JP2004048859A

JP2004048859A - Thin shape, highly efficient motor or laminate for generator, and motor or generator

Info

Publication number: JP2004048859A
Application number: JP2002200448A
Authority: JP
Inventors: Mitsunobu Yoshida; 吉田　光伸; Nobuhiro Maruko; 丸子　展弘; Hiroshi Watanabe; 渡辺　洋
Original assignee: Mitsui Chemicals Inc
Current assignee: Mitsui Chemicals Inc
Priority date: 2002-07-09
Filing date: 2002-07-09
Publication date: 2004-02-12
Anticipated expiration: 2022-07-09
Also published as: JP3938338B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic laminate for a motor or a generator having a winding guide or the like manufactured by bending, by realizing a heat treatment for developing magnetic characteristics, simultaneously maintaining excellent magnetic characteristics of an amorphous metal thin strip for developing high magnetic characteristics and realizing a magnetic laminate having bending workability together. <P>SOLUTION: In the motor or the generator having a rotor made of a magnetic material and a stator, at least partial magnetic material of the rotor or the stator is constituted of the laminate made of the amorphous metal magnetic thin strip, and the laminate made of the amorphous metal magnetic thin strip has shape retentivity by bending working. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は産業機械分野に用いられる電動機、例えば、ＤＣブラシ付きモータ、ブラシレスモータ、ステッピングモータ、ＡＣインダクションモータ、ＡＣシンクロナスモータ、シンクロナスリラクタンスモータ、ＩＰＭモータ、ＳＰＭモータに関し、特に、薄型、高効率が要求される、カード型ハードディスク用スピンドルモータ等の薄型要求の強いステータに用いられる磁性積層板および、それを用いた電動機及び発電機に関する。
【０００２】
【従来の技術】
近年、ノートパソコンや、ＰＤＡ等の携帯機器等の普及、及び携帯機器の高性能化に伴い、携帯機器の記録装置として、ＣＤ−ＲＯＭドライブや、ＤＶＤ−ＲＯＭドライブや、ハードディスクドライブの小型化、薄型化、高効率化が求められている。このような記録装置において数多く使用される電動機においては、さらなる高効率化および、さらなる薄型化が強く望まれている。
【０００３】
従来の電動機または発電機に使用される磁性コアは、渦電流損失を減らすため、極力薄い磁性薄板が望まれてきた。しかしながら、現状では、珪素鋼板、電磁軟鉄、パーマロイなどが主に使用されており、これらの多結晶金属系の材料は鋳造法によってインゴットが作製され、その後熱間加工、冷間加工を経て必要な厚さの板材に加工されるが、材料の脆性等から、最薄のものでも０．１ｍｍ程度と厚さに限界があった。
【０００４】
一方、磁性コアの材料として、Ｆｅ系非晶質金属薄帯、Ｃｏ系非晶質金属薄帯等の磁性材料は、磁気的特性（鉄損、最大磁束密度、透磁率）は電磁鋼板と同等かそれを上回る特性をもち、厚さは１０μｍ〜３０μｍの薄帯が製品として入手可能となっている。そこで、モータの高効率化及び、モータの薄型化の鍵となる材料として期待されている。
しかしながら、Ｆｅ系非晶質金属薄帯、Ｃｏ系非晶質金属薄帯等の磁性材料は、磁気特性を発現させるためには２００℃〜５００℃の高温の熱処理が必要であり、熱処理後の薄帯は脆く、形状加工や一体積層時に大きな応力が材料に加わると、欠け、割れ、等が発生し、電動機コア形状の積層体の実現は困難であった。
【０００５】
また非晶質金属の優れた特性のひとつである高強靭性、強いばね性、高硬度が欠点となり、曲げ加工による形状保持が困難であった。このため、特に薄型モータのステータコアを実現する上で重要な、従来のモータ用材料であるケイ素鋼板等などで作製される、図１に示すようなステータに施される巻線ガイド用の曲げ加工を、非晶質金属の積層体に行うことは困難であった。そのため、巻線ガイド板を新たにモータコアの上下面に付与したりすることが必要となり、樹脂による厚み増大、工程数が増大するという問題が生じていた。
【０００６】
【発明が解決しようとする課題】
従って、本発明の目的は、Ｆｅ系非晶質金属薄帯、Ｃｏ系非晶質金属薄帯等の磁性積層板の上記問題を解決することである。すなわち磁気特性発現のための熱処理を実現し、高磁気特性を発現させた非晶質金属薄帯の優れた磁気特性を維持すると同時に、曲げ加工性を併せ持つ磁性積層板を実現し、曲げ加工により作製された巻線ガイド等を有する電動機または発電機用磁性積層体を提供することである。
【０００７】
【課題を解決するための手段】
このような課題を解決するために、本発明の電動機または発電機用磁性積層板は、従来からの樹脂の物性を見直し、さらに積層一体化工程、熱処理工程、モータのステータの加工工程を見なおし、そして、鋭意研究の結果、用いる樹脂の物性値およびその値が本発明の範囲の樹脂を選ぶことで、非晶質金属薄帯からなる積層板が可能となり、さらに耐熱樹脂のガラス転移温度以上の温度で磁性積層体を加熱した後、プレス成形することで、所望の形状の曲げ加工が可能となった。さらに非晶質金属の磁気特性発現のため、熱処理温度よりも高い温度域での耐熱性を有する樹脂を使用することで、非晶質金属積層体の熱処理が可能となり、磁気特性を著しく向上した電動機または発電機用の積層磁性積層板を提供できることが明らかとなった。
【０００８】
具体的には、磁性積層板を構成する樹脂が、熱可塑性を有し、さらに窒素雰囲気気流下３００℃、１時間の熱履歴を経た際の熱分解による樹脂の重量減少率が１重量％以下である樹脂を使用することにより、非晶質金属の磁性積層板において、熱処理後でも積層間の剥離のない、優れた磁気特性を有する積層体が得られる。さらに熱可塑性樹脂のガラス転移点温度以上に磁性積層体を加熱し、所望の形状にプレス成形した後、ガラス転移点以下の温度までその形状を維持することで、非晶質金属でも所望の曲げ加工ができることを見出し、非晶質金属からなる磁性積層体においても巻線ガイド等の成型加工が可能となった。さらに非晶質金属の磁気特性の発現のための、２００℃〜５００℃までの熱処理が可能で、良好な磁気特性を発現できることを見出した。
本発明は、このような知見に基づくものであり、本発明によれば、電動機を構成するロータ、またはステータの磁性積層体部分が、磁気的特性の優れた非晶質金属磁性薄帯からなる積層体より構成され、前記積層体が、熱可塑性を有し、さらに窒素雰囲気下３００℃、１時間の熱履歴を経た際の熱分解による重量減少率が１重量％以下である特性をそなえた高耐熱の熱可塑性樹脂層と非晶質金属磁性薄帯層を有する磁性基材から構成されており、高耐熱熱可塑性樹脂のガラス転移温度以上に、磁性積層体を加熱し、プレス成形後、ガラス転移温度以下までその形状を維持することで、所望の曲げ加工が可能であることを特徴としている。さらに、本発明の磁性積層体を用いることで、巻線ガイド等の曲げ加工を施した非晶質金属薄帯からなるモータ用ステータコアを実現することが可能となった。
すなわち、本発明は以下に記載した事項により特定される。
（１）磁性材料からなるロータと、ステータを備えた電動機または発電機において、ロータまたはステータの少なくとも１部の磁性材料が、非晶質金属磁性薄帯からなる積層体より構成され、前記非晶質金属磁性薄帯からなる積層体が曲げ加工による形状保持性を有していることを特徴とする電動機。
