JP4263471B2 - Surface mount type coil components - Google Patents

Description

【００６４】
以上のデータから、外装コア１４を分割して、且つ、突起部を設けたもの（Ｎｏ．２、Ｎｏ３）は、初期インダクタンスを向上させつつも、０．８Ａにおけるインダクタンスを比較的高くすることができ、また、サンプルＮｏ．４よりも０〜０．８Ａにおけるインダクタンスの平坦性が高くすることができる。
【００６５】
また、上述のサンプルＮｏ．３を顕微鏡観察した、この場合、４つの突起部１５ａ，１５ｂ，１６ａ，１６ｂが全てドラム型コア１２に当接しており、コアギャップ１８が一定に保持されていることが判明した。
【００６６】
次に、図３〜図７を参照して、本実施形態の面実装型コイル部品１０の製造方法を説明する。
【００６７】
まず、図３（ａ）に示すようにドラム型コア１２の胴部１２ａにクロスワイズ法によって巻線１１を巻き始める。クロスワイズ法とは、１本の巻線をドラム型コアの下側及び上側にそれぞれ反対周りに巻き付けるものである。尚、同図では、上側の鍔部１２ｂを省略している。図３（ｂ）及び図３（ｃ）は、巻線１１の捲回を終えた状態を示す。
【００６８】
図３（ｂ）に示すように、捲回し終えた後に、巻線１１の両端末１１ａ，１１ｂの先端部の絶縁被覆を除去する。また、図３（ｃ）に示すように、クロスワイズ法では、巻線１１は２段積層された形になり、巻線の幅方向はドラム型コア１２の高さ方向に沿っている。このように積層数を２段に抑えることで、コイル部品１０を低背にすることができる。
【００６９】
次に、図４に示すように、ドラム型コア１２に各部分コア１５，１６を、上述の方法によって接着する。この際、巻線の端末１１ａ，１１ｂがそれぞれのギャップ部２１，２２を通るようにする。
【００７０】
次に、図５に示すように、ワイヤフォーミングによって巻線の端末１１ａ，１１ｂを電極の本体部２５ａ，２６ａ側に近付けた後に、突片２５ｂ，２６ｂをかしめて巻線を仮止めする。この際、上記のようにギャップ部２１，２２は継線するのに十分なスペースとなっているため、作業をスムーズに行える。尚、図４に示す状態から突片２５ｂ，２６ｂをかしめて、突片に押されることで巻線の端末１１ａ，１１ｂが自然と本体部２５ａ，２６ａ側に案内されるようにしてもよい。このように突片２５ｂ，２６ｂを案内片として利用すれば、ワイヤフォーミングの工程を省略することができる。
【００７１】
図６に示すように、次いで、突片２５ｂ，２６ｂに挟まれた巻線の先端部分をカッター等で切断する。
【００７２】
図７に示すように、その後、突片２５ｂ，２６ｂを覆うようにアーク溶接やレーザビーム溶接或いはハンダ付け等を施し、巻線１１と電極２５，２６の継線作業が終了する。以上により、本実施形態の面実装型コイル部品１０が完成する。（第２実施形態）
【００７３】
次に、図８及び図９を参照して、本発明に係る面実装型コイル部品３０の第２実施形態を説明する。図８は、本実施形態のコイル部品の斜視図であり、図９（ａ）は、コイル部品の平面図であり、図９（ｂ）は、図９（ａ）のIXｂ− IXｂ方向の断面図である。
【００７４】
面実装型コイル部品３０は、平角形状の巻線１１がクロスワイズ法で捲回されたドラム型コア１２と、このドラム型コア１２とほぼ一様のコアギャップ１８を介して接着された一対の略Ｕ字型の部分コア３５，３６からなる外装コア３４とを有している。部分コア３５と部分コア３６とは、互いに接合しないように対面位置にギャップ部４１，４２を介してドラム型コア１２を側方から包囲している。
【００７５】
コアギャップ１８は、第１実施形態と同様に、突起部（１３５ａ，１３５ｂ，１３６ａ，１３６ｂ）と接着剤等を使用することで、周方向に渡ってほぼ一定にすることができる。突起部１３５ａ，１３５ｂは部分コア３５から突出しており、突起部１３６ａ，１３６ｂは部分コア３６から突出している。
【００７６】
部分コア３５には、部分コア３６側に向けて平行に突設された直方体形状の脚部（対向突部）３５ａ，３５ｂが形成されており、該脚部３５ａ，３５ｂには、一対のキャップ状電極４５，４６が取付けられている。キャップ状電極４５，４６は、部分コア３５に嵌着される本体部４５ａ，４６ａと、この本体部に連設されてギャップ部４１，４２に位置する突片（案内片）４５ｂ，４６ｂとを備える。
【００７７】
電極本体部４５ａ，４６ａは、各部分コアの脚部３５ａ，３５ｂの外側に位置するの四辺形状の中心部と、その上下四隅に形成された帯状の片を折り曲げてなるフック部４５ｈ，４６ｈとを備える。キャップ状電極４５，４６は、ドラム型コア１２の高さ方向の上側及び下側に形成されたフック部４５ｈ，４６ｈの挟み込みによって、脚部３５ａ，３５ｂに嵌着されている。
【００７８】
このようなキャップ状電極４５，４６を用いることで、部分コアへの電極の取付けが容易で、且つ、不意の脱却を防止することができる。尚、下側のフック部４５ｈ，４６ｈを通じて、プリント配線板との導通が図られる。尚、第１実施形態の面実装型コイル部品において、このようなキャップ状電極を適用することもできる。また、キャップ状電極は、本体部の四辺形領域を部分コアの内側に配置し、各フック部を外側に屈曲させて脚部３５ａ，３５ｂに取付けてもよい。
【００７９】
突片４５ｂ，４６ｂは、第１実施形態と同様に巻線の端末１１ａ，１１ｂを電極本体部との間に挟み込み、固定を補助するためのものである。突片４５ｂは、図中下方に折り曲げて巻線を仮止めするように構成され、これとは反対に、突片４６ｂは、上方に折り曲げて巻線を仮止めするようになっている。
【００８０】
図８は、突片で巻線を抑える前の状態を示し、図９は、突片を折り曲げて巻線を仮止めした状態を示す。図９の状態にアーク溶接やハンダ付け等を施すことにより、継線が完了する。
【００８１】
本実施形態によっても、第１実施形態と同様の効果を得ることができる。すなわち、巻線の端末１１ａ，１１ｂは、部分コア４５，４６間のギャップ部４１，４２において、それぞれキャップ状電極４５，４６と接続される。つまり、巻線１１は外装コア３４の上側を迂回しないため、ほぼ巻線１１の厚さ分（更には溶接或いはハンダ付けの隆起分）は低背化を実現できる。
【００８２】
また、巻線１１とキャップ状電極４５，４６の継線作業に際しては、巻線１１を外装コア３４の肩部で折り曲げる必要は無いため、その作業を容易に行うことができる。しかも、クロスワイズ法を利用して平角巻線１１の幅方向がドラム型コア１２の高さ方向に一致しているため、巻線を捻らずにギャップ部を通すことができ、この観点からも継線作業が極めて容易になっている。
（第３実施形態）
【００８３】
次に、図１０を参照して、本発明に係る面実装型コイル部品の第３実施形態を説明する。
【００８４】
図１０（ａ）は、本実施形態の面実装型コイル部品の平面図であり、図１０（ｂ）は、図１０（ａ）のXｂ− Xｂ方向の断面図である。
【００８５】
本実施形態の面実装型コイル部品５０では、外装コア５４を構成する部分コア５５，５６を同一形状のＵ字型にしている。このため、部分コア５５，５６間に形成されたギャップ部６１とギャップ部６２とを結んだ直線状にドラム型コア１２の軸中心が位置する配置関係になっている。
【００８６】
また、一対の電極６５，６６は、部分コア５５の両脚部に接着剤によって接着されている。電極６５，６６は、部分コア５５に接着される本体部６５ａ，６６ａと、この本体部に連設された突片６５ｂ，６６ｂとからなる。そして、第２実施形態と同様に、平角巻線の端末１１ａ，１１ｂはギャップ部６１，６２に通され、突片６５ｂ，６６ｂによりギャップ部６１，６２において仮止めされている。図１０の状態から、突片６５ｂ，６６ｂ付近を覆うようにアーク溶接やハンダ付け等を施すことで、継線が完了する。
【００８７】
第１実施形態と同様に、突起部（１５５ａ，１５５ｂ，１５６ａ，１５６ｂ）と接着剤等を使用することで、コアギャップ１８を周方向に渡ってほぼ一定にすることができる。突起部１５５ａ，１５５ｂは部分コア５５から突出しており、突起部１５６ａ，１５６ｂは部分コア５６から突出している。
【００８８】
本実施形態においても、上記各実施形態と同様に巻線をギャップ部６１，６２に通すため、ほぼ巻線の厚さ分の低背化を図れる。更に、外装コアの肩部での折り曲げ作業が不要であることから巻線と電極との継線作業を容易に行える。しかも、平角巻線１１の幅方向がドラム型コア１２の高さ方向に一致しているため、巻線を捻らずにギャップ部を通すことができ、この観点からも継線作業が極めて容易になっている。また、本実施形態では、部分コア５５，５６を同一形状にしているため、第２実施形態と比較して、一種の部分コアを作製すれば済むという利点がある。
（第４実施形態）
【００８９】
次に、図１１を参照して、本発明に係る面実装型コイル部品の第４実施形態を説明する。
【００９０】
図１１（ａ）は、本実施形態の面実装型コイル部品の平面図であり、図１１（ｂ）は、図１１（ａ）のXIｂ− XIｂ方向の断面図である。
【００９１】
本実施形態では、面実装型コイル部品を平面視して外装コア５４の外縁に沿って四角形（図１１（ａ）において破線で示す）を仮想した場合に、部分コア５５，５６間のギャップ部６１，６２は対向する２つの頂点付近にそれぞれ位置している。また、部分コア５５，５６におけるギャップ部６１，６２を画成する面は、この仮想四角形の対角線ｌ₁と平行になっている。つまり、ギャップ部６１，６２は、ドラム型コア１２の半径方向に渡って一定の幅になっている。
【００９２】
尚、本例の場合も第１実施形態と同様に、突起部（１５５ａ，１５５ｂ，１５６ａ，１５６ｂ）と接着剤等を使用することで、コアギャップ１８を周方向に渡ってほぼ一定にすることができる。突起部１５５ａ，１５５ｂは部分コア５５から突出しており、突起部１５６ａ，１５６ｂは部分コア５６から突出している。
【００９３】
本実施形態においても、上記各実施形態と同様に平角巻線をギャップ部６１，６２に通すため、ほぼ巻線の厚さ分の低背化を図れる。更に、外装コアの肩部での折り曲げ作業が不要であることから巻線と電極との継線作業を容易に行える。但し、ギャップ部６１，６２が外側に向かって広がる構造としていないため、継線作業の容易性という観点からは、本実施形態よりも第１実施形態の方が優れた構成といえる。
（第５実施形態）
【００９４】
次に、図１２を参照して、本発明に係る面実装型コイル部品の第５実施形態を説明する。
【００９５】
図１２（ａ）は、本実施形態の面実装型コイル部品の平面図であり、図１２（ｂ）は、図１２（ａ）のXIIｂ− XIIｂ方向の断面図である。
【００９６】
本実施形態では、外装コア７４を構成する各部分コア７５，７６は、一方の部分コアから他方の部分コアに向かう方向及びドラム型コア１２の軸の双方に垂直な方向の両端部において、各々の脚部の長さが異なる。すなわち、部分コア７５では脚部７５ｒが他方の脚部７５ｌよりも長く、部分コア７６では脚部７６ｒが他方の脚部７６ｌよりも長くされている。また、部分コア７５と部分コア７６は、同一の形状になっている。
