【発明の詳細な説明】（技術分野）本発明はインダクタ用磁心に関し、特に、電子機器のイ
ンダクタンス素子として用いられる固定コイルやフィル
ターなどの磁心となる、外部圧力に対してインダクタン
ス変化の小さい酸化物磁心に関する。Detailed Description of the Invention (Technical Field) The present invention relates to a magnetic core for an inductor, and in particular to an oxide that has a small change in inductance with respect to external pressure and is used as a magnetic core for fixed coils and filters used as inductance elements in electronic equipment. Regarding magnetic core.
（従来技術とその問題点）テレビ、ビデオレコーダ、自動車電話等の電子機器には
インダクタンス素子として酸化物磁性材料であるフェラ
イトコアを磁心とするフィルターや固定コイルが大量に
用いられている。固定コイルは機械的強度の保持や温度
等の外部環境にたいして信頼性を得るためドラム型など
の磁心に巻き線を施した後に、樹脂の塗装や成形が行な
われる。(Prior art and its problems) Electronic devices such as televisions, video recorders, and car phones use a large number of filters and fixed coils whose magnetic cores are ferrite cores made of oxide magnetic material as inductance elements. Fixed coils are coated with resin or molded after winding around a magnetic core such as a drum in order to maintain mechanical strength and obtain reliability against external environments such as temperature.
しかし、磁心に用いられるフェライトコアは外部応力に
たいしてインダクタンスが変化しやすいという欠点を有
しており、特に樹脂で外装する場合は樹脂の収縮力によ
りインダクタンスの変化が起き、インダクタンス公差の
小さい高品質のものが得られない問題点があった。However, the ferrite core used in magnetic cores has the disadvantage that its inductance easily changes in response to external stress. Particularly when the ferrite core is coated with resin, the inductance changes due to the shrinkage force of the resin. There was a problem with not being able to get anything.
したがって、電子機器において高精度のインダクタンス
とする場合はインダクタンス微調整の可能なネジ型の磁
心が用いられていた。しかし可変コイルは可変機構を必
要とするため、大型化が避けられず、電子機器の小型化
、薄型化、ＳＭＴ化等の設計上の要求に応えられなかっ
た。また可変コイルの調整やインダクタンスの測定など
の面倒な工程を必要とした。Therefore, in order to obtain high-precision inductance in electronic equipment, a screw-shaped magnetic core that allows fine adjustment of the inductance has been used. However, since the variable coil requires a variable mechanism, it is unavoidable to increase its size, and it has not been able to meet design demands such as miniaturization, thinning, and SMT of electronic equipment. It also required cumbersome processes such as adjusting the variable coil and measuring inductance.
したがって、外部応力にたいしてインダクタンスの変化
の小さい磁性材料が実現されれば、小型で無調整の特徴
を有する固定コイルやフィルター用インダクタを構成で
きることは明らかであり、実際各種の努力が成されてい
るが、残念なことに現在までのところ実現されていない
。Therefore, it is clear that if a magnetic material with a small change in inductance in response to external stress is realized, it will be possible to construct fixed coils and filter inductors that are small and have non-adjustable characteristics, and various efforts are being made to do so. Unfortunately, this has not been realized to date.
（発明の目的）したがって、本発明の目的は、常時外部応力の加わる状
態で使用される磁心であって、外部応力に変動があって
もインダクタンス変化の小さいインダクタを構成しつる
酸化物磁心を提供することにある。(Object of the Invention) Therefore, an object of the present invention is to provide a magnetic core that is used under constant external stress and that constitutes an inductor with small changes in inductance even when the external stress fluctuates. It's about doing.