（２）上記磁性材料が、非晶質金属磁性薄帯層と熱可塑性樹脂層が交互に積層されていることを特徴とする（１）記載の発動機。
（３）上記熱可塑性樹脂が　窒素雰囲気気流下３００℃、１時間の熱履歴を経た際の熱分解による樹脂の重量減少率が１重量％以下であることを特長とする上記（１）および（２）記載の電動機または発電機用磁性積層板。
（４）非晶質金属磁性薄帯材料がＦｅ系非晶質金属薄帯、或いはＣｏ系非晶質金属薄帯であることを特徴とする上記（１）〜（３）記載の電動機。
【０００９】
【発明の実施の形態】
以下、本発明について具体的に説明する。
【００１０】
本発明に係わる電動機または発電機用磁性積層板は、非晶質金属薄帯の原反からロールコータなどのコーティング装置を用いて非晶質金属薄帯上に液状の高耐熱熱可塑性樹脂の塗膜を作り、これを乾燥させて非晶質金属薄帯に高耐熱性熱可塑性樹脂を付与する方法で作製することができる。
【００１１】
非晶質金属薄帯に高耐熱熱可塑性樹脂を付与した多層構造の磁性基材を作製する場合、多層コーティング方法や単一または多層コーティング基材を加圧、例えば熱プレスや熱ロールなどにより積層することができる。
【００１２】
加圧時の温度は高耐熱樹脂の種類により異なるが、概ね、硬化物のガラス転移温度以上で軟化もしくは溶融する温度近傍で積層接着することが好ましい。
耐熱性樹脂を付与した非晶質金属薄帯は、目的とする電動機または発電機用磁性コアに使用されるように所望の形状、例えば、図２に示すようなステータコアの形状に加工される。形状加工方法としては、プレス打ち抜き加工、放電ワイヤーカット加工、レーザー切断加工、ウォータジェット加工方法等の精密切断加工の手法が適用できる。またこの加工は非晶質金属薄帯一枚のとき、または積層一体化した後の複数枚でも可能である。
また、電動機用磁性コアのような積層構造にする場合、高い機械強度が要求され、磁性薄板間の高い密着性を実現する点から、本発明に用いる耐熱性樹脂は熱硬化性樹脂よりも非熱硬化性樹脂、例えば高耐熱熱可塑性樹脂を用いることが好ましい。
さらに磁性積層体を加熱し、耐熱樹脂を軟化させた後、プレス成形後冷却し、プレス成型形状を維持することで、所望の曲げ形状を加工することが可能となり、巻線ガイド等を形成することが可能となる。
形状加工した後に非晶質金属薄帯の磁気特性を発現させるために最適熱処理が施される。通常、磁性材料の熱処理温度は、少なくとも２００℃〜５００℃の高温であるため、熱可塑性、耐熱性樹脂は、非晶質金属薄帯の最適な磁気特性を発現させるために必要な熱処理温度に十分耐える耐熱性の高い樹脂を選択する必要がある。したがって、室温からの重量減少が１％となる温度が空気中において３５０℃以上を持つ高耐熱熱可塑性樹脂を磁性薄板に付与した磁性基材の積層体とすることで２００℃〜５００℃の熱処理後も非晶質金属薄帯との接着強度が保たれるとともに、磁性薄板の最適熱処理温度で熱処理することができるため優れた磁気特性を供することができる。
さらに本発明の詳しい説明を行う。
【００１３】
（非晶質金属薄帯）
本発明の磁性基材に使用される非晶質金属薄帯に用いられる磁性材料としては、Ｆｅ系、Ｃｏ系の非晶質金属薄帯が用いられる。これらの非晶質金属薄帯は、通常溶融金属を急冷ロールを用いて、急冷して得られる。通常は１０〜５０μｍの厚さであり、好ましくは１０〜３０μｍの厚さの薄帯が用いられる。Ｆｅ系非晶質金属材料としては、Ｆｅ−Ｂ―Ｓｉ系、Ｆｅ−Ｂ系、Ｆｅ−Ｐ−Ｃ系などのＦｅ−半金属系非晶質金属材料や、Ｆｅ−Ｚｒ系、Ｆｅ−Ｈｆ系、Ｆｅ−Ｔｉ系などのＦｅ−遷移金属系非晶質金属材料を挙げることができる。Ｃｏ系非晶質金属材料としてはＣｏ−Ｓｉ−Ｂ系、Ｃｏ−Ｂ系などの非晶質金属材料が例示できる。好ましくはＦｅ−Ｓｉ−Ｂ系においては、Ｆｅ_７８Ｓｉ_９Ｂ_１３（ａｔ％）、Ｆｅ_７８Ｓｉ_１０Ｂ_１２（ａｔ％）などが挙げることができる。
【００１４】
（高耐熱熱可塑性樹脂）
本発明の非晶質金属層の層間用いられる樹脂は、積層体を加熱した後、プレス成型を行えることが必須であるため、樹脂に要求される第一の特性としては熱可塑性を有することである。さらに非晶質金属薄帯の磁気特性を向上させる最適熱処理温度で熱処理される場合があるので、当該熱処理温度で熱分解の少ない材料を選定することが必要になる。非晶質金属薄帯の熱処理温度は、非晶質金属薄帯を構成する組成および目的とする磁気特性により異なるが、良好な磁気特性を向上させる温度は概ね２００〜５００℃の範囲にあり、さらに好ましくは３００℃〜５００℃の範囲である。
【００１５】
本発明に用いられる樹脂としては、熱可塑性、非熱可塑性、熱硬化性樹脂を挙げることができるが、ガラス転位温度以上で、樹脂を溶融させプレス成型による曲げ加工程を行うことができる、熱可塑性樹脂を用いるのが好ましい。
【００１６】
よって、熱可塑性樹脂の中でもさらに高耐熱性樹脂を用いることで、前記非晶質金属薄帯の少なくとも一部に耐熱性樹脂を付与した後、もしくは耐熱性樹脂の前駆体を付与し該耐熱性樹脂を形成した後、この磁性基材を積層し、磁性基材の積層体を得ることができる。
本発明に用いられる樹脂としては、前処理として１２０℃で４時間乾燥を施し、その後、窒素雰囲気下、３００℃で１時間保持した際の重量減少量を、ＤＴＡ−ＴＧを用いて測定され、通常１％以下、好ましくは０．３％以下であるものが用いられる。
具体的な樹脂の例としては、ポリイミド系樹脂、ケイ素含有樹脂、ケトン系樹脂、ポリアミド系樹脂、液晶ポリマー、ニトリル系樹脂、チオエ−テル系樹脂、ポリエステル系樹脂、アリレ−ト系樹脂、サルホン系樹脂、イミド系樹脂、アミドイミド系樹脂を挙げることができる。これらのうちポリイミド系樹脂、スルホン系樹脂、アミドイミド系樹脂を用いるのが好ましく。
本発明に用いられる樹脂は、上記の性質に加えて下記の特性を兼ね備えている樹脂であることがさらに好ましい。
▲１▼ガラス転移温度が１２０℃〜２５０℃である。
▲２▼窒素雰囲気下３００℃、１時間の熱履歴を経た後の引っ張り強度が３０ＭＰａ以上である。
▲３▼溶融粘度が１０万Ｐａ・ｓである温度が、２５０℃以上４００℃以下であり、さらに好ましくは３００℃以下、さらに好ましくは２５０℃以下である。
▲４▼４００℃から１２０℃まで０．５℃／分の一定速度で降温した後、樹脂中の結晶物による融解熱が１０Ｊ／ｇ以下である。
【００１７】
（樹脂付与工程）
本発明において非晶質金属薄帯に樹脂を付与させた薄帯を磁性基材と定義する。ここでは非晶質金属薄帯に樹脂を付与させる樹脂は、非晶質金属薄帯の片面のみ、または、両面の少なくとも一部に付与する。この場合、付与する面において均一にむらなく塗膜されることが好ましいが、例えば、短冊状コアの場合、切断部分ではない部分等は加工時に接着強度が十分であればよく、非晶質金属薄帯間の接着が得られるように部分的に熱可塑性、耐熱性樹脂が付与されていれば良い。また、積層体を形状加工する場合等で接着強度が必要となる場合には、薄帯の片面または両面に全面に塗布されていることが望ましい。
【００１８】
本発明における非晶質金属薄帯の片面または両面の少なくとも一部に熱可塑性、耐熱性樹脂を付着する場合、粉末状樹脂、もしくは溶媒に樹脂を溶解させた溶液または、ペースト状の形態がある。樹脂を溶解させた溶液を用いる場合は、ロ−ルコ−タなどを用いて非晶質金属薄帯に付与して行うことが代表的である。この場合、付与工程で用いる溶液の粘度は、０．００５Ｐａ・ｓ以下の粘度では、粘性が低くなり過ぎるため非晶質金属薄帯上から流れてしまい磁性基材上に十分な塗膜量が得られず、極めて薄い塗膜になってしまう。また、この場合膜厚を厚くするために、付与速度を極めて遅くすると何度も重ね塗りが必要になるため、生産効率の低下が生じ実用的ではない。一方、粘度が、２００Ｐａ・ｓ以上になると、高粘度のため、非晶質金属薄帯上に薄い塗膜を形成するための膜厚の制御が極めて難しくなる。したがって、樹脂を溶媒に溶解させた溶液による付与の場合、付与時の溶液粘度は０．００５〜２００Ｐａ・ｓの濃度範囲が好ましい。さらには、０．０１〜５０Ｐａ・ｓの濃度範囲が好ましく、より好ましくは、０．０５〜５Ｐａ・ｓの範囲にある方が良い。
【００１９】
本発明における樹脂を溶媒に溶解させた溶液の付与方法としては、コ−タを用いた方法、例えば、ロ−ルコ−タ法、グラビアコ−タ法、エアドクタコ−タ法、ブレ−ドコ−タ法、ナイフコ−タ法、ロッドコ−タ法、キスコ−タ法、ビ−ドコ−タ法、キャストコ−タ法、ロ−タリ−スクリ−ン法や、液状樹脂中に非晶質金属薄帯を浸漬しながらコ−テイングする浸漬コ−テング方法、液状樹脂を非晶質金属薄帯にオリフィスから落下させコ−テイングするスロットオリフィスコ−タ法などで行うことができる。その他、バ−コ−ド方法や霧吹きの原理を用いて液状樹脂を霧上に非晶質金属薄帯に吹き付けるスプレ−コ−ティング法や、スピンコ−テング法、電着コ−テング法、あるいはスパッタ法のような物理的な蒸着法、ＣＶＤ法のような気相法など非晶質金属薄帯上に耐熱性樹脂を付与できる方法なら如何なる方法を用いても良い。
