique, a direct current magnetic bias is applied to a magnetic core using a permanent magnet, and as a result, the number of lines of magnetic force that can pass through a magnetic gap is increased. However, since the magnetic flux generated by the coil wound around the magnetic core passes through the permanent magnet in the magnetic gap, there is a problem that the permanent magnet is demagnetized due to eddy current loss or abnormal current heating. In addition, there is a problem that the smaller the shape of the permanent magnet inserted into the magnetic air gap, the greater the effect of demagnetization due to external factors.

[0005] Therefore, there is a demand for an inductor having a small magnetic core volume, in which the shape of the permanent magnet to be provided is less limited and the permanent magnet is not demagnetized by the magnetic flux generated by the coil wound around the magnetic core. ing. In order to realize such an inductor, for example, Japanese Patent Application Laid-Open No. 08-316
No. 049 discloses a magnetic core in which two core pieces are opposed to each other via a magnetic gap to form a closed magnetic circuit, a coil wound around at least one of the magnetic cores, In an inductor having a permanent magnet for bias provided on a core, the permanent magnet is placed on the outer surface of the magnetic core so that a bias magnetic flux generated by the permanent magnet and a magnetic flux generated by the coil flow in the magnetic core so as to face each other. Among them, an inductor arranged in a bridge manner on a gap is disclosed.

FIGS. 14A to 14D show a conventional technique of this kind. Referring to FIGS. 14A to 14D, a magnetic core 11 is inserted into coil 12 wound around bobbin 14. Then, the permanent magnet 13 is
Are mounted on the gap G in a bridging manner.

The magnetic core 11 in which the permanent magnet 13 is mounted on the gap G in a cross-linked manner maintains a high magnetic inductance value even at a larger current value, as compared with the magnetic core without the permanent magnet 13 mounted. In addition, since the magnetic flux generated by the coil hardly passes through the magnetic path including the permanent magnet 13, eddy current loss and abnormal current heating hardly occur, and therefore, the permanent magnet is not demagnetized.

[0008]

However, the inductor disclosed in Japanese Patent Application Laid-Open No. 08-316049 is
As is clear from FIGS. 14A, 14C and 14D, since the permanent magnet is arranged on the outer surface of the magnetic core, the permanent magnet is disposed in the gap disclosed in Japanese Patent Application Laid-Open No. 01-169905. There is a disadvantage that the size is larger than that of an inductor having a magnet.

Therefore, an object of the present invention is to maintain a high magnetic inductance value even at a large current value, and to prevent eddy current loss and abnormal current heating from occurring, so that the permanent magnet is not demagnetized. It is an object of the present invention to provide an inductor which is relatively small in size and can contribute to miniaturization and thinning of an electronic device manufactured using the present inductor.

[0010]

According to the present invention, a coil is wound around a core side of a magnetic core having a magnetic gap,
Further, in an inductor having a permanent magnet disposed so as to face the magnetic gap, the permanent magnet includes the magnetic core and the coil, but is defined by components of the inductor excluding the permanent magnet. An inductor is obtained, which is arranged in an empty space within the maximum outer shape of the inductor.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an inductor according to an embodiment of the present invention will be described with reference to the drawings.

[First Embodiment] FIGS. 1A to 1C are views for explaining an inductor according to the present embodiment, and FIGS. 2A to 2C show the structure of the present inductor. FIG.

Referring to FIGS. 1A to 1C, the present inductor has a coil wound around a core side of a magnetic core 21 made of a soft magnetic material having a magnetic air gap (gap) G. This is an inductor in which a permanent magnet is disposed so as to face the gap G. However, in this drawing, the permanent magnet is not shown for convenience of explanation. In the present inductor, the magnetic core 21 is composed of two substantially E-shaped core pieces.
Each core side end face is abutted, and furthermore, it is arranged horizontally. Further, the present inductor has a base 24 also serving as a bobbin on which a coil 25 is wound and a terminal 25 to which a winding end of the coil 22 is electrically connected is implanted.