（発明の概要）本発明の前記目的は、Ｎｉを必須成分として含有する磁
性酸化物フェライト材料に添加物としてＢｉｇ Ｏ３，
Ｖ２０ｇ （７）少なくとも１種を０．５〜５重量％含
有させた焼結体からなることを特徴とする、外部応力下
に使用されるインダクタ用磁心により達成される。ここ
に、磁性酸化物フェライトは従来公知の軟磁性材料であ
り、これにＢ ｉｚ Ｏａ 、 Ｖ２０＋１の少なくと
も１種を含有させることにより外部応力の変化にたいし
てインダクタンス変化の著しく小さいインダクタが構成
できることになった。(Summary of the Invention) The object of the present invention is to add Big O3, as an additive to a magnetic oxide ferrite material containing Ni as an essential component.
V20g (7) This is achieved by a magnetic core for an inductor used under external stress, which is made of a sintered body containing 0.5 to 5% by weight of at least one kind. Here, the magnetic oxide ferrite is a conventionally known soft magnetic material, and by incorporating at least one of B iz Oa and V20+1 into it, an inductor with a significantly small change in inductance with respect to changes in external stress can be constructed. .
本発明によれば、例えば樹脂による外装を行なうときの
塗装厚さ等の条件変化があっても、磁心の磁気特性は安
定に保たれるから、工程管理が容易になり、微調整ネジ
やトリミングが不要になるなど、インダクタの製造、特
性の安定性などの点で大きな利益が得られる。According to the present invention, the magnetic properties of the magnetic core are kept stable even if there are changes in conditions such as coating thickness when coating with resin, making process control easier, and fine adjustment screws and trimming. There are significant benefits in terms of inductor manufacturing and stability of characteristics, such as eliminating the need for inductors.
（発明の構成の具体的な説明）本発明は、磁心用として一般に用いられているＮｉ−Ｚ
ｎ系フェライト、Ｎｉ−Ｃｕ−Ｚｎ系フェライト、Ｎｉ
−Ｃｕ−Ｍｇ系フェライト、Ｎｉ−Ｍ ｎ −Ｃｕ −
Ｚ ｎ系フェライト等の、Ｎｉを必須成分として含有す
る磁性酸化物フェライト材料に添加物としてＢ ｉｚ
０３ 、Ｖｚ Ｏｓの少なくとも１ ｆｆｆｌを０．５
〜５重量％含有させた焼結体からなることを特徴とする
、外部応力下に使用されるインダクタ用磁心である。こ
の系統の酸化物フェライトは、従来から高抵抗で、高周
波側においても使用し得る軟磁性体として広く用いられ
ている材料であるもので、好ましい組成や磁気特性は良
く知られているので、ここでは実施例は別として具体的
には記載しない。(Specific description of the structure of the invention) The present invention is based on Ni-Z, which is generally used for magnetic cores.
n-based ferrite, Ni-Cu-Zn-based ferrite, Ni
-Cu-Mg ferrite, Ni-Mn-Cu-
Biz as an additive to magnetic oxide ferrite materials containing Ni as an essential component, such as Z n-based ferrite.
03, Vz Os at least 1 fffl 0.5
This is a magnetic core for an inductor used under external stress, characterized by being made of a sintered body containing ~5% by weight. This type of oxide ferrite is a material that has been widely used as a soft magnetic material that has high resistance and can be used even on the high frequency side, and its preferable composition and magnetic properties are well known, so we will discuss it here. Now, apart from examples, specific details will not be described.
Ｂ ｉｚ ０３ 、Ｖ２Ｏ３の添加は本発明の磁心を用
いたインダクタにおけるインダクタンスの安定性に欠く
ことのできない必須の構成要件である。The addition of B iz 03 and V2O3 is an essential component indispensable for the stability of inductance in the inductor using the magnetic core of the present invention.