【００２０】
また、一部、熱可塑性、耐熱性樹脂を付与するには、塗膜パターンの溝を加工したグラビアヘッドを用いて、グラビアコータ法で行うことができる。
【００２１】
また、本発明における非晶質金属薄帯の片面または両面の少なくとも一部に付着させる樹脂として、ペ−スト状樹脂を使用する場合は、主として非晶質金属薄帯と非晶質金属薄帯など複数の非晶質金属薄帯を積層する場合に用いることが好ましい。そのため、樹脂は液状樹脂のような流動性よりは仮接着固定や仮止めができる粘度があれば良く、ポッティングや刷毛塗りなどの方法で付与することができる。したがって、樹脂の粘度としては、５Ｐａ・ｓ以上の粘度であることが好ましい。一方、粉末状の樹脂を用いる場合は、例えば、金型を用いて非晶質金属薄帯の積層体を作製する時に粉末状・ペレット状の樹脂を充填または散布して熱プレス成型などにより非晶質金属薄帯の積層体を作製する場合に用いることができる。
【００２２】
さらに、本発明で使用するポリイミドを用いる方法として、溶媒可溶性のポリイミド若しくはその両末端に反応性の官能基（以下「付加反応基」）を導入したものを用いることもできる。すなわち、可溶性ポリイミドを溶剤に溶かして液状とし、適切な粘度に調整して、非晶質金属薄帯に付与し、加熱して溶剤を揮発して耐熱性樹脂を形成する方法が用いられる。
次に本発明による積層体を用いて電動機の磁性コアを作製する工程について説明する。但し、作製する工程は巻線加工までとする。また本発明における工程は以下に説明する順番とは限らず、以下の各工程の組み合わせることが可能である。
【００２３】
（積層一体加工工程）
本発明おける、非晶質金属薄帯に予め高耐熱熱可塑性樹脂または高耐熱熱可塑性樹脂の前駆体を付与した磁性基材を用いて積層する製造方法について詳細に説明する。
【００２４】
非晶質金属薄帯に高耐熱熱可塑性樹脂を付与した磁性基材の積層体の作製工程は、多層コ−ティング方法や単一または多層コ−ティング基材を加圧、例えば熱プレスや熱ロ−ルなどにより積層することができる。加圧時の温度は耐熱樹脂の種類により異なるが、概ね、硬化物のガラス転移温度（Ｔｇ）以上で軟化もしくは溶融する温度近傍で積層およびプレスすることが好ましい。
【００２５】
非晶質金属薄帯の積層体の作製は、多層コ−ティング方法あるいは熱プレス、または熱ロ−ル、高周波溶着などで積層接着することで積層構造を自由に設計することができる。
【００２６】
本発明の非晶質金属薄帯積層体は、非晶質金属薄帯を積み重ね、熱可塑性、耐熱性樹脂または熱可塑性、耐熱性樹脂の前駆体を含浸させて樹脂化することで積層体を作製する方法があるが、好ましくは、非晶質金属薄帯に予め熱可塑性、耐熱性樹脂または熱可塑性、耐熱性樹脂の前駆体を付与した磁性基材を用い、この基材を積層接着して積層体を作製する方法が望ましい。
【００２７】
（形状加工工程）
本発明の電動機用磁性コアに形状加工する場合は、プレス打抜き加工、放電ワイヤーカット加工、レーザー切断加工等の精密切断加工の方法が適用でき、これに限定されるものではない。これらの方法の中でも、好ましくはプレス打抜き加工が、量産時に加工単価が低い点で望ましい。形状加工は非晶質金属薄帯１枚のときでも可能であり、また積層一体化した後で、複数枚からなる積層体を同時に形状加工することも可能である。加工単価を低くする上では複数枚を同時に形状加工することが望ましい。
【００２８】
（曲加工工程）
本発明の磁性積層体は、熱可塑性樹脂を非晶質金属薄帯層間に用いることで、熱可塑性樹脂に流動性が生じるまで加熱し、磁性積層体を構成する非晶質金属薄帯が相互にずれることが可能となり、磁性積層板として、曲げ変形が可能となる。この状態のときに、所望の形状の金型形状にプレス成形後、熱可塑性樹脂の流動性がなくまるまで冷却することで、所望の形状を維持することが可能となる。この方法を用いることで、薄型モータ等に施される、巻線ガイド用の曲げ形状に加工することも可能となる。
【００２９】
（熱処理工程）
本発明の非晶質金属薄帯の磁気特性を向上させるために、行われる熱処理である。非晶質金属薄帯の熱処理温度は、非晶質金属薄帯を構成する組成および目的とする磁気特性により異なるが、通常、不活性ガス雰囲気下もしくは真空中で行われ、良好な磁気特性を向上させる温度は概ね３００〜５００℃であり、好ましくは３５０℃から４５０℃で行わる。
【００３０】
（巻線工程）
本発明の電動機用磁性コアは、例えば、被覆銅線をステータ−コア形状の被覆に巻く場合、巻き方は集中巻、分布巻など可能である。さらに被覆銅線を巻いた後、被覆銅線の引き出し線を円形のステータ−コアに沿って這わせる必要があるが、そのときステータ−コアに、被覆銅線の位置を決める突起となる巻線ガイドがあると、被覆銅線のはみ出しが防止でき、安定にステータ−コアの巻線製造が可能となる。
【００３１】
本発明の磁性基材モータ用磁性積層板は、以上の工程の組み合わせから作製することが可能となる。各工程の代表的な組み合わせを以下に示す。
パターン１：
（樹脂付与工程）→（積層一体加工工程）→（形状加工工程）→（曲加工工程）→（熱処理工程）→（巻線工程）
パターン２：
（樹脂付与工程）→（形状加工工程）→（積層一体加工工程）→（曲加工工程）→（熱処理工程）→（巻線工程）
パターン１の工程は、非晶質金属に樹脂を付与した磁性基材を、複数枚重ねて、熱プレス等の方法で積層一体化し、平板とする。さらにプレス打ち抜き加工等でモータコア形状に加工を行い、さらに樹脂のガラス転位温度以上の温度に加熱後、プレスによる曲加工により巻線ガイド等の施し、さらに非晶質金属の磁気特性を発現するための熱処理を行い。最後に巻線を施す。パターン１は、複数枚を一度にプレス抜きすることができるため、コスト低減効果が著しく、大量生産に最も適した加工工程である。本工程を熱硬化性樹脂を用いた磁性積層板によって行う場合、積層一体化時に樹脂が硬化してしまうため、その後の曲げ加工時に加熱しても樹脂の流動性は得られず、曲げ加工はできない。
【００３２】
パターン２の工程は、非晶質金属に樹脂を付与した磁性基材を、１枚ずつプレス打ち抜き加工等でモータコア形状に加工を行った後、複数枚重ねて、熱プレス等の方法で積層一体化し、モータコア板とする。さらに樹脂のガラス転位温度以上の温度に加熱後、曲加工により巻線ガイド等の施す。積層一体化加工と曲加工は同金型で同時に行うことが可能である。さらに非晶質金属の磁気特性を発現するための熱処理を行い。最後に巻線を施す。
【００３３】
【実施例】
以下、本発明の実施例について示す。
【００３４】
［実施例１］非晶質金属薄帯にハネウェル社製、Ｍｅｔｇｌａｓ：２６０５ＴＣＡ（商品名）、幅約１７０ｍｍ、厚み約２５μｍのＦｅ_７８Ｓｉ_９Ｂ_１３（ａｔ％）の組成を持つ非晶質金属薄帯（図３−１）を使用した。この薄帯の両面全面に約０．３Ｐａ・ｓの粘度のポリアミド酸溶液を付与し、１５０℃で溶媒を揮発させた後、２５０℃でポリイミド樹脂とし、薄板の両面に厚さ約２ミクロンの耐熱性熱可塑性樹脂（ポリイミド樹脂）（図３−２）を付与した非晶質金属薄帯を作製した。ジアミンに３、３’−ジアミノジフェニルエーテル、テトラカルボン酸二無水物にビス（３、４−ジカルボキシフェニル）エーテルニ無水物により得られるポリイミドの前駆体であるポリアミド酸を用い、ジメチルアセトアミドの溶媒に溶解して非晶質金属薄帯上に塗布し、非晶質金属薄帯上で加熱した。この樹脂は本発明の請求項２、３記載の特性値をすべて満足していた。
【００３５】
次にこの樹脂を付与した磁性基材を５０枚重ねて、熱プレスにより２７０℃３０分で積層一体化を行い、磁性積層板とした。
【００３６】
さらに５０枚重ねた磁性積層板から、図２に示す形状のモータ用ステータを作製するため、外径５０ｍｍ内径４０ｍｍのステータ−コア形状をプレス打ち抜きで１度に抜いた。　巻線ガイドの曲げ加工を行う金型にセットし、加熱後、２７０℃に達した段階で、プレス成型により曲げ加工を施した。さらに加熱し、磁気特性発現のため３５０℃２ｈｒ熱処理した。その結果、厚みは１．３７ｍｍとなり、従来のケイ素鋼鈑材料による積層体の占積率（９５％）程度と同程度の非常に高い占積率（９１％）を実現した。但し、ここでいう占積率とは次式で定義する式により計算した値を用いた。
（占積率（％））＝（（（非晶質金属薄帯厚さ）×（積層枚数））／（積層後の積層体厚さ））＊１００
熱処理後も、積層体に剥がれ、そり等はなく、占積率は９１％を維持した。また、ＪＩＳ　Ｈ７１５３の「アモルファス金属磁心の高周波磁心損失試験方法」に準じた磁心寸法（外径５０ｍｍ内径４０ｍｍ）の円環をハサミで切り抜き、さきのモータ用ステータと同様のプロセスで、５０枚積層したリングを作製し、１０００Ｈｚの交流磁場１［Ｔ］を印加したときのＢＨヒステリシスループから鉄損を測定した。その結果、鉄損は８．５［Ｗ／ｋｇ］であり、従来モータに用いられているケイ素鋼鈑と比較し、鉄損が２分の１から３分の１と低損失で良好な磁気特性を実現していることを確認した。