In the figure, a region denoted by reference numeral RS includes a base 24, a magnetic core 21, and a coil 22, while excluding a permanent magnet, an empty space within the maximum outer shape of the inductor defined by the components of the present inductor. (Or invalid space). Even if some component is arranged in the empty space RS, when the present inductor is mounted on an electronic circuit board through a reflow process or the like, a portion protruding from the outer shape of the inductor does not occur. Needless to say, it does not interfere with the communication.

Referring to FIGS. 2A to 2C, the two permanent magnets 23 face the gap G and include the base 24, the magnetic core 21, and the coil 22, while the permanent magnets 23 Reference numeral 23 is provided in an empty space RS (FIG. 1) within the maximum outer shape of the inductor defined by the components of the present inductor except for the reference numeral 23.

The magnetic core 21 is made of Mn-Zn ferrite, has a magnetic permeability of 4 × 10 ⁻³ H / m, and a magnetic path length of 0.1 × 10 ⁻³ H / m.
02 m, and the effective area is 5 × 10 ⁻⁶ m ² .

On the other hand, the permanent magnet 23 is a sintered Ba-based ferrite magnet and has characteristics such that the coercive force is 100 A / m or more and the residual magnetic flux density is 0.4 T.

FIG. 13 shows the inductor shown in FIG.
As a comparative example, a DC superposition characteristic with an inductor having the same configuration as that of FIG. 2 except that the permanent magnet 23 is not provided is shown. As is clear from FIG. 13, the present inductor having the permanent magnet 23 is superior to the inductor having no permanent magnet in the DC superposition characteristics.

More specifically, as the permanent magnet 23,
As a result of the examination, the specific coercive force was 10 KOe or more and Tc was 5
A bonded magnet having a volume ratio of a rare earth magnet powder having a powder average particle diameter of at least 00 ° C. of 2.5 to 50 μm of 30% or more and a specific resistance of 1 Ωcm or more is preferable.

More preferably, the composition of the rare earth alloy is S
_{m (Co bal. Fe 0.15-0 .25} Cu
_0.05-0.06 Zr _0.02-0.03 )
_7.0-8.5 , and the type of resin used for the bonded magnet is any of polyimide resin, epoxy resin, polyphenylsulfite resin, silicone resin, polyester resin, aromatic nylon, and chemical polymer. ,
The rare earth magnet powder contains a silane coupling material and a titanium coupling material.

In order to obtain higher characteristics, the bond magnet is made anisotropic by the magnetic field orientation at the time of fabrication, and the magnetizing magnetic field of the bond magnet is set to 2.5 T or more and magnetized after assembly. It has been discovered that an excellent DC superposition characteristic can be obtained, and that a magnetic core without deterioration of the core loss characteristic can be formed. This is because the magnet characteristics necessary for obtaining excellent DC superposition characteristics are not the energy product but the intrinsic coercive force, and therefore, even if a permanent magnet having a high specific resistance is used, the intrinsic coercive force is high. For example, it has been found that a sufficiently high DC superimposition characteristic can be obtained.

A magnet having a high specific resistance and a high specific coercive force can be generally obtained by a rare earth bonded magnet formed by mixing a rare earth magnet powder with a binder, but if the magnet powder has a high coercive force, Any composition is possible. The type of rare earth magnet powder is SmCo type,
Although there are NdFeB type and SmFeN type, considering the reflow conditions and oxidation resistance, a magnet having a Tc of 500 ° C. or more and a coercive force of 10 KOe or more is required.
Limited to 2Co17-based magnets.

As the magnetic core for the choke coil and the transformer, any material having a soft magnetic property is effective.
iZn-based ferrite, dust core, silicon steel plate, amorphous and the like are used.

There is no particular limitation on the shape of the magnetic core 21, and the shape of the magnetic core 21 is not particularly limited.
The present invention can be applied to a magnetic core having any shape such as an EI core.

A gap G is provided in at least one or more of the magnetic paths of these cores, and a permanent magnet 23 is disposed so as to face this gap G and in an empty space RS within the maximum outer shape of the inductor.

There is no particular limitation on the gap length. If the gap length is too small, the DC superposition characteristic deteriorates, and if the gap length is too wide, the magnetic permeability is too low. Therefore, the gap length to be inserted naturally is determined. .