【００９７】
更に、部分コア７５の両脚部７５ｒ，７５ｌには、一対の電極６５，６６が取付けられている。電極６５，６６は第３実施形態と同種の構造をしており、部分コアに接着される本体部６５ａ，６６ａとこれに連設されてギャップ部６１，６２に位置する突片６５ｂ，６６ｂとを備える。
【００９８】
本実施形態においても、上記各実施形態と同様に平角巻線をギャップ部６１，６２に通すため、ほぼ巻線の厚さ分の低背化を図れる。更に、外装コアの肩部での折り曲げ作業が不要であることから巻線と電極との継線作業を容易に行える。
【００９９】
尚、本例の場合も第１実施形態と同様に、突起部（１７５ａ，１７５ｂ，１７６ａ，１７６ｂ）と接着剤等を使用することで、コアギャップ１８を周方向に渡ってほぼ一定にすることができる。突起部１７５ａ，１７５ｂは部分コア７５から突出しており、突起部１７６ａ，１７６ｂは部分コア７６から突出している。
（第６実施形態）
【０１００】
次に、図１３を参照して、本発明に係る面実装型コイル部品の第６実施形態を説明する。
【０１０１】
本実施形態の面実装型コイル部品９０では、ドラム型コア１２を包囲する外装コア８４は、部分コア８５と部分コア８６とで構成されている。そして、部分コア８５と部分コア８６との間には、ギャップ部２１が一箇所だけ形成されている。更に、この一つのギャップ部２１に平角巻線の両端末１１ａ，１１ｂを通し、それぞれ電極２５，２６に接続している。電極としては、例えば第１実施形態のように突片を備えるものを使用できる。
【０１０２】
このような構成にした場合、突片で巻線を挟む仮固定や、その後のアーク溶接やハンダ付け等の継線作業をギャップ部２１の一箇所で集中して行えるため、面実装型コイル部品の製造作業がスムーズになり、生産性の向上にも繋がる。
【０１０３】
尚、本実施形態では、ギャップ部が一つだけ形成されているが、第１実施形態のようにギャップ部が複数形成されている場合に、そのうちの一つに平角巻線の両端末を通すようにしてもよい。
【０１０４】
尚、本例の場合も第１実施形態と同様に、突起部（１８５ａ，１８５ｂ，１８６ａ，１８６ｂ）と接着剤等を使用することで、コアギャップ１８を周方向に渡ってほぼ一定にすることができる。突起部１８５ａ，１８５ｂは部分コア８５から突出しており、突起部１８６ａ，１８６ｂは部分コア８６から突出している。
（第７実施形態）
【０１０５】
次に、図１４を参照して、本発明に係る面実装型コイル部品の第７実施形態を説明する。
【０１０６】
本実施形態の面実装型コイル部品９８では、ドラム型コア１２を包囲する外装コア９４は、部分コア９５、部分コア９６、及び部分コア９７の３つで構成されている。見方を変えると、図１０に示した面実装型コイル部品５０における部分コア５６を二分したものに相当する。このように外装コアを３分割した構造のため、それぞれの部分コア間には、３つのギャップ部９１，９２，９３が形成されている。ギャップ部を複数設ければ、直流重畳特性を良好に、すなわち電流変化に対するインダクタンスの変化が小さくできるという利点がある。
【０１０７】
また、部分コア９５の両脚部には、一対の電極６５，６６が取付けられている。そして、巻線の両端末１１ａ，１１ｂは、ギャップ部９１，９２に通されて、各電極６５，６６に接続されている。
【０１０８】
このように、外装コアを３分割した場合にも、上記各実施形態と同様の効果が得られる。更に、図示は省略するが、外装コアを４つ以上の部分コアで形成する場合にも、同様の効果を得ることができる。
【０１０９】
尚、本例の場合も第１実施形態と同様に、それぞれの部分コア９５，９６，９７に対応して、突起部１９５ａ，１９５ｂ、１９６ａ，１９６ｂ、１９７ａ，１９７ｂを設け、これらの突起部と接着剤等を使用することで、コアギャップ１８を周方向に渡ってほぼ一定にすることができる。突起部１９５ａ，１９５ｂは部分コア９５から突出しており、突起部１９６ａ，１９６ｂは部分コア９６から突出しており、突起部１９７ａ，１９７ｂは部分コア９７から突出している。
尚、第１実施形態における突起部１５ａの形状、形成方法、ドラム型コアとの当接方法、接着・固定方法は、第１実施形態における突起部１５ｂ、突起部１６ａ、突起部１６ｂを始め、第２〜第６実施形態に記載の突起部１３５ａ，１３５ｂ，１３６ａ，１３６ｂ、１５５ａ，１５５ｂ，１５６ａ，１５６ｂ、１７５ａ，１７５ｂ，１７６ａ，１７６ｂ、１８５ａ，１８５ｂ，１８６ａ，１８６ｂ、１９５ａ，１９５ｂ，１９６ａ，１９６ｂ，１９７ａ，１９７ｂと同一である。
【０１１０】
以上、本発明者らによってなされた発明を実施形態に基づき具体的に説明したが、本発明は上記各実施形態に限定されるものではない。例えば、図１０（ｂ）に示す形態（第３実施形態）において、部分コアの脚部を、断面が内側（ドラム型コア側）に向けて高さが窄まるようにテーパ状に形成することができる。この際、電極本体部における上下の片を互いに近付くように屈曲させれば、接着剤を使わずに電極を部分コアに嵌め込むことができる。
【０１１１】
【発明の効果】
以上説明したように、本発明に係る面実装型コイル部品によれば、小型化を達成すると共に製品毎のコイル特性のバラツキを抑制することができる。
【図面の簡単な説明】
【図１】本発明に係る面実装型コイル部品の第１実施形態を示す斜視図である。
【図２】図２（ａ）は、第１実施形態の面実装型コイル部品の平面図であり、図２（ｂ）は、図２（ａ）に示したコイル部品の正面図であり、図２（ｃ）は、図２（ａ）に示したコイル部品の側面図である。
【図３】図３（ａ）は、ドラム型コアに巻線を巻き始める状態を示す図であり、図３（ｂ）及び図３（ｃ）は、巻線の捲回を終えた状態を示す図である。
【図４】面実装型コイル部品の製造の一工程を示し、ドラム型コアと部分コアを接着する状態を示す図である。
【図５】図４に続く工程であり、電極の突片によって巻線を仮止めした状態を示す図である。
【図６】図５に続く工程であり、巻線の先端部を切断した状態を示す図である。
【図７】図６に続く工程であり、電極の突片付近に溶接を施して継線を終えた状態を示す図である。
【図８】本発明に係る面実装型コイル部品の第２実施形態を示す斜視図である。
【図９】図９（ａ）は、第２実施形態の面実装型コイル部品の平面図であり、図９（ｂ）は、図９（ａ）に示したコイル部品のIＸｂ− IＸｂ断面図である。
【図１０】図１０（ａ）は、第３実施形態の面実装型コイル部品の平面図であり、図１０（ｂ）は、図１０（ａ）に示したコイル部品のＸｂ− Ｘｂ断面図である。
【図１１】図１１（ａ）は、第４実施形態の面実装型コイル部品の平面図であり、図１１（ｂ）は、図１１（ａ）に示したコイル部品のＸIｂ− ＸIｂ断面図である。
【図１２】図１２（ａ）は、第５実施形態の面実装型コイル部品の平面図であり、図１２（ｂ）は、図１２（ａ）に示したコイル部品のＸIIｂ− ＸIIｂ断面図である。
【図１３】第６実施形態の面実装型コイル部品の平面図である。
【図１４】第７実施形態の面実装型コイル部品の平面図である。
【図１５】ドラム型コア１２への外装コア１４の取り付け方法を説明するための説明図である。
【図１６】面実装型コイルの直流重畳特性を示すグラフである。
【図１７】従来の面実装型コイル部品を示す平面図と部分拡大図である。
【符号の説明】
１０…面実装型コイル部品、１１…平角巻線、１１ａ，１１ｂ…巻線の端末、１２…ドラム型コア、１２ａ…胴部、１２ｂ，１２ｃ…鍔部、１４…外装コア、１５，１６…部分コア、１８…コアギャップ、２１，２２…ギャップ部、２５，２６…電極、２５ａ，２６ａ…電極の本体部、２５ｂ，２６ｂ…電極の突片、ＳＡ₁…ギャップ部を画成する第１面、ＳＡ₂…ギャップ部を画成する第２面、４５，４６…キャップ状電極、４５ｈ，４６ｈ…フック部、１５ａ，１５ｂ，１６ａ、１６ｂ…突起部。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a surface-mounting coil component that is surface-mounted on a circuit board of an electronic device.
[0002]
[Prior art]
In recent years, electronic devices such as a mobile phone, a hard disk device, and a notebook personal computer have been required to have a small surface mount type coil component. If the parts are downsized, the precision of the parts decreases and it becomes difficult to maintain certain characteristics. Since this characteristic depends on the gap between the drum core and the exterior core, a method of managing the gap with a protrusion has been proposed (for example, see Patent Document 1).
[0003]
FIG. 17A is a plan view of a surface mount type coil component disclosed in the following patent document, and FIG. 17B is an enlarged view of a region B surrounded by a dotted line in FIG.
[0004]
The surface-mounted coil component 100 includes a drum core 101 wound with a winding, and an outer core 102 that surrounds the drum core 101 about its axis. In addition, many manufacturing methods of a magnetic body core are described in various literature (for example, patent document 2).
[0005]
[Patent Document 1]
JP 2002-313635 A
[Patent Document 2]
JP 2000-340444 A
[0006]
[Problems to be solved by the invention]