【００３７】
さらに作製したステータコアに巻線を施したところ、曲げ加工により形成した巻線ガイドにより、巻線の引き出し線が容易に巻線ガイドに沿って安定的かつ短時間に配線することが可能となった。
【００３８】
［実施例２］非晶質金属薄帯にハネウェル社製、Ｍｅｔｇｌａｓ：２６０５ＴＣＡ（商品名）、幅約１７０ｍｍ、厚み約２５μｍのＦｅ_７８Ｓｉ_９Ｂ_１３（ａｔ％）の組成を持つ非晶質金属薄帯（図３−１）を使用した。この薄帯の両面全面に約０．３Ｐａ・ｓの粘度のポリアミド酸溶液を付与し、１５０℃で溶媒を揮発させた後、２５０℃でポリイミド樹脂とし、薄板の両面に厚さ約２ミクロンの耐熱性熱可塑性樹脂（ポリイミド樹脂）（図３−２）を付与した非晶質金属薄帯を作製した。ジアミンに３、３’−ジアミノジフェニルエーテル、テトラカルボン酸二無水物にビス（３、４−ジカルボキシフェニル）エーテルニ無水物により得られるポリイミドの前駆体であるポリアミド酸を用い、ジメチルアセトアミドの溶媒に溶解して非晶質金属薄帯上に塗布し、非晶質金属薄帯上で加熱した。この樹脂は本発明の請求項２、３記載の特性値をすべて満足していた。
【００３９】
この薄帯から、図２に示す形状のモータ用ステータを作製するため、外径５０ｍｍ内径４０ｍｍのステータ−コア形状に５０枚をプレス打ち抜き、５０枚重ねた後、積層一体化と巻線ガイドの曲げ加工を行う金型にセットし、２７０℃で３０分間熱圧着することで、巻線ガイド用の曲加工と積層一体化を同時に行い図４に示すモータ用ステータとした。さらに積層一体化と巻線ガイドの曲げ加工を行った金型にセットしたまま、磁気特性発現のため３５０℃２ｈｒ熱処理した。その結果、厚みは１．３７ｍｍとなり、従来のケイ素鋼鈑材料による積層体の占積率（９５％）程度と同程度の非常に高い占積率（９１％）を実現した。但し、ここでいう占積率とは次式で定義する式により計算した値を用いた。
【００４０】
（占積率（％））＝（（（非晶質金属薄帯厚さ）×（積層枚数））／（積層後の積層体厚さ））＊１００
熱処理後も、積層体に剥がれ、そり等はなく、占積率は９１％を維持した。また、ＪＩＳ　Ｈ７１５３の「アモルファス金属磁心の高周波磁心損失試験方法」に準じた磁心寸法（外径５０ｍｍ内径４０ｍｍ）の円環をハサミで切り抜き、さきのモータ用ステータと同様のプロセスで、５０枚積層したリングを作製し、１０００Ｈｚの交流磁場１Ｔを印加したときのＢＨヒステリシスループから鉄損を測定した。その結果、鉄損は８．５［Ｗ／ｋｇ］であり、従来モータに用いられているケイ素鋼鈑と比較し、鉄損が２分の１から３分の１と低損失で良好な磁気特性を実現していることを確認した。
【００４１】
さらに作製したステータコアに巻線を施したところ、曲げ加工により形成した巻線ガイドにより、巻線の引き出し線が容易に巻線ガイドに沿って安定的かつ短時間に配線することが可能となった。
【００４２】
［比較例１］　実施例１と同様にモータ用ステータコアを作製した。但し、使用する樹脂を高耐熱熱硬化性樹脂（デュポン社製カプトンと同一構造体）を用いたところが異なる。２８０℃で樹脂を熱硬化させ、積層一体化し、磁性積層板とした後にモータ用ステータコア形状にプレス打ち抜きした。さらに巻線ガイド用の曲加工を行う金型にセットし、３００℃に加熱したが、樹脂の流動性を得ることはできず、巻線ガイドの形状加工時にできなかった。このため巻線ガイドの突起がなく、巻線に使用したφ０．３ｍｍ銅線の巻線の引き出し線がステータコアからはみ出し、巻線時に、巻線の引き出し線の位置が定まらず、巻線作業時に断線が生じ、安定な巻線が困難であった。
【００４３】
［比較例２］　実施例１と同様の磁性基材とモータ用ステータコアを作製した。熱処理後、曲げ加工による巻線ガイドは施さなかったため、図５に示すように樹脂性の巻線ガイド（厚み０．４ｍｍ）を、モータ用ステータコアの両面に設けた。そのため、本樹脂性の巻線ガイド分の厚みが（０．４×２ｍｍ）厚くなり、薄型化に実施例１、２より１ｍｍ程度厚くなり、モータの薄型化において不利となった。
【００４４】
以上を下表にまとめる。
【００４５】
【表１】

【００４６】
【発明の効果】
本発明は、磁性材料からなるロータと、ステータを備えた電動機または発電機において、ロータまたはステータの少なくとも１部の磁性材料が、非晶質金属磁性薄帯からなる積層体より構成され、前記非晶質金属磁性薄帯からなる積層体が、熱可塑性を有し、さらに好ましくは窒素雰囲気気流下３００℃、２時間の熱履歴を経た際の熱分解による樹脂の重量減少率が１重量％以下であることを特長とする樹脂層と非晶質金属磁性薄帯層が交互に積層した磁性積層板とすることで以下の優れた効果を有していることが判明した。
【００４７】
１）曲加工成型性
磁性積層帯磁性積層体を加熱し、耐熱性樹脂が流動性を有した状態で曲加工し、流動性がなくなるまで冷却し形状を保持することで、所望の曲げ形状を保持することが可能となり、薄型モータ用コアに必要な巻線ガイド等を形成することが可能となる。
【００４８】
２）非晶質金属の優れた磁気特性を発現するための熱処理が可能
すなわち非晶質金属薄帯の熱処理温度下（３００℃〜５００℃）でも樹脂が熱的な分解がほとんどない。よって、樹脂の接着力と、適度な弾性率が維持され、樹脂を塗工された非晶質金属薄帯の全体の機械的強度が、熱処理時の積層一体化における圧縮応力下、あるいは熱処理後の常温下においても、非晶質金属薄帯に割れ、欠け等が生じにくくなる。その結果、Ｆｅ系非晶質金属薄帯、Ｃｏ系非晶質金属薄帯の熱処理後の脆性を克服すると同時に優れた磁気的特性の発現が可能となり、一体積層化した電動機または発電機用磁性コアの実現が可能となった。
【００４９】
３）高機械強度
また、非晶質金属薄帯に樹脂が密着してコーティングされていることで、非晶質金属薄帯内部のクラックの拡大を防止する。すなわち、電動機または発電機が回転時に生じる応力による非晶質金属薄帯部のクラックの拡大を防止し、モータとして充分な機械的強度を確保することが可能となる。
【００５０】
４）形状加工性
高機械強度を有していることから、プレス打ち抜き加工、放電ワイヤーカット加工、レーザー切断加工方法等の精密切断加工の手法がクラックの拡大、割れかけ等なく適用でき、形状設計の自由度が増し、最適な形状の磁気回路を実現することが可能となる。
【００５１】
特に、ローターやステータ−必要な、巻線を巻く櫛刃形状部分のプレス打ち抜き加工においては、通常、耐熱樹脂を塗工していないものでは、割れ、カケが多く、安定な形状加工が難しかったが、耐熱樹脂を塗工したものは、割れ、カケなく、安定に加工することが可能となった。
【００５２】
５）高占積率
熱可塑性を有する樹脂を用いると、積層一体化の時の加熱加圧時に、樹脂がで流動し、積層体の層間の空隙が減り、占積率を大幅に向上させることが可能となる。電動機または発電機において、ロータやステータの占積率を向上させることは、機器の小型化、あるいは、高出力化につながる。
【図面の簡単な説明】
【図１】従来のケイ素鋼鈑による巻線ガイドの１例を示す図
【図２】本発明の実施例１の電動機用磁性コアの形状を示す図。
【図３】本発明の実施例１の磁性基材の作製工程を示す図。
【図４】本発明の実施例１の巻線ガイドの曲げ加工を施した図
【図５】本発明の比較例２の樹脂性巻線ガイドを付与したステータコアを示す
図。
【符号の説明】
１１　　巻線
１２　　巻線ガイド
１３　　ステータコア
２１　　ステータコア
３１　　非晶質金属薄帯
３２　　耐熱性樹脂
４１　　曲げ加工した巻き線ガイド
５１　　巻線
５２　　樹脂性巻線ガイド
５３　　ステータコア[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric motor used in the field of industrial machinery, for example, a DC brushed motor, a brushless motor, a stepping motor, an AC induction motor, an AC synchronous motor, a synchronous reluctance motor, an IPM motor, and an SPM motor. The present invention relates to a magnetic laminated plate used for a stator requiring high efficiency, such as a spindle motor for a card-type hard disk, which is required to be thin, and a motor and a generator using the same.