The required characteristics of the permanent magnet 23 are as follows. With respect to the intrinsic coercive force, if the coercive force is less than 10 KOe, the coercive force disappears due to the DC magnetic field applied to the magnetic core. The larger the value, the better, but if it is 1 Ω · cm or more, it does not become a major factor in core loss deterioration. When the average maximum particle size of the powder is 50 μm or more, the core loss characteristics deteriorate. Therefore, the maximum particle size of the powder is desirably 50 μm or less, and the minimum particle size is 2.
When the thickness is 5 μm or less, the decrease in magnetization due to the oxidation of the powder during powder heat treatment and reflow becomes remarkable.

Table 1 below shows the characteristics of various soft magnetic materials applicable to the magnetic core 21. Table 2 below shows the characteristics of various hard magnetic materials applicable to the permanent magnet 23.

[0029]

[Table 1]

[0030]

[Table 2]

[Embodiment 2] FIGS. 3A to 3E are views for explaining an inductor according to the present embodiment, and FIGS. 4A to 4E show the configuration of the present inductor. FIG.

Referring to FIGS. 3A to 3E, in the present inductor, a coil is wound around a core side of a magnetic core 31 made of a soft magnetic material having a magnetic air gap (gap) G. This is an inductor in which a permanent magnet is disposed so as to face the gap G. However, in this drawing, the permanent magnet is not shown for convenience of explanation. In the present inductor, the magnetic core 31 is composed of two substantially E-shaped core pieces.
Each core side end face is abutted, and furthermore, it is arranged horizontally. Further, the present inductor has a base 34 serving as a bobbin in which a coil 32 is wound and a terminal 35 to which a winding end of the coil 32 is electrically connected is implanted.

In the drawing, the areas denoted by reference numerals RS1 and RS2 include the base 34, the magnetic core 31, and the coil 32, but exclude the permanent magnets and fall within the maximum outer shape of the inductor defined by the components of the present inductor. Indicates an empty space (or invalid space). Even if some parts are arranged in the empty spaces RS1 and RS2,
It goes without saying that when the present inductor is mounted on an electronic circuit board through a reflow process or the like, there is no portion protruding from the outer shape of the inductor, and therefore there is no interference with adjacent components.

Referring to FIGS. 4A to 4E, the four permanent magnets 33 face the gap G and include the base 34, the magnetic core 31, and the coil 32, while the permanent magnets 33 33 is an empty space RS1 within the maximum outer shape of the inductor defined by the components of the present inductor, excluding
RS2 (FIG. 3).

The magnetic core 31 is made of Mn-Zn ferrite, has a magnetic permeability of 4 × 10 ⁻³ H / m, and a magnetic path length of 0.1 × 10 ⁻³ H / m.
02 m, and the effective area is 5 × 10 ⁻⁶ m ² .

On the other hand, the permanent magnet 33 is a sintered Ba-based ferrite magnet and has characteristics of a coercive force of 100 A / m or more and a residual magnetic flux density of 0.4 T.

[Embodiment 3] FIGS. 5A to 5D are views for explaining an inductor according to the present embodiment, and FIGS. 2A to 2D show the configuration of the present inductor. FIG.

Referring to FIGS. 5A to 5D, in the present inductor, a coil is wound around a core side of a magnetic core 41 made of a soft magnetic material having a magnetic gap (gap) G. This is an inductor in which a permanent magnet is disposed so as to face the gap G. However, in this drawing, the permanent magnet is not shown for convenience of explanation. In the present inductor, the magnetic core 41 is composed of two substantially E-shaped core pieces.
The cores are arranged so that the end faces of the cores are attached to each other, and are further disposed vertically. Furthermore, the present inductor has a bobbin base 44 on which a coil 45 is wound and a terminal 45 to which the winding end of the coil 42 is electrically connected is implanted.

In the figure, a region denoted by reference numeral RS4 includes a base 44, a magnetic core 41, and a coil 42,
Empty space within the maximum outer shape of the inductor specified by the components of this inductor excluding permanent magnets (or
Invalid space). Even if some component is arranged in the empty space RS4, when the present inductor is mounted on an electronic circuit board through a reflow process or the like, a portion protruding from the outer shape of the inductor does not occur. Needless to say, it does not interfere with the communication.