However, when the drum core 101 is brought into contact with one protrusion 102b of the outer core 102, the other protrusion 102a is not in contact with the drum core 101 as shown in FIG. Problems arise. If the diameter of the inner surface of the outer core 102 is reduced, the protrusion 102a comes into contact with the drum core 101. However, if the diameter is reduced too much, the drum core 101 cannot be inserted into the outer core 102.
[0007]
Therefore, the diameter of the inner surface of the outer core 102 is designed with a margin so that at least one protrusion abuts against the drum core 101. In such a case, the surface-mounting coil component 100 has a margin. In addition to the increase in size, the protrusion 102a still does not come into contact with the drum core 101, so that the coil characteristics for each product cannot be kept constant.
[0008]
The present invention has been made in view of such a problem, and an object of the present invention is to provide a surface mount type coil component that can achieve miniaturization and can suppress variations in coil characteristics of each product.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a surface mount type coil component according to the present invention includes a drum core around which a winding is wound, and a surface mount type including an outer core surrounding the drum core around its axis. The coil component, the drum-type core, is composed of a cylindrical body portion around which a winding is wound, and a pair of disk-shaped flange portions provided at both axial ends of the body portion. The number of protrusions interposed between each of the partial cores and the drum core is plural, and all of these protrusions extend from one of the partial cores and the flanges and come into contact with the other. A core gap is formed between the partial core and the flange portion, and an adhesive is interposed between each partial core and the drum core, and each partial core is in plan view. Around the drum core so that the two tips of each other face each other Are, between each of the tip, the gap portion is formed And one of the opposing surfaces has two protrusions for each of the partial cores. It is characterized by that.
[0010]
For clarity of explanation, a case will be described in which one of the opposing surfaces is the inner surface of the exterior core and the protrusion is provided on the exterior core.
[0011]
In this case, since the outer core is divided, the protrusions of each partial core can be brought into contact with the drum core independently, and therefore, the protrusions are in the gap between the drum core and the outer core. Can be regulated. That is, since it is not necessary to provide the above-mentioned margin, the area of the surface mount type coil component itself is reduced, and a plurality of protrusions inevitably come into contact with the drum core, so that the gap is constant for each component. Thus, it is possible to suppress variations in coil characteristics for each part.
[0012]
The same applies to the case where one of the opposing surfaces is the outer peripheral surface of the drum core and the protrusion is provided on the drum core.
[0013]
That is, since the exterior core is divided, each partial core can independently abut against the protrusion of the drum core, so that the protrusion does not create a gap between the drum core and the exterior core. Can be regulated. That is, since it is not necessary to provide the above-mentioned margin, the area of the surface mount type coil component itself is reduced, and a plurality of protrusions inevitably come into contact with the partial core, so that the gap is constant for each component. Thus, it is possible to suppress variations in coil characteristics for each part.
[0014]
One of the facing surfaces has two protrusions for each of the partial cores, and the angle formed by the line connecting the center of the drum core and the two protrusions is 15 degrees or more and 90 degrees It is characterized by being set to less than. That is, when the drum core is placed on the partial core, the stability of the drum core is poor at the time of manufacture if it is less than 15 degrees or 90 degrees or more. In this surface mount type coil component, the position of the drum core can be stabilized at the time of manufacture. The number of protrusions may be three or more, but here, at least two protrusions are defined.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a surface-mounting coil component and a manufacturing method thereof according to the invention will be described in detail with reference to the accompanying drawings. In addition, the same code | symbol shall be used for the same element and the overlapping description is abbreviate | omitted.