[0002]
[Prior art]
In recent years, with the spread of portable devices such as notebook personal computers and PDAs and the high performance of portable devices, CD-ROM drives, DVD-ROM drives, and hard disk drives have been reduced in size as recording devices for portable devices. Thinning and high efficiency are required. In a motor used in such a recording apparatus in many cases, further improvement in efficiency and further reduction in thickness are strongly desired.
[0003]
For a magnetic core used in a conventional motor or generator, a magnetic thin plate as thin as possible has been desired in order to reduce eddy current loss. However, at present, silicon steel sheets, soft magnetic iron, permalloy, etc. are mainly used, and ingots of these polycrystalline metal-based materials are manufactured by a casting method, and then required after hot working and cold working. Although it is processed into a plate material having a thickness, the thickness of the thinnest plate is limited to about 0.1 mm due to the brittleness of the material.
[0004]
On the other hand, magnetic materials such as Fe-based amorphous metal ribbons and Co-based amorphous metal ribbons as magnetic core materials have the same magnetic properties (iron loss, maximum magnetic flux density, and magnetic permeability) as magnetic steel sheets. Thin strips having a thickness of 10 μm to 30 μm, which have characteristics exceeding or exceeding this, are available as products. Therefore, it is expected to be a key material for increasing the efficiency of the motor and reducing the thickness of the motor.
However, magnetic materials such as Fe-based amorphous metal ribbons and Co-based amorphous metal ribbons require high-temperature heat treatment at 200 ° C. to 500 ° C. in order to exhibit magnetic characteristics. The ribbon is brittle, and if a large stress is applied to the material during shape processing or integral lamination, chipping, cracking, and the like occur, and it has been difficult to realize a laminated body having a motor core shape.
[0005]
Further, one of the excellent characteristics of the amorphous metal, namely, high toughness, strong spring property, and high hardness, was disadvantageous, and it was difficult to maintain the shape by bending. For this reason, a bending process for a winding guide to be performed on a stator as shown in FIG. 1 made of a conventional motor material such as a silicon steel plate or the like, which is particularly important for realizing a stator core of a thin motor. Is difficult to perform on a laminate of an amorphous metal. For this reason, it is necessary to newly provide a winding guide plate to the upper and lower surfaces of the motor core, and there has been a problem that the thickness of the resin is increased and the number of steps is increased.
[0006]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to solve the above-mentioned problems of a magnetic laminated plate such as an Fe-based amorphous metal ribbon and a Co-based amorphous metal ribbon. In other words, by realizing heat treatment for the development of magnetic properties, we maintain the excellent magnetic properties of the amorphous metal ribbon that has developed high magnetic properties, and at the same time, realize a magnetic laminate that has both bending workability and bending. An object of the present invention is to provide a magnetic laminate for a motor or a generator having a manufactured winding guide or the like.
[0007]
[Means for Solving the Problems]
In order to solve such problems, the magnetic laminated plate for an electric motor or a generator according to the present invention reviews the physical properties of the conventional resin, and further reviews the laminating and integrating step, the heat treatment step, and the processing step of the motor stator. And, as a result of intensive research, the physical properties of the resin to be used and the values thereof are selected within the range of the present invention, whereby a laminated plate made of an amorphous metal ribbon can be obtained. After the magnetic laminate was heated at the temperature described above, press molding was performed, thereby enabling bending of a desired shape. Furthermore, by using a resin having heat resistance in a temperature range higher than the heat treatment temperature, the heat treatment of the amorphous metal laminate can be performed, and the magnetic characteristics have been significantly improved. It has been clarified that a laminated magnetic laminate for an electric motor or a generator can be provided.
[0008]
Specifically, the resin constituting the magnetic laminate has thermoplasticity, and the weight loss rate of the resin due to thermal decomposition after passing through a heat history of 300 ° C. for 1 hour under a nitrogen atmosphere is 1% by weight or less. By using the resin of (1), a laminated body having excellent magnetic properties without peeling between laminations even after heat treatment can be obtained in a magnetic laminated plate of an amorphous metal. Further, the magnetic laminate is heated to a temperature equal to or higher than the glass transition temperature of the thermoplastic resin and press-molded into a desired shape. They found that processing was possible, and it was possible to form a winding guide and the like even in a magnetic laminate made of an amorphous metal. Furthermore, it has been found that heat treatment at a temperature of 200 ° C. to 500 ° C. for expressing the magnetic properties of the amorphous metal is possible, and good magnetic properties can be exhibited.
The present invention is based on such knowledge, and according to the present invention, a rotor constituting a motor, or a magnetic laminated body portion of a stator is made of an amorphous metal magnetic ribbon having excellent magnetic properties. The laminate is characterized in that the laminate has thermoplasticity and further has a weight reduction rate of 1% by weight or less due to thermal decomposition after a heat history of 300 ° C. for 1 hour in a nitrogen atmosphere. It is composed of a magnetic substrate having a high heat-resistant thermoplastic resin layer and an amorphous metal magnetic ribbon layer, and is heated to a temperature higher than the glass transition temperature of the high heat-resistant thermoplastic resin. By maintaining the shape below the glass transition temperature, a desired bending process is possible. Furthermore, by using the magnetic laminate of the present invention, it has become possible to realize a motor stator core made of an amorphous metal ribbon subjected to a bending process such as a winding guide.
That is, the present invention is specified by the matters described below.
(1) In a motor or a generator provided with a rotor made of a magnetic material and a stator, at least a part of the magnetic material of the rotor or the stator is made of a laminate made of an amorphous metal magnetic ribbon, and An electric motor characterized in that a laminated body made of a thin metallic magnetic ribbon has shape retention by bending.
(2) The motor according to (1), wherein the magnetic material is formed by alternately laminating amorphous metal magnetic ribbon layers and thermoplastic resin layers.
(3) The above-mentioned (1) and (1), wherein the thermoplastic resin has a weight loss ratio of 1% by weight or less due to thermal decomposition when subjected to a thermal history of 300 ° C. for 1 hour under a nitrogen atmosphere. 2) The magnetic laminate for an electric motor or a generator according to the above.
(4) The electric motor according to the above (1) to (3), wherein the amorphous metal magnetic ribbon material is an Fe-based amorphous metal ribbon or a Co-based amorphous metal ribbon.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described specifically.
[0010]
The magnetic laminate for an electric motor or a generator according to the present invention is obtained by coating a liquid high heat-resistant thermoplastic resin on an amorphous metal ribbon using a coating device such as a roll coater from an amorphous metal ribbon. The film can be produced by a method of forming a film, drying the film, and applying a highly heat-resistant thermoplastic resin to the amorphous metal ribbon.
[0011]
When producing a magnetic substrate with a multilayer structure in which a high heat-resistant thermoplastic resin is applied to an amorphous metal ribbon, a multilayer coating method or a single or multilayer coated substrate is pressed, for example, laminated by a hot press or a hot roll. can do.