Referring to FIGS. 6A to 6D, the four permanent magnets 43 face the gap G and include the base 44, the magnetic core 41, and the coil 42, while the permanent magnets 43 43 is a vacant space RS4 within the maximum outer shape of the inductor specified by the components of the present inductor, excluding 43
(FIG. 5).

The magnetic core 41 is made of Mn-Zn ferrite, has a magnetic permeability of 4 × 10 ⁻³ H / m, and a magnetic path length of 0.1 × 10 ⁻³ H / m.
02 m, and the effective area is 5 × 10 ⁻⁶ m ² .

On the other hand, the permanent magnet 43 is a sintered Ba-based ferrite magnet and has characteristics such that the coercive force is 100 A / m or more and the residual magnetic flux density is 0.4 T.

[Fourth Embodiment] FIGS. 7A to 7D are views for explaining an inductor according to the present embodiment, and FIGS. 8A to 8D show the configuration of the present inductor. FIG.

Referring to FIGS. 7A to 7D, in the present inductor, a coil is wound around a core side of a magnetic core 51 made of a soft magnetic material having a magnetic gap (gap) G. This is an inductor in which a permanent magnet is disposed so as to face the gap G. However, in this drawing, the permanent magnet is not shown for convenience of explanation. In the present inductor, the magnetic core 51 is composed of two substantially cylindrical core pieces.
And the end faces of each,
It is configured to overlap vertically and is also called a pot type. A coil 52 is wound around the core pieces of the magnetic core 51 in the circumferential direction. Further, the present inductor has a base 54 on which a terminal 55 to which a winding end of a coil 52 is electrically connected is implanted.

In the figure, a region denoted by reference numeral RS5 includes a base 54, a magnetic core 51, and a coil 52, while
Empty space within the maximum outer shape of the inductor specified by the components of this inductor excluding permanent magnets (or
Invalid space). Even if some components are arranged in the empty space RS5, when the present inductor is mounted on an electronic circuit board through a reflow process or the like, a portion protruding from the outer shape of the inductor does not occur. Needless to say, it does not interfere with the communication.

Referring to FIGS. 8A to 8D, the four permanent magnets 53 face the gap G and include a base 54, a magnetic core 51, and a coil 52. 53 is an empty space RS5 within the maximum outer shape of the inductor specified by the components of the present inductor, excluding 53
(FIG. 7).

The magnetic core 51 is made of Mn—Zn ferrite and has a magnetic permeability of 4 × 10 ⁻³ H / m.

On the other hand, the permanent magnet 53 is a sintered Ba-based ferrite magnet having a characteristic that the coercive force is 100 A / m or more and the residual magnetic flux density is 0.4 T.

[Fifth Embodiment] FIGS. 9A to 9D are views for explaining an inductor according to the present embodiment, and FIGS. 10A to 10D show the configuration of the present inductor. FIG.

Referring to FIGS. 9A to 9D, in the present inductor, a coil is wound around a core side of a magnetic core 61 made of a soft magnetic material having a magnetic air gap (gap) G. This is an inductor in which a permanent magnet is disposed so as to face the gap G. However, in this drawing, the permanent magnet is not shown for convenience of explanation. In the present inductor, the magnetic core 61 is composed of two substantially U-shaped core pieces.
The cores are arranged so that the end faces of the cores are attached to each other, and are further disposed vertically. Further, the present inductor has a bobbin 64 around which a coil 62 is wound. The winding end of the coil 62 is derived from the present inductor as a lead terminal.

In the figure, a region denoted by reference numeral RS7 includes a bobbin 64, a magnetic core 61, and a coil 62,
Empty space within the maximum outer shape of the inductor specified by the components of this inductor excluding permanent magnets (or
Invalid space). Even if some components are arranged in the empty space RS7, when the present inductor is mounted on an electronic circuit board through a reflow process or the like, no portion protruding from the outer shape of the inductor occurs, and therefore, the adjacent components are not provided. Needless to say, it does not interfere with the communication.

Referring to FIGS. 10A to 10D, the two permanent magnets 63 face the gap G and include the bobbin 64, the magnetic core 61, and the coil 62.
An empty space RS7 within the maximum outer shape of the inductor specified by the components of the present inductor excluding the permanent magnet 63
(FIG. 9).