(First embodiment)
[0016]
FIG. 1 is a perspective view showing a surface mount type coil component 10 of the present embodiment, and FIGS. 2A to 2C are a plan view, a front view, and a side view of the coil component 10, respectively. . The surface mount type coil component 10 is surface mounted on a printed wiring board or the like by reflow soldering, and is applied to a power circuit of an electronic device such as a mobile phone, a hard disk device, or a notebook personal computer, for example, 250 kHz to 1 MHz. The switching frequency is preferably used.
[0017]
The surface mount type coil component 10 mainly includes a drum core 12 having a winding 11 wound around a body portion, and an exterior core 14 provided so as to surround the drum core 12 about its axis. Yes. In this example, the winding 11 has a rectangular shape (rectangular section). A round wire type can be used as the winding 11.
[0018]
The exterior core 14 is formed of two partial cores (a first partial core 15 and a second partial core 16) having the same shape, and each of the partial cores 15 and 16 has a core gap 18 between the drum core 12. Is arranged through. A pair of electrodes 25 and 26 are attached to the partial cores 15 and 16, and both ends 11 a and 11 b of the winding 11 are connected to the electrodes 25 and 26, respectively.
[0019]
In order to facilitate understanding of the invention, in FIG. 2A, the electrode 25 side shows a state where the winding and the electrode are connected, and the electrode 26 side is a state before the connection operation is performed. Is shown.
[0020]
The drum-type core 12 is made of, for example, a Ni—Cu—Zn-based magnetic material, a cylindrical body portion 12a around which a winding 11 is wound, and discs provided at both ends of the body portion 12a in the axial direction. It is comprised from the shape of a pair of collar parts 12b and 12c. The axial center of the cylindrical body portion 12a coincides with the axial center of the disk-shaped flange portions 12b and 12c.
[0021]
The winding 11 is made of a copper wire with, for example, a urethane coating for insulation, and the coating is removed at both ends to achieve conduction with the electrodes 25 and 26. In addition, the structure which does not remove a film is also considered. Moreover, in this embodiment, the coil | winding 11 is wound by the trunk | drum 12a by what is called a crosswise method (refer below-mentioned FIG. 3 (a)-FIG.3 (c)).
[0022]
The exterior core 14 can be formed of, for example, a Ni—Cu—Zn based magnetic material, like the drum core 12. Each of the partial cores 15 and 16 has a substantially V-shaped cross section, and its inner wall surface is a concave curved surface corresponding to the outer peripheral surface of the drum core 12 in order to make the core gap 18 constant along the circumferential direction. Is configured.
[0023]
A core gap 18 that is a gap between the drum core 12 and the outer core 14 affects the coil characteristics. The core gap 18 is defined by protrusions 15 a, 15 b, 16 a, and 16 b that protrude from the inner surfaces of the partial cores 15 and 16 that constitute the exterior core 14. Since these protrusions have the same shape, only one protrusion 15a will be described in detail.
[0024]
The protrusion 15 a protrudes from the inner surface of the partial core 15 toward the axial center of the drum core 12. The protrusion 15a of this example extends linearly on the inner surface of the partial core 15 along the axial direction of the drum core 12, and the cross section perpendicular to the axial direction forms a triangle, a truncated cone, or a semicircle. ing. The tip of the protrusion 15 a on the drum core 12 side is in contact with the flanges 12 b and 12 c of the drum core 12. The contact of the protrusion 15a with the flanges 12b and 12c is a line contact.
[0025]
Two projecting portions 15a and 15b are located along the circumferential direction of the partial core 15, and the opening angle θ between them is set as follows. That is, when the mutually facing surfaces of the partial core 15 and the drum core 12 are the respective facing surfaces, one of these facing surfaces, in this example, the facing surface on the partial core 15 side is 2 to one partial core 15. Two protrusions 15a and 15b are provided.
[0026]
The angle θ1 (θ2) formed by the line connecting the center of the drum core 12 and the two protrusions 15a and 15b is set to 15 degrees or more and less than 90 degrees. This is because when the drum-type core is placed on the partial core, the stability of the drum-type core is poor at the time of manufacture if it is less than 15 degrees or 90 degrees or more. In this surface mount type coil component, the position of the drum core can be stabilized during the manufacturing shown in FIG. The number of protrusions may be three or more, but here, at least two protrusions are defined.
[0027]
It should be noted that θ1 (θ2) is not less than 90 degrees as necessary.
[0028]
Further, the relationship between the partial core 16 and the two protrusions 16 a and 16 b and the drum core 12 is the same as the relationship between the partial core 15 and the two protrusions 15 a and 15 b and the drum core 12.
[0029]
As can be seen from FIGS. 2B and 2C, the height of the partial cores 15 and 16 is slightly lower than that of the drum core 12. Further, the partial cores 15 and 16 are arranged around the drum core 12 so that the two tip portions thereof face each other in plan view, and gap portions 21 and 22 (see FIG. 2 (a) is a region indicated by a broken line).
[0030]
The partial cores 15 and 16 are not formed by simply dividing the outer core having a rectangular outer shape in a plan view along the diagonal line, but are formed in a shape in which respective tip portions facing the other partial core are cut out or chamfered. Sintered and formed. And the surface (first surface) SA of the partial core 15 ₁ And the surface (second surface) SB of the partial core 16 ₁ And the gap portion 21 is defined, and the surface (first surface) SA of the partial core 15 ₂ And the surface (second surface) SB of the partial core 16 ₂ A gap portion 22 is defined.
[0031]
More specifically, the surface SA that defines the gap portion 21 in the partial core 15. ₁ And a surface SB that defines the gap portion 21 in the partial core 16 adjacent to the partial core 15. ₁ Is formed such that the distance between them increases as the distance from the center of the drum core 12 increases. Surface SA is also on the gap 22 side. ₂ And face SB ₂ Similarly, it is formed so as to spread outward.
[0032]
That is, each gap part 21 and 22 becomes the space which spreads as it goes outside. In the present embodiment, the surface SA ₁ And face SB ₁ Is in a substantially vertical positional relationship, and similarly the surface SA ₂ And face SB ₂ Are also in a substantially vertical positional relationship. Here, the term “substantially perpendicular” means that the angle between both surfaces does not necessarily need to be 90 °, and there may be a slight deviation. As a range of deviation, for example, 80 ° to 100 ° can be considered.
[0033]
The electrodes 25, 26 include main body portions 25 a, 26 a attached in the vicinity of the gap portions 21, 22 in the partial cores 15, 16, and belt-shaped projecting pieces (continuous to the main body portions and positioned in the gap portions 21, 22). Guide pieces) 25b and 26b. The main body portions 25a and 26a have a rectangular central portion that is in surface contact with the outer wall of the partial core, and an extending portion that extends from the central portion along the X direction, as shown in FIG. Thus, the Z-direction length of the extended portion is shorter than the Z-direction length of the center portion.
[0034]
And the said extension part of the main-body parts 25a and 26a is surface SA. ₁ , Surface SB ₂ The protrusions 25b and 26b protrude outward from the bent portion. Further, the lower ends (bottom portions) of the electrodes 25 and 26 in the −Z direction are bent toward the drum-side core 12, and the bottom portions are housed in step portions formed on the bottom surface of the partial core. The electrodes 25 and 26 are bonded to the partial core with various adhesives such as a one-component epoxy resin. By performing reflow soldering or the like on the bottom of such an electrode, the surface mount type coil component 10 is mounted on the printed wiring board.
[0035]
The electrodes 25 and 26 are made of phosphor bronze, for example, and are plated except for a region facing the partial core. The plating process can be performed by, for example, applying a base plating with Ni having a thickness of 0.5 μm and then plating with 100% Sn having a thickness of 4 μm.
[0036]
Further, the projecting pieces 25b and 26b of the electrodes 25 and 26 are formed on the surface SA of the partial core 15 as shown by a two-dot chain line in FIG. ₁ It is extended | stretched in the substantially normal line direction (X direction). This state can also be seen from FIG. When connecting, the ends 11a and 11b of the winding are passed through the gap portions 21 and 22, respectively, and the projecting pieces 25b and 26b are bent toward the main body portions 25a and 26a of the electrode by caulking or the like. The part from which the coating | coated of the terminal 11a, 11b of a coil | winding was removed is inserted | pinched between. In addition, the structure which does not remove a film is also considered.