[0012]
Although the temperature at the time of pressurization differs depending on the type of the high heat-resistant resin, it is preferable that the lamination is performed in the vicinity of a temperature at which the cured product is softened or melted above the glass transition temperature.
The amorphous metal ribbon provided with the heat-resistant resin is processed into a desired shape, for example, a stator core shape as shown in FIG. 2 so as to be used for a target magnetic core for an electric motor or a generator. As the shape processing method, a precision cutting method such as press punching, discharge wire cutting, laser cutting, or water jet processing can be applied. This processing can be performed on a single amorphous metal ribbon or on a plurality of sheets after lamination and integration.
In addition, when a laminated structure such as a magnetic core for an electric motor is used, high mechanical strength is required, and a high heat-resistant resin used in the present invention is less heat-resistant than a thermosetting resin in terms of realizing high adhesion between magnetic thin plates. It is preferable to use a thermosetting resin, for example, a high heat-resistant thermoplastic resin.
Furthermore, after heating the magnetic laminate and softening the heat-resistant resin, it is cooled after press forming, and by maintaining the press-formed shape, it becomes possible to process a desired bent shape, thereby forming a winding guide and the like. It becomes possible.
After the shaping, an optimal heat treatment is performed to develop the magnetic properties of the amorphous metal ribbon. Usually, the heat treatment temperature of the magnetic material is a high temperature of at least 200 ° C. to 500 ° C., so that the thermoplastic and heat-resistant resin are heated to a heat treatment temperature necessary for developing the optimal magnetic properties of the amorphous metal ribbon. It is necessary to select a resin with high heat resistance that can withstand sufficiently. Therefore, a heat treatment at 200 ° C. to 500 ° C. is performed by forming a laminated body of a magnetic base material in which a highly heat-resistant thermoplastic resin having a temperature at which the weight loss from room temperature is 1% is 350 ° C. or more in air is applied to a magnetic thin plate. After that, the adhesive strength to the amorphous metal ribbon is maintained, and the magnetic thin plate can be heat-treated at the optimum heat-treating temperature, so that excellent magnetic properties can be provided.
Further, the present invention will be described in detail.
[0013]
(Amorphous metal ribbon)
As the magnetic material used for the amorphous metal ribbon used in the magnetic substrate of the present invention, Fe-based and Co-based amorphous metal ribbons are used. These amorphous metal ribbons are usually obtained by quenching molten metal using a quenching roll. Usually, the thickness is 10 to 50 μm, and preferably, a ribbon having a thickness of 10 to 30 μm is used. Examples of the Fe-based amorphous metal material include Fe-semimetal-based amorphous metal materials such as Fe-B-Si-based, Fe-B-based, and Fe-PC-based materials, Fe-Zr-based, and Fe-Hf. And Fe-transition metal based amorphous metal materials such as Fe-Ti-based and Fe-Ti-based. Examples of the Co-based amorphous metal material include Co-Si-B-based and Co-B-based amorphous metal materials. Preferably, in the Fe-Si-B system, Fe ₇₈ Si ₉ B ₁₃ (at%), Fe ₇₈ Si ₁₀ B ₁₂ (at%) and the like can be mentioned.
[0014]
(High heat resistant thermoplastic resin)
Since the resin used between layers of the amorphous metal layer of the present invention is required to be able to be press-molded after heating the laminate, the first property required for the resin is to have thermoplasticity. is there. Further, since the heat treatment may be performed at an optimum heat treatment temperature for improving the magnetic properties of the amorphous metal ribbon, it is necessary to select a material that is less thermally decomposed at the heat treatment temperature. The heat treatment temperature of the amorphous metal ribbon varies depending on the composition of the amorphous metal ribbon and the intended magnetic properties, but the temperature at which good magnetic properties are improved is generally in the range of 200 to 500 ° C. More preferably, it is in the range of 300 ° C to 500 ° C.
[0015]
As the resin used in the present invention, thermoplastic, non-thermoplastic, thermosetting resins can be mentioned, but at a glass transition temperature or higher, the resin can be melted and subjected to a bending process by press molding. It is preferable to use a plastic resin.
[0016]
Therefore, by using a highly heat-resistant resin among the thermoplastic resins, after applying a heat-resistant resin to at least a part of the amorphous metal ribbon, or by adding a precursor of the heat-resistant resin, After the resin is formed, the magnetic substrates are laminated to obtain a laminate of the magnetic substrates.
The resin used in the present invention is subjected to drying at 120 ° C. for 4 hours as a pretreatment, and thereafter, the weight loss when held at 300 ° C. for 1 hour under a nitrogen atmosphere is measured using DTA-TG, Usually, those having a content of 1% or less, preferably 0.3% or less are used.
Specific examples of the resin include a polyimide resin, a silicon-containing resin, a ketone resin, a polyamide resin, a liquid crystal polymer, a nitrile resin, a thioether resin, a polyester resin, an arylate resin, and a sulfone resin. Resins, imide resins and amide imide resins can be mentioned. Of these, it is preferable to use a polyimide resin, a sulfone resin, or an amide imide resin.
The resin used in the present invention is more preferably a resin having the following properties in addition to the above properties.
(1) The glass transition temperature is from 120 ° C to 250 ° C.
{Circle over (2)} The tensile strength after a heat history of 300 ° C. for one hour in a nitrogen atmosphere is 30 MPa or more.
{Circle around (3)} The temperature at which the melt viscosity is 100,000 Pa · s is from 250 ° C. to 400 ° C., preferably 300 ° C. or less, more preferably 250 ° C. or less.
{Circle around (4)} After the temperature is lowered from 400 ° C. to 120 ° C. at a constant rate of 0.5 ° C./min, the heat of fusion due to the crystals in the resin is 10 J / g or less.
[0017]
(Resin application step)
In the present invention, a ribbon obtained by adding a resin to an amorphous metal ribbon is defined as a magnetic substrate. Here, the resin for applying the resin to the amorphous metal ribbon is applied to only one surface of the amorphous metal ribbon or to at least a part of both surfaces. In this case, it is preferable that the coating is uniformly applied on the surface to be applied.For example, in the case of a strip-shaped core, a portion that is not a cut portion may have sufficient adhesive strength at the time of processing, and an amorphous metal It suffices that a thermoplastic or heat-resistant resin is partially applied so that adhesion between the ribbons can be obtained. Further, when adhesive strength is required, for example, when processing the shape of the laminated body, it is desirable that the adhesive be applied to one or both surfaces of the ribbon.
[0018]
When the thermoplastic or heat-resistant resin is attached to at least a part of one side or both sides of the amorphous metal ribbon in the present invention, there is a powdery resin, a solution in which the resin is dissolved in a solvent, or a paste-like form. . When a solution in which a resin is dissolved is used, it is typically applied by applying the solution to an amorphous metal ribbon using a roll coater or the like. In this case, if the viscosity of the solution used in the applying step is 0.005 Pa · s or less, the viscosity becomes too low, so that the solution flows from the amorphous metal ribbon and a sufficient coating amount on the magnetic substrate. It cannot be obtained, resulting in an extremely thin coating film. Further, in this case, if the application speed is extremely slowed down in order to increase the film thickness, it is necessary to perform recoating many times, which causes a reduction in production efficiency and is not practical. On the other hand, when the viscosity is 200 Pa · s or more, it is extremely difficult to control the film thickness for forming a thin coating film on the amorphous metal ribbon because of the high viscosity. Therefore, in the case of applying by a solution in which a resin is dissolved in a solvent, the solution viscosity at the time of application is preferably in a concentration range of 0.005 to 200 Pa · s. Further, the concentration is preferably in the range of 0.01 to 50 Pa · s, and more preferably in the range of 0.05 to 5 Pa · s.
[0019]
As a method of applying a solution in which the resin in the present invention is dissolved in a solvent, a method using a coater, for example, a roll coater method, a gravure coater method, an air doctor coater method, a blade coater Method, knife coater method, rod coater method, kiss coater method, bead coater method, cast coater method, rotary screen method, and amorphous metal ribbon in liquid resin Immersion coating method in which the resin is coated while being immersed, and a slot orifice coating method in which the liquid resin is dropped on the amorphous metal ribbon from the orifice and coated. In addition, a spray coating method in which a liquid resin is sprayed onto an amorphous metal ribbon on a mist using a bar code method or the principle of spraying, a spin coating method, an electrodeposition coating method, or Any method, such as a physical vapor deposition method such as a sputtering method, or a vapor phase method such as a CVD method, may be used as long as the heat-resistant resin can be applied to the amorphous metal ribbon.
[0020]
In addition, a part of the thermoplastic or heat-resistant resin can be imparted by a gravure coater method using a gravure head in which a groove of a coating film pattern is processed.