The magnetic core 61 is made of Mn-Zn ferrite and has a shape having a magnetic permeability of 4 × 10 ⁻³ H / m and an effective area of 5 × 10 ⁻⁶ m ² .

On the other hand, the permanent magnet 63 is a sintered Ba-based ferrite magnet and has a characteristic that the coercive force is 100 A / m or more and the residual magnetic flux density is 0.4 T.

Sixth Embodiment FIGS. 11A to 11D are views for explaining an inductor according to the present embodiment, and FIGS. 12A to 12D show the configuration of the inductor. FIG.

Referring to FIGS. 11A to 11D, in the present inductor, a coil is wound around a core side of a magnetic core 71 made of a soft magnetic material having a magnetic air gap (gap) G.
Further, this is an inductor in which a permanent magnet is disposed so as to face the gap G. However, in this drawing, the permanent magnet is not shown for convenience of explanation. In the present inductor, each of the magnetic cores 71 is composed of two substantially U-shaped core pieces.
The cores are arranged so that the end faces of the cores are attached to each other, and are further disposed vertically. Further, the present inductor has a base 74 also serving as a bobbin, on which a terminal 75 to which the coil 72 is wound and a winding end of the coil 72 is electrically connected is implanted.

In the figure, a region denoted by reference numeral RS8 includes a base 74, a magnetic core 71, and a coil 72,
Empty space within the maximum outer shape of the inductor specified by the components of this inductor excluding permanent magnets (or
Invalid space). Even if some components are arranged in the empty space RS8, when the present inductor is mounted on an electronic circuit board through a reflow process or the like, a portion protruding from the outer shape of the inductor does not occur. Needless to say, it does not interfere with the communication.

Referring to FIGS. 12A to 12D, the two permanent magnets 73 face the gap G and include a base 74, a magnetic core 71, and a coil 72.
Empty space RS8 within the maximum outer shape of the inductor specified by the components of the present inductor excluding the permanent magnet 73
(FIG. 11).

The magnetic core 71 is made of Mn-Zn ferrite and has a shape having a magnetic permeability of 4 × 10 ⁻³ H / m and an effective area of 5 × 10 ⁻⁶ m ² .

On the other hand, the permanent magnet 73 is a sintered Ba-based ferrite magnet and has characteristics such that the coercive force is 100 A / m or more and the residual magnetic flux density is 0.4 T.

[0061]

According to the inductor of the present invention, since the permanent magnet includes the magnetic core and the coil, the permanent magnet is disposed in an empty space within the maximum outer shape of the inductor defined by the components of the inductor excluding the permanent magnet. Although the so-called mounting space required to mount and mount the inductor as a device on an electronic circuit board or in the housing of an electronic device is the same as the conventional inductor without permanent magnets, High magnetic inductance value can be maintained even at a large current value, and eddy current loss and abnormal current heating are unlikely to occur, so permanent magnets are not demagnetized. Is excellent. Since the mounting space does not increase, it is suitable for use in electronic devices that are desired to be reduced in size, thickness, and weight.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a configuration of an inductor according to a first embodiment of the present invention, where (a), (b), and (c) are a perspective view, a bottom view, and a side view of the inductor, respectively. It is.

FIG. 2 is a diagram showing a configuration of the inductor according to the first embodiment of the present invention, wherein (a), (b), and (c) are a perspective view, a bottom view, and a side view of the inductor, respectively.

FIGS. 3A and 3B are diagrams for explaining a configuration of an inductor according to a second embodiment of the present invention, wherein FIGS.
(D) and (e) are a perspective view, a bottom view, a front view, a top view, and a side view of the inductor, respectively.

FIG. 4 is a diagram showing a configuration of an inductor according to a second embodiment of the present invention, wherein (a), (b), (c), (d), and (e) are a perspective view and a bottom view of the inductor, respectively; Figure,
It is a front view, a top view, and a side view.

FIGS. 5A and 5B are diagrams for explaining a configuration of an inductor according to a third embodiment of the present invention, wherein FIGS.
And (d) are a perspective view, a top view, a front view, and a side view of the inductor, respectively.