[0037]
It is to be noted that the pinching by the projecting piece is temporarily fixed, and the connecting operation is completed by performing arc welding, laser beam welding, soldering, or the like from above as in the gap portion 21 side of FIG. By adopting a method of temporarily fixing with the projecting pieces 25b and 26b in this way, it is possible to easily and reliably perform subsequent operations such as soldering. Furthermore, when mounting the surface mount type coil component 10 on a printed wiring board or the like, even if the welded portion or solder applied to the connecting portion is melted by heat such as soldering, the winding is suppressed by the protruding piece. Therefore, it is possible to prevent disconnection from being separated from the electrodes 25 and 26.
[0038]
Next, effects obtained from the surface mount type coil component will be described. As described above, the winding terminals 11a and 11b are connected to the electrodes 25 and 26 in the gap portions 21 and 22 between the partial cores 15 and 16, respectively. That is, since the winding 11 does not bypass the upper side of the outer core 14, there is no problem that the height of the coil component is increased as much as the winding 11 is placed on the outer core 14. Furthermore, the height of the welded or soldered bump) can be reduced. Further, when connecting the winding 11 and the electrodes 25 and 26, it is not necessary to bend the winding 11 at the shoulder portion of the outer core 14, so that the operation can be easily performed.
[0039]
Further, the surface SA of the partial core 15 ₁ And the surface SB of the partial core 16 ₁ Is substantially vertical, and is formed so that the distance between each other gradually increases outward, so that the gap portion 21 is a sufficient space for performing the connecting work. The same can be said for the gap portion 22.
[0040]
In this embodiment, the gaps 21 and 22 are connected. However, the connection may be performed by drawing the winding terminals 11a and 11b from the gaps 21 and 22. That is, it is only necessary that the end of the winding is connected to the electrode after passing through the gap portions 21 and 22. This form will be described in detail. For example, the winding drawn from the gap portion is a surface SA. ₁ The outer side of the outer core 14 is bent and connected to the electrode in the outer peripheral region.
[0041]
Also in this case, it is not necessary to bend the winding 11 at the shoulder portion of the outer core 14, so that the connecting work can be easily performed. However, if the outer peripheral portion of the outer core 14 is connected, the dimensions of the coil component 10 are increased by the protruding portion of the electrode required for the connection and the bulge of the welding. Therefore, from the viewpoint of miniaturization, the gap portions 21 and 22 It is preferable to connect the winding and the electrode.
[0042]
Furthermore, in this embodiment, as shown in FIG. 2B and FIG. 2C, the ends 11a and 11b of the windings are not bent in the height direction (Z direction) of the drum-type core 12 and are gap portions. 21 and 22. That is, when the surface-mounted coil component 10 is viewed from the side, the winding terminals 11a and 11b are linear. With such a configuration, the wiring pattern of the windings in the coil component 10 is very simple compared to the case where the line segment from the winding body 12a toward the outer core 14 is bent. Line work can also be easily performed.
[0043]
Moreover, since the winding 11 is wound around the drum core 12 by the crosswise method as described later, the width direction thereof coincides with the height direction of the drum core 12 (FIG. 3C). reference). And since the gap parts 21 and 22 are also extended in the height direction of the drum core 12, the gap part can be passed without twisting the coil | winding 11, and the connection work is also easy from this viewpoint. It can be said.
[0044]
Further, as shown in FIG. 1, the protruding piece 25 b of the electrode 25 attached to the partial core 15 is an adjacent portion when extended in a direction (X direction) orthogonal to the height direction of the drum core 12. The core 16 is not contacted. Thereby, since the partial core 16 does not hinder the extension of the protruding piece 25b in the X direction, a sufficient interval between the electrode main body portion 25a and the tip end portion of the protruding piece 25b can be secured, and the winding can be connected to the electrode. It becomes easy to pass between the main-body part 25a and the protrusion 25b, and a connecting operation becomes easy.
[0045]
Here, with reference to FIG.2 (c), it demonstrates in full detail about the protrusions 25b and 26b of the electrodes 25 and 26. FIG. As shown in the figure, the base portion 26c of the electrode protrusion 26b, that is, the vicinity of the boundary with the main body portion 26a, is located around the flange portion 12c in the height direction (Z direction) of the drum core. (In the figure, the hidden portion of the collar portion 12c is indicated by a broken line).
[0046]
In this way, by positioning the base portion 26c of the protruding piece around the flange portion 12c, not around the trunk portion 12a, the presence of the protruding piece 26b is obstructed when the terminal 11b of the winding 11 is passed through the gap portion 22. The connection work can be performed smoothly. As shown in FIG. 2B, the base portion of the projecting piece 25b is located not around the trunk portion 12a but around the collar portion 12c.
[0047]
Moreover, the X direction length of the protrusions 25b and 26b is more than the space | interval of the collar part 12b and the collar part 12c. For this reason, even if both ends 11a and 11b of the winding are pulled out from any height position of the trunk portion 12a, it can be suppressed by the projecting pieces 25b and 26b. In this embodiment, the windings are wound by the crosswise method, and the windings are stacked in two stages in the body portion 12a, and one end 11a of the winding is pulled out from the upper side as shown in FIG. 2 (b). As shown in FIG. 2 (c), the other end 11b of the winding is drawn from the lower side. Even when the height positions of the drawn-out windings are different on both ends, the terminals 11a and 11b can be suppressed by setting the length X of the projecting piece as described above.
[0048]
Accordingly, it is not necessary to prepare electrodes for each of the terminals 11a and 11b, and only one type of electrode can be used, so that production efficiency can be increased and costs can be reduced. In addition, as another method for sharing the ends of the windings with one kind of electrode in this way, projecting pieces are provided on both the upper and lower sides of the electrode, and the total length of each projecting piece is set between the flanges 12b and 12c It is mentioned to make more than the length of.
[0049]
As described above, the surface-mounted coil component described above includes the drum core 12 wound with the winding and the outer core 14 surrounding the drum core 12 about its axis. Here, one of the opposing surfaces of both the drum core 12 and the outer core 14 has a plurality of protrusions 15a, 15b, 16a, 16b, and the outer core 14 includes the protrusions 15a, 15b, 16a, 16b is divided into a plurality of partial cores so as to contact the other of the opposing surfaces. The core gap 18 is constant along the circumferential direction of the drum core 12, and the core gap 18 is filled with an adhesive.
[0050]
In the above description, one of the opposing surfaces referred to here is the inner surface of the exterior core 14, and the protrusions 15 a, 15 b, 16 a, and 16 b are provided on the exterior core 14. Since the outer core 14 is divided, the projections 15 a, 15 b, 16 a, 16 b of the partial cores 15, 16 abut against the drum core 12 independently.
[0051]
The protrusions 15a, 15b, 16a, and 16b define the gap between the drum core 12 and the outer core 14 and the core gap 18, but by dividing the core, there is a margin of the outer core diameter for inserting the drum core. Is eliminated, and the surface-mounted coil component itself can be made smaller.
[0052]
Further, since the plurality of protrusions 15a, 15b, 16a, 16b inevitably come into contact with the drum-type core 12 due to the division, the gap as the core gap 18 becomes constant for each part, and variation in coil characteristics for each part is caused. It becomes possible to suppress.
[0053]
The same applies to the case where one of the opposing surfaces is the outer peripheral surface of the drum core 12 and the protrusions 15a, 15b, 16a, 16b are provided on the drum core 12 (not shown). That is, since the outer core 14 is divided, each of the partial cores 15 and 16 can be brought into contact with the protrusions of the drum core independently, so that the protrusions correspond to the drum core 12 and the outer core 14. It is possible to regulate the gap between the two. Also in this case, the area of the surface mount type coil component itself is reduced, and a plurality of protrusions inevitably abut the partial core, so that the gap as the core gap 18 is constant for each component, and the coil for each component It becomes possible to suppress variation in characteristics.
[0054]
The protrusions 15a, 15b, 16a, and 16b described above are made of the same material as the outer core 14, that is, a magnetic material. In other words, the protrusions 15a, 15b, 16a, 16b are formed when the outer core 14 is sintered.