Ｂ ｉ ２０．の添加は０．５重量％以上であり、好ま
しくは１％以上であり、更に好ましくは２％（重量）で
ある。一方、Ｖ２Ｏ５の添加は０゜５重量％以上であり
、好ましくは１％以上であり、更に好ましくは２％（重
量）である。また、これらを組合せて用いる場合には総
量で０．５％以上の量で用いる。従来のフェライト磁心
は外装樹脂等から加わる外部応力のバラツキに対してイ
ンダクタンスの一７％以上の変動も稀では無かったが、
本発明によれば、０．５重量％以上の転化において−３
，５％以内の改善が得られ、Ｂ１□Ｏ５含有率が２％以
上になれば１．５％以内の変化率さえ得られる。ｖ、Ｏ
Ｂ含有率が２％以上になれば１％以内の変化率さえ得ら
れる。なおりｉａ Ｏｓ 、Ｖ２０ｇの含有率の上限は
臨界的な意味を持たず、５％のように大量に用いてもよ
いが、透磁率が低下するので実用上５％以下の量に制限
する。なお透磁率の低下による特性の低下は巻線の巻き
数を増やすことで容易に調整しつる。B i 20. The addition amount is 0.5% by weight or more, preferably 1% or more, and more preferably 2% (by weight). On the other hand, the amount of V2O5 added is 0.5% by weight or more, preferably 1% or more, and more preferably 2% (by weight). Moreover, when these are used in combination, they are used in a total amount of 0.5% or more. With conventional ferrite magnetic cores, it was not uncommon for the inductance to fluctuate by more than 17% due to variations in external stress applied from the exterior resin, etc.
According to the invention, at a conversion of 0.5% by weight or more -3
, an improvement of within 5% can be obtained, and if the B1□O5 content is 2% or more, a change rate of even within 1.5% can be obtained. v, O
If the B content is 2% or more, a rate of change within 1% can be obtained. The upper limit of the content of Naori ia Os and V20g does not have any critical meaning and may be used in large amounts such as 5%, but since the magnetic permeability decreases, it is practically limited to an amount of 5% or less. Note that the decrease in characteristics due to the decrease in magnetic permeability can be easily adjusted by increasing the number of turns of the winding.
本発明の効果が得られる理由については充分に解明され
ていないが、Ｂ １２０３ 、Ｖｚ Ｏｓを含有させ焼
結フェライトを製造する過程においてＢ ｉｉ Ｏｓ
、Ｖｚ Ｏｓが結晶粒界に析出し、これが外部応力の吸
収を容易にすることにより、磁気特性が応力にたいして
安定化するものと思われる。The reason why the effects of the present invention are obtained is not fully elucidated, but in the process of manufacturing sintered ferrite containing B 1203 and Vz Os, B ii Os
, Vz Os precipitates at grain boundaries, which facilitates the absorption of external stress, thereby stabilizing the magnetic properties against stress.
以下に本発明の実施例を詳しく説明する。Examples of the present invention will be described in detail below.
’ ＩＩ Ｂｉ ２０ｉ の１、 ロク
）従来慣用されている方法で製作されたｍｏｌ比でＦ
ｅ２Ｏ３：ＮｉＯ：ＣｕＯ：Ｚｎ０＝４９゜： ２６
： ５ ： ２０の成分のＮｉ−Ｃｕ−Ｚｎ系フェライ
トにＢｉ２５３を０〜５ｗｔ％の範囲で添加し、混合後
、外形１０ｍｍ、長さ４０ｍｍの丸棒コアを加圧成形し
、９５０〜１１００℃で２時間焼成して酸化物磁性フェ
ライトを得た。得られた丸棒コアの中央部に外形０．３
ｍｍのワイヤーを１０回巻線した後、ＬＣＲメーターに
おいてインダクタンスを測定し、次式でインダクタンス
の変化率を算出した。ただし圧力は約５００ｋｇ／ｃｍ
２を用いた。'II Bi 20i No. 1, Roku
) F at the molar ratio produced by the conventionally used method
e2O3:NiO:CuO:Zn0=49°: 26
: 5 : Bi253 was added in the range of 0 to 5 wt% to the Ni-Cu-Zn ferrite having the components of 20, and after mixing, a round bar core with an outer diameter of 10 mm and a length of 40 mm was press-formed at 950 to 1100 ° C. After firing for 2 hours, an oxide magnetic ferrite was obtained. The central part of the obtained round bar core has an outer diameter of 0.3
After winding a mm wire 10 times, the inductance was measured using an LCR meter, and the rate of change in inductance was calculated using the following formula. However, the pressure is approximately 500kg/cm
2 was used.