FIG. 6 is a diagram showing a configuration of an inductor according to a third embodiment of the present invention, wherein (a), (b), (c), and (d) are a perspective view, a top view, and a front view of the inductor, respectively. , And a side view.

FIGS. 7A and 7B are diagrams for explaining a configuration of an inductor according to a fourth embodiment of the present invention, wherein FIGS.
And (d) are a perspective view, a top view, a front view, and a side view of the inductor, respectively.

FIG. 8 is a diagram showing a configuration of an inductor according to a fourth embodiment of the present invention, wherein (a), (b), (c), and (d) are a perspective view, a top view, and a front view of the inductor, respectively. , And a side view.

FIG. 9 is a diagram for explaining a configuration of an inductor according to a fifth embodiment of the present invention, wherein (a), (b), (c),
And (d) are a perspective view, a top view, a front view, and a side view of the inductor, respectively.

FIG. 10 is a diagram showing a configuration of an inductor according to a fifth embodiment of the present invention, where (a), (b), (c), and (d) are a perspective view, a top view, and a front view of the inductor, respectively. , And a side view.

FIGS. 11A and 11B are diagrams for explaining a configuration of an inductor according to a sixth embodiment of the present invention, wherein FIGS.
(C) and (d) are a perspective view, a top view, a front view, and a side view of the inductor, respectively.

FIG. 12 is a diagram showing a configuration of an inductor according to a sixth embodiment of the present invention, where (a), (b), (c), and (d) are a perspective view, a top view, and a front view of the inductor, respectively. , And a side view.

FIG. 13 is a diagram showing DC superposition characteristics of the inductor according to the first embodiment of the present invention and a conventional inductor having no permanent magnet as a comparative example.

FIG. 14 is a diagram showing a configuration of a conventional inductor;
(A), (b), (c), and (d) are a perspective view, a top view, a front view, and a side view of the inductor, respectively.

[Explanation of symbols]

11, 21, 31, 41, 51, 61, 71 Magnetic core 12, 22, 32, 42, 52, 62, 72 Coil 13, 23, 33, 43, 53, 63, 73 Permanent magnets 24, 34, 44, 54, 74 base 14, 64 bobbin 25, 35, 45, 55, 75 terminal RS, RS1, RS2, RS4, RS5, RS7, RS
8 free space (ineffective space)

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kazuyuki Okita 6-7-1, Koriyama, Taishiro-ku, Sendai City, Miyagi Prefecture Tokinnai Co., Ltd. (72) Inventor Teruhiko Fujiwara 6-7-1, Koriyama, Taishiro-ku, Sendai City, Miyagi Prefecture No. Tokinnai F-term (reference) 5E041 AA02 AB01 AB02 BD01 BD03 CA01 HB17 NN06

Claims (5)

[Claims] 1. An inductor in which a coil is wound around a core side of a magnetic core having a magnetic gap, and a permanent magnet is arranged so as to face the magnetic gap. And an inductor, wherein the inductor is disposed in an empty space within a maximum outer shape of the inductor defined by components of the inductor except for the permanent magnet. 2. The inductor further includes a base on which a terminal to which a winding end of the coil is electrically connected is implanted, and the permanent magnet includes the base, the magnetic core, and the coil. 2. The inductor according to claim 1, wherein the inductor is disposed in an empty space within a maximum outer shape of the inductor defined by components of the inductor excluding the permanent magnet. 3. 3. The inductor further includes a bobbin around which the coil is wound, and the permanent magnet includes a bobbin,
3. The inductor according to claim 1, wherein the inductor is disposed in an empty space that includes the magnetic core and the coil but excludes the permanent magnet and that is within a maximum outer shape of the inductor defined by components of the inductor. 4. 4. The permanent magnet has a specific coercive force of 10 KO.
e and the average particle size of the powder having a Tc of 500 ° C. or more is 2.5
The inductor according to any one of claims 1 to 3, wherein the inductor is a bonded magnet having a volume ratio of a rare earth magnet powder having a volume of 30 m or more and a specific resistance of 1? Cm or more. 5. The magnetic core is made of MnZn or Ni.
The inductor according to any one of claims 1 to 4, wherein the inductor is made of Zn-based ferrite, silicon steel plate, or amorphous.