[0055]
FIG. 15 is an explanatory diagram for explaining a method of attaching the outer core 14 to the drum core 12. As described above, the exterior core 14 includes the partial core 15 and the partial core 16. It is assumed that a winding is wound around the drum core 12 in advance.
First, the drum-type core 12 and the partial cores 15 and 16 having protrusions are formed by sintering. These raw materials are magnetic materials made of Ni—Cu—Zn-based ferrite powder, and the temperature during sintering is about 800 ° C. to 1000 ° C.
Next, after the partial core 15 is placed on the magnet G, when the drum core 12 is placed on the magnet G, the drum core 12 is sucked onto the partial core 15 by the attractive force B due to the magnetic field of the magnet G. In this state, the drum core 12 is fixed to the partial core 15. In the fixing, an adhesive R15 is used. This adhesive can be applied on the partial core 15 in advance (see FIG. 15A).
[0056]
Thereafter, the surface mount type coil component intermediate body composed of the drum core 12 and the partial core 15 that have been bonded is inverted and placed on the magnet G. The attachment method of the partial core 16 to the drum core 12 is the same as the attachment method of the partial core 15, and the adhesive R16 is used as an adhesive necessary for the attachment. It shall be read as the partial core 16 (FIG. 15B).
[0057]
As described above, in this method of manufacturing a surface-mounted coil component, the drum-type core 12 around which the winding is wound and the outer core 14 surrounding the drum-type core 12 about its axis are provided. The core 14 is directed to a method for manufacturing a surface-mounted coil component having the first and second partial cores 15 and 16, and includes the following steps.
(1) A first partial core 15 having a concave surface provided with projections 15a and 15b and a second partial core 16 having a concave surface provided with projections 16a and 16b are prepared.
{Circle around (2)} The concave projections 15 a and 15 b of the first partial core 15 are brought into contact with the outer peripheral surface of the drum core 12.
(3) The concave projections 16 a and 16 b of the second partial core 16 are brought into contact with the outer peripheral surface of the drum core 12.
[0058]
Since the exterior core 14 is composed of the first partial core 15 and the second partial core 16 having the protrusions on the concave surface, the protrusions 15a, 15b, 16a, 16b are the outer peripheral surfaces of the drum core 12 in the contact step. , It securely abuts against the flanges 12b, 12c. Therefore, the variation in the gap between the drum core 12 and the outer core 14 defined by the protrusions 15a, 15b, 16a, and 16b can be suppressed, and the characteristics of each product can be made constant.
[0059]
In the above-mentioned steps (2) and (3), the partial core 15 (16) and the drum core 12 are arranged close to each other in a state where the drum core 12 and the partial core 15 (16) are disposed in the magnetic field. ing. That is, when the drum core 12 and the partial core 15 (16) are arranged in a magnetic field, since these cores are made of a magnetic material, an attractive force acts between them. Therefore, the partial core 15 (16) and the drum-type core 12 are attracted, and the concave protrusions 15a and 15b (16a and 16b) of the partial core 15 (16) are surely brought into contact with the outer peripheral surface of the drum-type core 12. Become. In addition to the magnetic field, a manufacturing method using vacuum adsorption is also conceivable.
Note that the protrusions 15a, 15b, 16a, and 16b can be formed of a nonmagnetic material. In this case, since the protrusion itself does not affect the coil characteristics, it is possible to further suppress variations in the coil characteristics for each part. When the protrusions 15a, 15b, 16a, and 16b are made of glass or carbon, for example, they may be made of fiber.
[0060]
The protrusions 15a, 15b, 16a, and 16b may be formed on the drum core 12 in the same manner, whether they are the same material as the outer core 14, or different materials, glass, or fibers. Can do.
[0061]
When there is a protrusion on the drum core 12 side, the surface mounting type coil component manufacturing method includes: (1) a step of preparing first and second partial cores 15 and 16 having concave surfaces, and (2) a first part. A step of bringing the concave surface of the core 15 into contact with the protrusion provided on the outer peripheral surface of the drum-type core 12; and (3) the concave surface of the second partial core 16 on the protrusion provided on the outer peripheral surface of the drum-type core 12. And a step of abutting.
[0062]
Even in such a case, since the protrusion is provided on the outer peripheral surface of the drum core 12 and the outer core 14 is divided, the protrusion of the drum core 12 reliably contacts at least the first partial core 15. Therefore, variation in the gap between the drum core and the outer core defined by the protrusion can be suppressed, and the characteristics of each product can be made constant.
[0063]
FIG. 16 is a graph showing the DC superposition characteristics of the surface mount coil described above. The horizontal axis represents current Idc (A), and the vertical axis represents inductance Ls (μH). The dimensions of the outer core are 4.7 mm square, the height is 1.8 mm, the inner diameter is 3.6 mm, the height of the protrusion is 0.05 mm, and the sample No. The number of turns other than 3 is 16.5.
[Table 1]

[0064]
From the above data, those with the outer core 14 divided and provided with the protrusions (No. 2 and No. 3) can increase the inductance at 0.8 A relatively high while improving the initial inductance. Sample No. The flatness of the inductance at 0 to 0.8 A can be made higher than 4.
[0065]
In addition, the above sample No. In this case, it was found that the four protrusions 15a, 15b, 16a, and 16b are all in contact with the drum core 12, and the core gap 18 is held constant.
[0066]
Next, with reference to FIGS. 3-7, the manufacturing method of the surface mount type coil component 10 of this embodiment is demonstrated.
[0067]
First, as shown in FIG. 3A, the winding 11 is started to be wound around the body portion 12a of the drum core 12 by the crosswise method. In the crosswise method, one winding is wound around the lower side and the upper side of the drum core in opposite directions. In the figure, the upper flange 12b is omitted. FIG. 3B and FIG. 3C show a state in which the winding 11 has been wound.
[0068]
As shown in FIG. 3 (b), after the winding is completed, the insulating coating on the tip portions of both ends 11a, 11b of the winding 11 is removed. Further, as shown in FIG. 3C, in the crosswise method, the windings 11 are stacked in two stages, and the width direction of the windings is along the height direction of the drum core 12. Thus, the coil component 10 can be made low-profile by suppressing the number of layers to two.
[0069]
Next, as shown in FIG. 4, the partial cores 15 and 16 are bonded to the drum core 12 by the above-described method. At this time, the winding terminals 11a and 11b pass through the gap portions 21 and 22, respectively.
[0070]
Next, as shown in FIG. 5, after the ends 11a and 11b of the winding are brought closer to the electrode body portions 25a and 26a side by wire forming, the protruding pieces 25b and 26b are caulked to temporarily fix the winding. At this time, as described above, the gap portions 21 and 22 have a sufficient space for connection, so that the operation can be performed smoothly. In addition, the protrusions 25b and 26b may be caulked from the state shown in FIG. 4, and the winding terminals 11a and 11b may be naturally guided to the main body portions 25a and 26a by being pushed by the protrusions. Thus, if the protruding pieces 25b and 26b are used as guide pieces, the wire forming step can be omitted.
[0071]
Next, as shown in FIG. 6, the tip portion of the winding sandwiched between the projecting pieces 25b and 26b is cut with a cutter or the like.
[0072]
As shown in FIG. 7, after that, arc welding, laser beam welding, soldering, or the like is performed so as to cover the projecting pieces 25b, 26b, and the connecting work of the winding 11 and the electrodes 25, 26 is completed. Thus, the surface mount type coil component 10 of the present embodiment is completed. (Second Embodiment)
[0073]
Next, with reference to FIG.8 and FIG.9, 2nd Embodiment of the surface mount-type coil component 30 which concerns on this invention is described. FIG. 8 is a perspective view of the coil component of the present embodiment, FIG. 9A is a plan view of the coil component, and FIG. 9B is a cross-section in the IXb-IXb direction of FIG. 9A. FIG.
[0074]
The surface-mounted coil component 30 includes a drum core 12 in which a rectangular winding 11 is wound by a crosswise method, and a pair of drum cores 12 bonded to each other via a substantially uniform core gap 18. And an exterior core 34 composed of substantially U-shaped partial cores 35 and 36. The partial core 35 and the partial core 36 surround the drum core 12 from the side via gap portions 41 and 42 at facing positions so as not to be joined to each other.