[0021]
When a paste-like resin is used as the resin adhered to one or both surfaces of the amorphous metal ribbon in the present invention, the amorphous metal ribbon and the amorphous metal ribbon are mainly used. It is preferably used when a plurality of amorphous metal ribbons are laminated. For this reason, the resin only needs to have a viscosity that enables temporary bonding and temporary fixing, rather than fluidity like a liquid resin, and can be applied by a method such as potting or brushing. Therefore, the viscosity of the resin is preferably 5 Pa · s or more. On the other hand, when a powdery resin is used, for example, when a laminate of an amorphous metal ribbon is produced using a mold, the resin in the form of a powder or a pellet is filled or sprayed and non-pressed by hot press molding or the like. It can be used when producing a laminate of a crystalline metal ribbon.
[0022]
Furthermore, as a method of using the polyimide used in the present invention, a solvent-soluble polyimide or a compound in which a reactive functional group (hereinafter referred to as “addition reactive group”) is introduced into both terminals thereof can also be used. That is, a method is used in which a soluble polyimide is dissolved in a solvent to form a liquid, adjusted to an appropriate viscosity, applied to an amorphous metal ribbon, and heated to evaporate the solvent to form a heat-resistant resin.
Next, a process for producing a magnetic core of an electric motor using the laminate according to the present invention will be described. However, the manufacturing process is up to the winding process. The steps in the present invention are not limited to the order described below, and the following steps can be combined.
[0023]
(Lamination integrated processing process)
The production method of laminating the amorphous metal ribbon using a magnetic base material to which a high heat-resistant thermoplastic resin or a precursor of the high heat-resistant thermoplastic resin is previously applied will be described in detail.
[0024]
The manufacturing process of the laminated body of the magnetic base material in which the high heat-resistant thermoplastic resin is provided to the amorphous metal ribbon may be performed by a multi-layer coating method or by pressing a single or multi-layer coated base material, for example, hot pressing or heat. They can be laminated by a roll or the like. The temperature at the time of pressurization differs depending on the type of heat-resistant resin, but it is generally preferable to laminate and press at a temperature near the softening or melting temperature above the glass transition temperature (Tg) of the cured product.
[0025]
In the production of the laminated body of the amorphous metal ribbon, the laminated structure can be freely designed by laminating and bonding by a multi-layer coating method or a hot press, a hot roll, a high frequency welding or the like.
[0026]
The amorphous metal ribbon laminate of the present invention is obtained by stacking amorphous metal ribbons, impregnating a thermoplastic, a heat-resistant resin or a thermoplastic, a precursor of a heat-resistant resin to form a resin by resinification. There is a method of manufacturing, preferably, using a magnetic base material in which a thermoplastic, heat-resistant resin or thermoplastic, a precursor of a heat-resistant resin is previously applied to an amorphous metal ribbon, and the base material is laminated and bonded. It is desirable to use a method of producing a laminate by using the method.
[0027]
(Shaping process)
When shaping the magnetic core for an electric motor of the present invention, a method of precision cutting such as press punching, discharge wire cutting, laser cutting, or the like can be applied, but is not limited thereto. Among these methods, press punching is preferable because the processing unit price is low during mass production. The shaping can be performed with only one amorphous metal ribbon, and it is also possible to simultaneously shape a plurality of laminated bodies after lamination and integration. In order to reduce the processing unit price, it is desirable to simultaneously shape a plurality of sheets.
[0028]
(Bending process)
In the magnetic laminate of the present invention, the thermoplastic resin is used between the layers of the amorphous metal ribbon, so that the thermoplastic resin is heated until fluidity is generated, and the amorphous metal ribbons constituting the magnetic laminate are interconnected. The magnetic laminate can be bent and deformed. In this state, the desired shape can be maintained by press-molding the thermoplastic resin into a desired shape and then cooling it until the fluidity of the thermoplastic resin is lost. By using this method, it is also possible to process into a bent shape for a winding guide to be applied to a thin motor or the like.
[0029]
(Heat treatment process)
This is a heat treatment performed to improve the magnetic properties of the amorphous metal ribbon of the present invention. The heat treatment temperature of the amorphous metal ribbon varies depending on the composition of the amorphous metal ribbon and the target magnetic properties, but is usually performed in an inert gas atmosphere or in a vacuum to obtain good magnetic properties. The temperature to be improved is generally from 300 to 500 ° C, preferably from 350 to 450 ° C.
[0030]
(Winding process)
The magnetic core for a motor of the present invention can be wound in a concentrated winding or distributed winding manner, for example, when a coated copper wire is wound around a stator-core shaped coating. After further winding the coated copper wire, it is necessary to crawl the lead wire of the coated copper wire along the circular stator-core. At this time, the stator-core has a winding serving as a projection for determining the position of the coated copper wire. With the guide, it is possible to prevent the covered copper wire from protruding, and it is possible to stably manufacture a stator-core winding.
[0031]
The magnetic laminate for a magnetic substrate motor of the present invention can be manufactured from a combination of the above steps. Representative combinations of each step are shown below.
Pattern 1:
(Resin application step) → (Lamination integrated processing step) → (Shape processing step) → (Bending processing step) → (Heat treatment step) → (Winding step)
Pattern 2:
(Resin application step) → (Shape processing step) → (Lamination integrated processing step) → (Bending processing step) → (Heat treatment step) → (Winding step)
In the pattern 1 step, a plurality of magnetic base materials obtained by applying a resin to an amorphous metal are stacked, laminated and integrated by a method such as hot pressing, to form a flat plate. In order to further form the motor core shape by press punching, etc., heat it to a temperature equal to or higher than the glass transition temperature of the resin, apply a winding guide, etc. by bending with a press, and further develop the magnetic characteristics of the amorphous metal Heat treatment. Finally, winding is applied. Since a plurality of patterns 1 can be pressed at a time, the cost reduction effect is remarkable and this is the most suitable processing step for mass production. When this step is performed using a magnetic laminate using a thermosetting resin, the resin hardens at the time of lamination and integration. Can not.
[0032]
In the pattern 2 process, a magnetic base material obtained by applying a resin to an amorphous metal is processed one by one into a motor core shape by press punching or the like, and then a plurality of the substrates are stacked and integrated by a method such as hot pressing. Into a motor core plate. Further, after heating to a temperature higher than the glass transition temperature of the resin, a winding guide or the like is applied by bending. The lamination integration processing and the bending processing can be performed simultaneously with the same mold. Further, a heat treatment for expressing the magnetic properties of the amorphous metal is performed. Finally, winding is applied.
[0033]
【Example】
Hereinafter, examples of the present invention will be described.
[0034]
[Example 1] Amorphous metal having a composition of Fe ₇₈ Si ₉ B ₁₃ (at%) of Metglas: 2605TCA (trade name), a width of about 170 mm and a thickness of about 25 μm, manufactured by Honeywell Co., Ltd. A ribbon (FIG. 3-1) was used. A polyamic acid solution having a viscosity of about 0.3 Pa · s is applied to both surfaces of the ribbon, and the solvent is volatilized at 150 ° C., and then a polyimide resin is formed at 250 ° C. An amorphous metal ribbon provided with a heat-resistant thermoplastic resin (polyimide resin) (FIG. 3-2) was produced. Dissolved in dimethylacetamide solvent using 3,3'-diaminodiphenyl ether as diamine and polyamic acid as precursor of polyimide obtained from bis (3,4-dicarboxyphenyl) ether dianhydride as tetracarboxylic dianhydride Then, it was applied on the amorphous metal ribbon and heated on the amorphous metal ribbon. This resin satisfied all the characteristic values described in claims 2 and 3 of the present invention.
[0035]
Next, 50 magnetic substrates to which the resin was applied were stacked and laminated and integrated at 270 ° C. for 30 minutes by hot pressing to obtain a magnetic laminated plate.
[0036]
Further, a stator core having an outer diameter of 50 mm and an inner diameter of 40 mm was punched out by press punching at once to produce a motor stator having the shape shown in FIG. 2 from the 50 laminated magnetic laminates. The winding guide was set in a mold for bending, and after heating, when the temperature reached 270 ° C., bending was performed by press molding. Further heating was performed, and heat treatment was performed at 350 ° C. for 2 hours to develop magnetic properties. As a result, the thickness became 1.37 mm, and a very high space factor (91%), which was almost the same as the space factor (95%) of the conventional laminate made of silicon steel sheet material, was realized. However, the space factor used here is a value calculated by the equation defined by the following equation.
(Occupation ratio (%)) = (((thickness of amorphous metal ribbon) × (number of laminated layers)) / (thickness of laminated body after lamination)) * 100
Even after the heat treatment, the laminated body did not peel off or warp, and the space factor was maintained at 91%. In addition, a ring having a core size (outer diameter 50 mm, inner diameter 40 mm) according to JIS H7153 “Test method for high-frequency core loss of amorphous metal core” is cut out with scissors, and 50 sheets are laminated by the same process as the motor stator described above. A ring was manufactured, and the iron loss was measured from a BH hysteresis loop when an alternating magnetic field of 1 Hz [T] of 1000 Hz was applied. As a result, the iron loss was 8.5 [W / kg], which was lower than that of the silicon steel sheet used in the conventional motor by one-third to one-third. It was confirmed that the characteristics were realized.