インダクタンスの変化率（％）＝（加圧状態時のインダクタンス−加圧前のインダクタ
ンス）／加圧前のインダクタンスその結果を第１図に示
した。Rate of change in inductance (%) = (Inductance in pressurized state - Inductance before pressurization)/Inductance before pressurization The results are shown in FIG.
それによるとＢｉ２Ｏ３添加ｆｆｉ Ｏｗ ｔ％におい
ては−７，０％のインダクタンス変化が生じるが、Ｂｉ
’ｚＯ３の添加量が増加するにつれて変化量が小さくな
り、特に１ｗｔ％以上の添加量において著しくインダク
タンス変化量が小さくなることが分かる。According to this, when Bi2O3 is added ffi Ow t%, an inductance change of -7.0% occurs;
It can be seen that as the amount of zO3 added increases, the amount of change in inductance becomes smaller, and especially when the amount of addition is 1 wt% or more, the amount of change in inductance becomes significantly smaller.
また図の結果より５ｗｔ％以上においても改善効果が推
定できるが、インダクタンス変化が増大する傾向があり
、また透磁率は減少するから、実用上５ｗｔ％迄の添加
量が有用である。Further, from the results shown in the figure, an improvement effect can be estimated even when the amount is 5 wt% or more, but since the inductance change tends to increase and the magnetic permeability decreases, it is practically useful to add up to 5 wt%.
’Ｌノ１２ ｖ２ｏｓの、１、口勿果）実施例１と同
じ成分比のＮｉ−Ｃｕ−Ｚｎ系フェライトにｖ２０．を
０〜５ｗｔ％の範囲で添加し、混合後、外形１０ｍｍ、
長さ４０ｍｍの丸棒コアを加圧成形し、９５０〜１１ｏ
Ｏ℃で２時間焼成して酸化物磁性フェライトを得た。得
られた丸棒コアの中央部に外形０．３ｍｍのワイヤーを
１０回巻線した後、ＬＣＲメーターにおいてインダクタ
ンスを測定し、インダクタンスの変化率を算出した。結
果を第１図に示す。'L no 12 v2os, 1, Kuchimakkou) v20. was added in a range of 0 to 5 wt%, and after mixing, the outer diameter was 10 mm,
Pressure mold a round bar core with a length of 40 mm and heat it at 950~11o.
An oxide magnetic ferrite was obtained by firing at 0° C. for 2 hours. After winding a wire with an outer diameter of 0.3 mm 10 times around the center of the obtained round bar core, the inductance was measured using an LCR meter, and the rate of change in inductance was calculated. The results are shown in Figure 1.
それによるとＶａ Ｏｓ添加ｆｉ Ｏｗ ｔ％において
は一７％のインダクタンス変化が生じるが、■２０、の
添加量が増加するにつれて変化量が小さくなり、特に１
ｗｔ％以上の添加量において著しくインダクタンス変化
量が小さくなることが分かる。According to this, an inductance change of 7% occurs when Va Os is added fi Ow t%, but as the amount of addition of 20 increases, the amount of change becomes smaller, and especially
It can be seen that the amount of change in inductance becomes significantly smaller when the amount added is greater than wt%.
また図の結果より５ｗｔ％以上においても改善効果が推
定できるが、インダクタンス変化が増大する傾向があり
、また透磁率は減少するから、実用上５ｗｔ％迄の添加
量が有用である。Further, from the results shown in the figure, an improvement effect can be estimated even when the amount is 5 wt% or more, but since the inductance change tends to increase and the magnetic permeability decreases, it is practically useful to add up to 5 wt%.