[0075]
Similarly to the first embodiment, the core gap 18 can be made substantially constant in the circumferential direction by using a protrusion (135a, 135b, 136a, 136b) and an adhesive. The protrusions 135 a and 135 b protrude from the partial core 35, and the protrusions 136 a and 136 b protrude from the partial core 36.
[0076]
The partial core 35 is formed with rectangular parallelepiped legs (opposing protrusions) 35a and 35b projecting in parallel toward the partial core 36, and a pair of caps is provided on the legs 35a and 35b. The electrode 45,46 is attached. The cap-shaped electrodes 45 and 46 include main body portions 45a and 46a that are fitted to the partial core 35, and projecting pieces (guide pieces) 45b and 46b that are connected to the main body portion and are positioned in the gap portions 41 and 42, respectively. Prepare.
[0077]
The electrode main body portions 45a and 46a are formed in quadrilateral central portions located outside the leg portions 35a and 35b of the partial cores, and hook portions 45h and 46h formed by bending strip-like pieces formed at the upper and lower four corners, respectively. Is provided. The cap-shaped electrodes 45 and 46 are fitted to the leg portions 35a and 35b by sandwiching hook portions 45h and 46h formed on the upper and lower sides of the drum core 12 in the height direction.
[0078]
By using such cap-shaped electrodes 45 and 46, it is easy to attach the electrode to the partial core, and it is possible to prevent unexpected escape. In addition, electrical connection with the printed wiring board is achieved through the lower hooks 45h and 46h. In addition, such a cap-shaped electrode can also be applied to the surface mount type coil component of the first embodiment. The cap-shaped electrode may be attached to the leg portions 35a and 35b by arranging the quadrangular region of the main body portion inside the partial core and bending each hook portion outward.
[0079]
Similar to the first embodiment, the projecting pieces 45b and 46b sandwich the winding terminals 11a and 11b between the electrode main body portions and assist fixing. The protruding piece 45b is configured to be bent downward in the drawing to temporarily fix the winding, and on the contrary, the protruding piece 46b is bent upward to temporarily fix the winding.
[0080]
FIG. 8 shows a state before the winding is suppressed by the protruding piece, and FIG. 9 shows a state where the protruding piece is bent and the winding is temporarily fixed. The connection is completed by performing arc welding, soldering, or the like in the state of FIG.
[0081]
Also according to this embodiment, the same effect as that of the first embodiment can be obtained. That is, the winding terminals 11a and 11b are connected to the cap-shaped electrodes 45 and 46 at the gap portions 41 and 42 between the partial cores 45 and 46, respectively. That is, since the winding 11 does not circumvent the upper side of the outer core 34, the thickness of the winding 11 (and the bulging portion by welding or soldering) can be reduced.
[0082]
Further, when connecting the winding 11 and the cap-shaped electrodes 45 and 46, it is not necessary to bend the winding 11 at the shoulder of the outer core 34, so that the operation can be easily performed. Moreover, since the width direction of the flat winding 11 matches the height direction of the drum core 12 using the crosswise method, the gap can be passed without twisting the winding. Connecting work is extremely easy.
(Third embodiment)
[0083]
Next, a third embodiment of the surface mount type coil component according to the present invention will be described with reference to FIG.
[0084]
FIG. 10A is a plan view of the surface mount type coil component of the present embodiment, and FIG. 10B is a cross-sectional view in the Xb-Xb direction of FIG.
[0085]
In the surface mount type coil component 50 of the present embodiment, the partial cores 55 and 56 constituting the exterior core 54 are U-shaped with the same shape. For this reason, the axial relationship of the drum core 12 is arranged in a straight line connecting the gap portion 61 and the gap portion 62 formed between the partial cores 55 and 56.
[0086]
The pair of electrodes 65 and 66 are bonded to both leg portions of the partial core 55 with an adhesive. The electrodes 65 and 66 include main body portions 65a and 66a that are bonded to the partial core 55, and projecting pieces 65b and 66b that are connected to the main body portion. Similarly to the second embodiment, the ends 11a and 11b of the rectangular winding are passed through the gap portions 61 and 62 and temporarily fixed at the gap portions 61 and 62 by the projecting pieces 65b and 66b. From the state of FIG. 10, arc welding, soldering, or the like is performed so as to cover the vicinity of the protruding pieces 65 b and 66 b, thereby completing the connection.
[0087]
Similar to the first embodiment, the core gap 18 can be made substantially constant in the circumferential direction by using the protrusions (155a, 155b, 156a, 156b) and an adhesive. The protrusions 155 a and 155 b protrude from the partial core 55, and the protrusions 156 a and 156 b protrude from the partial core 56.
[0088]
Also in the present embodiment, since the winding is passed through the gap portions 61 and 62 as in the above embodiments, the height can be reduced by the thickness of the winding. Further, since the bending work at the shoulder portion of the exterior core is unnecessary, the wire connecting work between the winding and the electrode can be easily performed. In addition, since the width direction of the flat winding 11 coincides with the height direction of the drum core 12, the gap portion can be passed without twisting the winding. From this point of view, the connecting work is very easy. It has become. Moreover, in this embodiment, since the partial cores 55 and 56 are made into the same shape, compared with 2nd Embodiment, there exists an advantage that a kind of partial core should just be produced.
(Fourth embodiment)
[0089]
Next, with reference to FIG. 11, 4th Embodiment of the surface mount-type coil component which concerns on this invention is described.
[0090]
Fig.11 (a) is a top view of the surface mount type coil component of this embodiment, FIG.11 (b) is sectional drawing of the XIb-XIb direction of Fig.11 (a).
[0091]
In the present embodiment, when a surface mount type coil component is viewed in plan and a quadrangle (shown by a broken line in FIG. 11A) is assumed along the outer edge of the outer core 54, a gap portion between the partial cores 55 and 56 is assumed. 61 and 62 are located in the vicinity of two opposite vertices, respectively. Further, the surfaces defining the gap portions 61 and 62 in the partial cores 55 and 56 are diagonal lines l of the virtual rectangle. ₁ It is parallel to. That is, the gap portions 61 and 62 have a constant width across the radial direction of the drum core 12.
[0092]
In the case of this example, similarly to the first embodiment, the core gap 18 is made substantially constant in the circumferential direction by using the protrusions (155a, 155b, 156a, 156b) and an adhesive. Can do. The protrusions 155 a and 155 b protrude from the partial core 55, and the protrusions 156 a and 156 b protrude from the partial core 56.
[0093]
Also in this embodiment, since the rectangular winding is passed through the gap portions 61 and 62 as in the above-described embodiments, the height of the winding can be reduced substantially. Further, since the bending work at the shoulder portion of the exterior core is unnecessary, the wire connecting work between the winding and the electrode can be easily performed. However, since the gap portions 61 and 62 are not structured to expand outward, the first embodiment can be said to be superior to the present embodiment from the viewpoint of easy connection work.
(Fifth embodiment)
[0094]
Next, with reference to FIG. 12, 5th Embodiment of the surface mount-type coil component which concerns on this invention is described.
[0095]
Fig.12 (a) is a top view of the surface mount type coil component of this embodiment, FIG.12 (b) is sectional drawing of the XIIb-XIIb direction of Fig.12 (a).
[0096]
In the present embodiment, each of the partial cores 75 and 76 constituting the exterior core 74 is respectively provided at both ends in a direction from one partial core toward the other partial core and in a direction perpendicular to both the axes of the drum core 12. The leg length is different. That is, in the partial core 75, the leg 75r is longer than the other leg 75l, and in the partial core 76, the leg 76r is longer than the other leg 76l. Further, the partial core 75 and the partial core 76 have the same shape.
[0097]
Further, a pair of electrodes 65 and 66 are attached to both leg portions 75 r and 75 l of the partial core 75. The electrodes 65 and 66 have the same type of structure as that of the third embodiment, and main body portions 65a and 66a bonded to the partial core, and projecting pieces 65b and 66b connected to the main portions 65a and 66b and positioned in the gap portions 61 and 62, Is provided.
[0098]
Also in this embodiment, since the rectangular winding is passed through the gap portions 61 and 62 as in the above-described embodiments, the height of the winding can be reduced substantially. Further, since the bending work at the shoulder portion of the exterior core is unnecessary, the wire connecting work between the winding and the electrode can be easily performed.