[0037]
Furthermore, when the winding was applied to the manufactured stator core, the winding guide formed by bending enabled the lead wire of the winding to be easily and stably wired along the winding guide in a short time. .
[0038]
[Example 2] Amorphous metal having a composition of Fe ₇₈ Si ₉ B ₁₃ (at%) of Metglas: 2605TCA (trade name), about 170 mm in width and about 25 μm in thickness in an amorphous metal ribbon formed by Honeywell Co., Ltd. A ribbon (FIG. 3-1) was used. A polyamic acid solution having a viscosity of about 0.3 Pa · s is applied to both surfaces of the ribbon, and the solvent is volatilized at 150 ° C., and then a polyimide resin is formed at 250 ° C. An amorphous metal ribbon provided with a heat-resistant thermoplastic resin (polyimide resin) (FIG. 3-2) was produced. Dissolved in dimethylacetamide solvent using 3,3'-diaminodiphenyl ether as diamine and polyamic acid as precursor of polyimide obtained from bis (3,4-dicarboxyphenyl) ether dianhydride as tetracarboxylic dianhydride Then, it was applied on the amorphous metal ribbon and heated on the amorphous metal ribbon. This resin satisfied all the characteristic values described in claims 2 and 3 of the present invention.
[0039]
From this thin strip, in order to produce a motor stator having the shape shown in FIG. 2, 50 sheets were stamped out into a stator-core shape having an outer diameter of 50 mm and an inner diameter of 40 mm. By setting the mold in a bending mold and performing thermocompression bonding at 270 ° C. for 30 minutes, bending processing for a winding guide and lamination integration were performed at the same time to obtain a motor stator shown in FIG. Further, while being set in a mold that had been subjected to lamination integration and bending of a winding guide, heat treatment was performed at 350 ° C. for 2 hours to develop magnetic characteristics. As a result, the thickness became 1.37 mm, and a very high space factor (91%), which was almost the same as the space factor (95%) of the conventional laminate made of silicon steel sheet material, was realized. However, the space factor used here is a value calculated by the equation defined by the following equation.
[0040]
(Occupation ratio (%)) = (((thickness of amorphous metal ribbon) × (number of laminated layers)) / (thickness of laminated body after lamination)) * 100
Even after the heat treatment, the laminated body did not peel off or warp, and the space factor was maintained at 91%. In addition, a ring having a core size (outer diameter 50 mm, inner diameter 40 mm) according to JIS H7153 “Test method for high-frequency core loss of amorphous metal core” is cut out with scissors, and 50 sheets are laminated by the same process as the motor stator described above. A ring was prepared, and the iron loss was measured from a BH hysteresis loop when an alternating magnetic field of 1 Hz of 1000 Hz was applied. As a result, the iron loss was 8.5 [W / kg], which was lower than that of the silicon steel sheet used in the conventional motor by one-third to one-third. It was confirmed that the characteristics were realized.
[0041]
Furthermore, when the winding was applied to the manufactured stator core, the winding guide formed by bending enabled the lead wire of the winding to be easily and stably wired along the winding guide in a short time. .
[0042]
Comparative Example 1 A motor stator core was manufactured in the same manner as in Example 1. However, the difference is that the resin used is a high heat-resistant thermosetting resin (the same structure as Kapton manufactured by DuPont). The resin was thermoset at 280 ° C., laminated and integrated to form a magnetic laminate, and then stamped into a stator core shape for a motor. Further, it was set in a mold for bending processing for a winding guide, and heated to 300 ° C., but the fluidity of the resin could not be obtained, and this could not be performed at the time of shaping the winding guide. For this reason, there is no projection of the winding guide, the lead wire of the φ 0.3 mm copper wire used for the winding protrudes from the stator core, the position of the winding wire is not fixed at the time of winding, and during winding work Disconnection occurred, and stable winding was difficult.
[0043]
Comparative Example 2 A magnetic base and a motor stator core similar to those in Example 1 were produced. After the heat treatment, the winding guide by bending was not applied. Therefore, as shown in FIG. 5, resin winding guides (0.4 mm in thickness) were provided on both surfaces of the motor stator core. Therefore, the thickness of the winding guide made of the present resin is (0.4 × 2 mm) thicker, about 1 mm thicker than in Examples 1 and 2 for thinning, which is disadvantageous in thinning the motor.
[0044]
The above is summarized in the table below.
[0045]
[Table 1]

[0046]
【The invention's effect】
The present invention provides an electric motor or a generator including a rotor made of a magnetic material and a stator, wherein at least a part of the magnetic material of the rotor or the stator is constituted by a laminate made of an amorphous metal magnetic ribbon. The laminate made of the amorphous metal magnetic ribbon has thermoplasticity, and more preferably, the resin loses 1% by weight or less by thermal decomposition when subjected to a heat history of 300 ° C. for 2 hours under a nitrogen atmosphere. It has been found that the following excellent effects can be obtained by forming a magnetic laminate in which resin layers and amorphous metal magnetic ribbon layers are alternately laminated.
[0047]
1) Bending processability The magnetic laminate is heated and bent in a state in which the heat-resistant resin has fluidity, cooled until fluidity is lost, and the shape is maintained to obtain a desired bending shape. This makes it possible to form a winding guide and the like necessary for the thin motor core.
[0048]
2) Heat treatment for expressing the excellent magnetic properties of the amorphous metal is possible, that is, the resin is hardly thermally decomposed even at the heat treatment temperature of the amorphous metal ribbon (300 ° C. to 500 ° C.). Therefore, the adhesive strength of the resin and the appropriate elastic modulus are maintained, and the overall mechanical strength of the resin-coated amorphous metal ribbon is reduced under the compressive stress in the lamination integration during the heat treatment or after the heat treatment. Even at room temperature, the amorphous metal ribbon is less likely to crack, chip, and the like. As a result, it is possible to overcome the brittleness of the Fe-based amorphous metal ribbon and the Co-based amorphous metal ribbon after the heat treatment, and at the same time, to exhibit excellent magnetic properties. The realization of the core became possible.
[0049]
3) High mechanical strength In addition, since the amorphous metal ribbon is coated with a resin in close contact, the crack inside the amorphous metal ribbon is prevented from expanding. That is, it is possible to prevent the cracks in the amorphous metal ribbon from expanding due to the stress generated when the motor or the generator rotates, and to secure sufficient mechanical strength as a motor.
[0050]
4) Formability Since it has high mechanical strength, precision cutting methods such as press punching, discharge wire cutting, and laser cutting can be applied without crack expansion, cracking, etc., and shape design. The degree of freedom increases, and a magnetic circuit having an optimal shape can be realized.
[0051]
In particular, in the press punching processing of the necessary comb blade-shaped portion for winding the windings, the rotor and the stator are usually not coated with a heat-resistant resin, and are often cracked and chipped, and it is difficult to perform stable shape processing. However, those coated with a heat-resistant resin could be processed stably without cracking or chipping.
[0052]
5) When a resin having a high space factor thermoplasticity is used, the resin flows at the time of heating and pressurizing during lamination integration, the voids between layers of the laminate are reduced, and the space factor is greatly improved. Becomes possible. Improving the space factor of the rotor or the stator in the motor or the generator leads to downsizing of the device or higher output.
[Brief description of the drawings]
FIG. 1 is a view showing an example of a conventional winding guide made of silicon steel sheet. FIG. 2 is a view showing a shape of a magnetic core for an electric motor according to a first embodiment of the present invention.
FIG. 3 is a diagram showing a process of manufacturing a magnetic base material according to Example 1 of the present invention.
FIG. 4 is a view showing a bending process of a winding guide according to a first embodiment of the present invention; FIG. 5 is a view showing a stator core provided with a resin winding guide according to a second comparative example of the present invention;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Winding 12 Winding guide 13 Stator core 21 Stator core 31 Amorphous metal ribbon 32 Heat resistant resin 41 Bending processed winding guide 51 Winding 52 Resin winding guide 53 Stator core

Claims

In a motor or a generator provided with a rotor made of a magnetic material and a stator, at least a part of the magnetic material of the rotor or the stator is formed of a laminate made of an amorphous metal magnetic ribbon, An electric motor characterized in that a laminate made of a thin strip has a shape retaining property by bending.

2. The motor according to claim 1, wherein the magnetic material is formed by alternately laminating an amorphous metal magnetic ribbon layer and a thermoplastic resin layer.

3. The electric motor according to claim 1, wherein the thermoplastic resin has a weight loss rate of 1% by weight or less due to thermal decomposition when subjected to a thermal history of 300 [deg.] C. for one hour in a nitrogen atmosphere. Magnetic laminate for generator.

The electric motor according to claim 1, wherein the amorphous metal magnetic ribbon material is an Fe-based amorphous metal ribbon or a Co-based amorphous metal ribbon.