１３ Ｂｊｚ Ｏｓ 、Ｖａ ０ｇ ”−１）実施
例１と同じ成分比のＮｉ−Ｃｕ−Ｚｎ系フエライトニＢ
ｉ ｘ Ｏｓ 、Ｖａ ０ｇを１：１（７）割合で添
加し、総ｆｆ１０．５％以上添加し、実施例１と同様に
処理し、実施例１と同様に測定したところ、実施例１と
ほとんど同一の結果を得た。13 Bjz Os , Va 0g ''-1) Ni-Cu-Zn ferrite Ni B with the same component ratio as Example 1
i x Os and 0 g of Va were added at a ratio of 1:1 (7), and the total ff was added at 10.5% or more, treated in the same manner as in Example 1, and measured in the same manner as in Example 1. Almost identical results were obtained.
！４− づ゛での９ ）実施例１．２．３で得られたＢｉ、Ｏ，、Ｖ２Ｏ６及び
それらの１＝１の組合せでおのおの３重量％添加の本発
明品と従来から市販されているＮｉ−Ｃｕ−Ｚｎ系フェ
ライトとの実用形状での比較を行なった。本発明品と従
来品をそれぞれ外形４ｍｍ、長さ３ｍｍのドラム型磁心
を製作し、インダクタンス値３０μＨが得られるように
試料数１００個を巻線した後、エポキシ樹脂で１．５ｍ
ｍの厚さに塗装し、乾燥し、焼き付は後にインダクタン
スを測定し、そのインダクタンスの変化率を調べた。従
来品のインダクタンス変化率の平均値は−６，５％でバ
ラツキ範囲は５．４μＨにたいして、実施例１．２．３
の本発明品はインダクタンス変化率の平均値はそれぞれ
一〇、７５、−０．８８、−０．８０％でバラツキ範囲
はそれぞれ１．８．２．１，２．０μＨと著しく改善効
果が見出された。! 4-9) Bi, O, V2O6 obtained in Example 1.2.3 and the 1=1 combination of the present invention with 3% by weight of each added, and the conventional commercially available product. A comparison was made in a practical shape with Ni-Cu-Zn ferrite. Drum-shaped magnetic cores with an outer diameter of 4 mm and a length of 3 mm were manufactured for the inventive product and the conventional product, respectively, and after winding 100 samples to obtain an inductance value of 30 μH, 1.5 m of epoxy resin was formed.
It was coated to a thickness of m, dried, and after baking, the inductance was measured and the rate of change in inductance was investigated. The average value of the inductance change rate of the conventional product is -6.5% and the variation range is 5.4μH, whereas Example 1.2.3
In the products of the present invention, the average value of the inductance change rate is 10, 75, -0.88, and -0.80%, respectively, and the variation range is 1.8, 2.1, and 2.0 μH, respectively, which shows a remarkable improvement effect. Served.
即ち、本発明品は樹脂の収縮による外部応力に対してき
わめて安定なことが分かる。That is, it can be seen that the product of the present invention is extremely stable against external stress caused by resin contraction.
この結果により本発明品の実用状態での有用性が確認さ
れた。These results confirmed the usefulness of the product of the present invention in practical use.
（作用効果のまとめ）以上のように本発明による磁性酸化物磁心は樹脂などか
ら加わる外部応力下に使用される磁心としてきわめて優
れた素材であり、Ｂｉａｓ３、Ｖ２Ｏ３の添加により外
部応力にたいしてきわめてインダクタンス変化の小さい
ものが提供でき、フィルター、固定コイル等の磁心とし
て優れた特性を発揮するものである。(Summary of effects) As described above, the magnetic oxide core according to the present invention is an extremely excellent material for use as a magnetic core under external stress applied from resin, etc., and the addition of Bias3 and V2O3 significantly reduces the inductance change in response to external stress. It can be provided with a small size and exhibits excellent characteristics as a magnetic core for filters, fixed coils, etc.