[0099]
In the case of this example, similarly to the first embodiment, the core gap 18 is made substantially constant in the circumferential direction by using the protrusions (175a, 175b, 176a, 176b) and an adhesive. Can do. The protrusions 175a and 175b protrude from the partial core 75, and the protrusions 176a and 176b protrude from the partial core 76.
(Sixth embodiment)
[0100]
Next, with reference to FIG. 13, 6th Embodiment of the surface mount-type coil component which concerns on this invention is described.
[0101]
In the surface-mounted coil component 90 of the present embodiment, the exterior core 84 that surrounds the drum core 12 includes a partial core 85 and a partial core 86. In addition, only one gap portion 21 is formed between the partial core 85 and the partial core 86. Further, both ends 11a and 11b of the rectangular winding are passed through this one gap portion 21, and are connected to the electrodes 25 and 26, respectively. As an electrode, what is provided with a protrusion piece like 1st Embodiment, for example can be used.
[0102]
In such a configuration, the surface fixing type coil component can be performed by concentrating at one location of the gap portion 21 such as temporary fixing with the projecting pieces sandwiched between the windings, and the subsequent arc welding or soldering. The manufacturing process becomes smoother, leading to improved productivity.
[0103]
In the present embodiment, only one gap portion is formed. However, when a plurality of gap portions are formed as in the first embodiment, both ends of the rectangular winding are passed through one of them. You may do it.
[0104]
In the case of this example, similarly to the first embodiment, the core gap 18 is made substantially constant in the circumferential direction by using the protrusions (185a, 185b, 186a, 186b) and an adhesive. Can do. The protrusions 185 a and 185 b protrude from the partial core 85, and the protrusions 186 a and 186 b protrude from the partial core 86.
(Seventh embodiment)
[0105]
Next, a seventh embodiment of the surface mount type coil component according to the present invention will be described with reference to FIG.
[0106]
In the surface mount type coil component 98 of the present embodiment, the outer core 94 that surrounds the drum core 12 is composed of a partial core 95, a partial core 96, and a partial core 97. In other words, the partial core 56 in the surface mount type coil component 50 shown in FIG. Since the outer core is thus divided into three parts, three gap portions 91, 92, 93 are formed between the respective partial cores. Providing a plurality of gap portions has an advantage that the DC superposition characteristics can be improved, that is, the change in inductance with respect to the current change can be reduced.
[0107]
A pair of electrodes 65 and 66 are attached to both legs of the partial core 95. Then, both ends 11a and 11b of the winding are passed through the gap portions 91 and 92 and connected to the electrodes 65 and 66, respectively.
[0108]
Thus, even when the exterior core is divided into three, the same effects as those of the above embodiments can be obtained. Furthermore, although illustration is omitted, the same effect can be obtained when the exterior core is formed of four or more partial cores.
[0109]
In the case of this example, similarly to the first embodiment, projections 195a, 195b, 196a, 196b, 197a, 197b are provided corresponding to the respective partial cores 95, 96, 97. By using an adhesive or the like, the core gap 18 can be made substantially constant over the circumferential direction. The protrusions 195a and 195b protrude from the partial core 95, the protrusions 196a and 196b protrude from the partial core 96, and the protrusions 197a and 197b protrude from the partial core 97.
In addition, the shape of the protrusion part 15a in 1st Embodiment, the formation method, the contact method with a drum-type core, and the adhesion / fixation method are the protrusion part 15b, protrusion part 16a, protrusion part 16b in 1st Embodiment, Projections 135a, 135b, 136a, 136b, 155a, 155b, 156a, 156b, 175a, 175b, 176a, 176b, 185a, 185b, 186a, 186b, 195a, 195b, 196a, described in the second to sixth embodiments The same as 196b, 197a, 197b.
[0110]
As mentioned above, although the invention made by the present inventors has been specifically described based on the embodiments, the present invention is not limited to the above embodiments. For example, in the embodiment shown in FIG. 10B (third embodiment), the leg portion of the partial core is formed in a tapered shape so that the height is narrowed toward the inside (drum-type core side). Can do. At this time, if the upper and lower pieces of the electrode main body are bent so as to approach each other, the electrode can be fitted into the partial core without using an adhesive.
[0111]
【The invention's effect】
As described above, according to the surface mount type coil component according to the present invention, it is possible to achieve miniaturization and to suppress variations in coil characteristics among products.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a first embodiment of a surface-mounted coil component according to the present invention.
FIG. 2A is a plan view of the surface mount type coil component according to the first embodiment, and FIG. 2B is a front view of the coil component shown in FIG. FIG. 2C is a side view of the coil component shown in FIG.
FIG. 3 (a) is a diagram showing a state where winding is started around a drum core, and FIGS. 3 (b) and 3 (c) are diagrams showing a state where winding of the winding is finished. FIG.
FIG. 4 is a diagram showing a process of manufacturing a surface mount type coil component and showing a state in which a drum core and a partial core are bonded together.
FIG. 5 is a diagram illustrating a state in which a winding is temporarily fixed by a protruding piece of an electrode, following the step of FIG. 4;
6 is a view subsequent to FIG. 5, showing a state in which the tip of the winding is cut. FIG.
FIG. 7 is a diagram illustrating a state in which welding is performed in the vicinity of the protruding piece of the electrode and the connection is completed after the step shown in FIG. 6;
FIG. 8 is a perspective view showing a second embodiment of the surface-mounted coil component according to the present invention.
9A is a plan view of the surface mount type coil component of the second embodiment, and FIG. 9B is a cross-sectional view of the coil component shown in FIG. 9A taken along the line IXb-IXb. It is.
FIG. 10A is a plan view of the surface mount type coil component of the third embodiment, and FIG. 10B is a cross-sectional view of the coil component shown in FIG. 10A taken along line Xb-Xb. It is.
FIG. 11A is a plan view of a surface mount type coil component according to a fourth embodiment, and FIG. 11B is a cross-sectional view taken along line XIb-XIb of the coil component shown in FIG. It is.
12A is a plan view of a surface mount type coil component according to a fifth embodiment, and FIG. 12B is a cross-sectional view of the coil component shown in FIG. 12A taken along line XIIb-XIIb. It is.
FIG. 13 is a plan view of a surface-mounted coil component according to a sixth embodiment.
FIG. 14 is a plan view of a surface-mounted coil component according to a seventh embodiment.
15 is an explanatory diagram for explaining a method of attaching the outer core 14 to the drum core 12. FIG.
FIG. 16 is a graph showing DC superposition characteristics of a surface mount coil.
FIG. 17 is a plan view and a partially enlarged view showing a conventional surface mount type coil component.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Surface mount type coil components, 11 ... Flat winding, 11a, 11b ... End of winding, 12 ... Drum type core, 12a ... trunk | drum, 12b, 12c ... collar part, 14 ... Exterior core, 15, 16 ... Partial core, 18 ... core gap, 21, 22 ... gap, 25, 26 ... electrode, 25a, 26a ... main body of electrode, 25b, 26b ... projection of electrode, SA ₁ ... The first surface that defines the gap, SA ₂ ... 2nd surface which defines a gap part, 45, 46 ... Cap-shaped electrode, 45h, 46h ... Hook part, 15a, 15b, 16a, 16b ... Projection part.

Claims (2)

A surface mount type coil component comprising a drum core wound with windings and an outer core surrounding the drum core around its axis,
One of the opposing surfaces of both the drum core and the exterior core has a plurality of protrusions,
The exterior core is divided into a plurality of partial cores so that the protruding portion abuts the other of the opposing surfaces.
The drum-type core is composed of a cylindrical body portion around which the winding is wound, and a pair of disk-shaped flange portions provided at both axial ends of the body portion,
The number of the protrusions interposed between each of the partial cores and the drum core is plural, and all of the protrusions extend from one of the partial cores and the flanges, and the other A core gap is formed between the partial core and the flange portion by contacting the
An adhesive is interposed between each of the partial cores and the drum core,
Each of the partial cores is arranged around the drum core so that the two tip portions thereof face each other in a plan view, and a gap portion is formed between the tip portions .
One of the opposing surfaces has two protrusions for each of the partial cores,
A surface mount type coil component characterized by that. And the center of the drum core, these two angles formed by the line connecting the projections, surface mount type coil component according to claim 1, characterized in that it is set to less than 15 degrees or more 90 °.

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