第１図はＢｉｚＯｓ、Ｖｚ○６の添加量が外部応力に対
するインダクタンス変化率に及ぼす作用を示すグラフで
ある。、−′代理人の氏名 倉 内 基 ’Ａ、’Ｈ’；’ｊ’、：
、’−ｆ！・、−一ユし第１図添加ｉFIG. 1 is a graph showing the effects of the added amounts of BizOs and Vz○6 on the rate of change in inductance with respect to external stress. ,-' Name of agent Motoki Kurauchi 'A,'H';'j',:
,'-f!・, -1 yushi Figure 1 addition i
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63000673AJP3123605B2 (en) | 1988-01-07 | 1988-01-07 | Magnetic core for inductor |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63000673AJP3123605B2 (en) | 1988-01-07 | 1988-01-07 | Magnetic core for inductor |
| Publication Number | Publication Date |
|---|---|
| JPH01179402Atrue JPH01179402A (en) | 1989-07-17 |
| JP3123605B2 JP3123605B2 (en) | 2001-01-15 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63000673AExpired - Fee RelatedJP3123605B2 (en) | 1988-01-07 | 1988-01-07 | Magnetic core for inductor |
| Country | Link |
|---|---|
| JP (1) | JP3123605B2 (en) |
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| EP0891955A1 (en)* | 1997-07-16 | 1999-01-20 | TDK Corporation | Ferrite and inductor |
| US6068786A (en)* | 1997-11-25 | 2000-05-30 | Darfon Electronics Corp. | Low-fire ferrite composition and a process for manufacturing ceramic articles using the said composition |
| US6583699B2 (en) | 2000-10-31 | 2003-06-24 | Tdk Corporation | Magnetic material and inductor |
| US6741154B2 (en) | 2000-12-25 | 2004-05-25 | Tdk Corporation | Low-temperature burnt ferrite material and ferrite parts using the same |
| US7892446B2 (en) | 2005-09-13 | 2011-02-22 | Hitachi Metals, Ltd. | Ferrite material |
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|---|---|---|---|---|
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| JPS60210572A (en)* | 1984-04-04 | 1985-10-23 | 日本電気株式会社 | Low temperature sintered oxide magnetic material |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS5916307A (en)* | 1982-07-19 | 1984-01-27 | Nippon Ferrite Ltd | Ferrite core for rotary transformer and manufacture thereof |
| JPS60210572A (en)* | 1984-04-04 | 1985-10-23 | 日本電気株式会社 | Low temperature sintered oxide magnetic material |
| JPS63260006A (en)* | 1987-04-16 | 1988-10-27 | Nippon Ferrite Ltd | High density magnetic material |
| JPH01103953A (en)* | 1987-10-14 | 1989-04-21 | Nippon Ferrite Ltd | Thermal shock resistant ferrite material |
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| KR970051500A (en)* | 1995-12-28 | 1997-07-29 | 김익명 | Magnesium-Copper-Zinc Oxide Magnetic Materials |
| EP0891955A1 (en)* | 1997-07-16 | 1999-01-20 | TDK Corporation | Ferrite and inductor |
| US6033594A (en)* | 1997-07-16 | 2000-03-07 | Tdk Corporation | Ferrite and inductor |
| US6068786A (en)* | 1997-11-25 | 2000-05-30 | Darfon Electronics Corp. | Low-fire ferrite composition and a process for manufacturing ceramic articles using the said composition |
| US6583699B2 (en) | 2000-10-31 | 2003-06-24 | Tdk Corporation | Magnetic material and inductor |
| US6741154B2 (en) | 2000-12-25 | 2004-05-25 | Tdk Corporation | Low-temperature burnt ferrite material and ferrite parts using the same |
| EP2248783A2 (en) | 2000-12-25 | 2010-11-10 | TDK Corporation | Low temperature sintered ferrite material and ferrite parts using the same |
| US7892446B2 (en) | 2005-09-13 | 2011-02-22 | Hitachi Metals, Ltd. | Ferrite material |
| Publication number | Publication date |
|---|---|
| JP3123605B2 (en) | 2001-01-15 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |