JP5005131B2

JP5005131B2 - Linear motor

Info

Publication number: JP5005131B2
Application number: JP2001049625A
Authority: JP
Inventors: 毅森山; 哲村西; 修小久保; 郁馬成吉; 助広赤間; 照晃横山; 昇村上
Original assignee: Toshiba Machine Co Ltd
Current assignee: Shibaura Machine Co Ltd
Priority date: 2000-12-05
Filing date: 2001-02-26
Publication date: 2012-08-22
Anticipated expiration: 2021-02-26
Also published as: JP2002238240A

Description

【０００１】
【発明の属する技術分野】
本発明は、リニアモータに係り、特に、位相制御駆動リニアモータに関する。
【０００２】
【従来の技術】
従来より位相制御駆動リニアモータ、特に、三相同期駆動のリニアモータは、図７に示すように断面コ字状のサイドヨーク１０を備え、このサイドヨークの上片１２，下片１４の内面に、対向する磁石の極性が異なるようにかつ、それぞれ長手方向に隣接する磁石の極性が異なるようにＮ極，Ｓ極，Ｎ極，・・・・Ｓ極の配列で複数の永久磁石を有する第１、第２の永久磁石群５１，５２が設けられており、磁気回路が構成されている。この磁気回路内には、可動コイル３０が設けられており、可動コイル３０に、所定の方向に電流を印加することにより、図中Ａ方向に可動コイル３０を可動する構成となっている。
【０００３】
この可動コイル３０は、図９、図１０、図１１に示すように、補強板３２を挟んでそれ自身の上下面に、扁平形状のコイル部材３２Ａ，３２Ｂ，３２Ｃを設けた構成で、これらを各々所定間隔Ｋ１を空けて並列に配した構成となっている。また、三相交流で駆動するため、各相をＵ相、Ｗ相，Ｖ相とすれば、コイル部材３２Ａの３２Ａ１が［＋Ｕ］，３２Ａ２が［−Ｕ］，コイル部材３２Ｂの３２Ｂ１が［＋Ｗ］，３２Ｂ２が［−Ｗ］，コイル部材３２Ｃの３２Ｃ１が［＋Ｖ］，３２Ｃ２が［−Ｖ］相に対応するように、電流が印加されるようになっている。
また、この可動コイル３０は、図８に示すように長手方向の磁気回路の寸法Ｔがサイドヨーク１０の上下片１２，１４に設けられた永久磁石磁石群５１，５２の隣接する永久磁石の磁極が交互にＮ極，Ｓ極である、連続する４個の永久磁石を１単位とする長手方向の寸法Ｓと等しくなるように構成されている。
【０００４】
ここで、可動コイル３０の構造を、詳細に説明する。
【０００５】
前記可動コイル３０のコイル部材３２Ａ，３２Ｂ，３２Ｃは、ウエット巻きで作成されているが、サイドヨーク１０の上下片１２，１４と平行な扁平形状であるためにコイルに対する鉛直方向Ｙ及び捻れ剛性力が弱く、そのため、可動コイル３０は、補強板３２を介して組み立てられている。
この補強板３２には、予めコイルを補強板３２の上下面の所定の位置に固定するために、コイルの中空部、たとえば、３２Ａ３の形状と一致する凸部４２が設けられ、コイルの中空部３２Ａ３を凸部４２に挿通して固定するようになっている。また、補強板３２にはコイルを補強板３２上に実装した場合に、全体として可動コイル３０の水平面に凹凸が出来ないように、コイルの厚さ分Ｄ１と等しい深さＤ２の溝部４４が設けられている。
【０００６】
【発明が解決しようとする課題】
しかしながら、前記可動コイル３０には、下記のような不都合があった。
課題１、図９に示すようにコイル部材３２Ａ，３２Ｂ，３２Ｃの各中空部３２Ａ３、３２Ｂ３、３ＣＢ３（水平方向の幅Ｌ１＝８mm）が磁気回路に寄与せず、推力に寄与するのは、図中のコイル幅Ｆの部分だけで、無駄な部分が多く磁気の利用効率が悪い。
課題２、補強板３２の非磁性体部分が大きいために、磁石５１，５２からみた磁気抵抗が大きく磁場が弱められるという不都合が生じていた。
課題３、コイルに生じるＮ×Ｉ［通称：アンペアーターン］により、磁石５１，５２による磁場が乱れ、電流−推力のリニアリティが悪くなり制御性が悪化し、最悪の場合には振動が起きる事態を招くという可能性があった。
課題４、上記アンペアーターンにより、ヨーク１０内の磁気飽和を誘起しやすくなり、第１、第２の永久磁石群５１，５２による磁場が弱まる。また、渦電流が発生し、ヨークの温度上昇を招き、これにより永久磁石５０の温度特性により磁場が弱められる不都合が生じていた。
課題５、可動コイル３０のコイル部材３２Ａ，３２Ｂ，３２Ｃは、扁平形状であり、その厚さは２〜３ｍｍ程度のため、コイル部材３２Ａ，３２Ｂ，３２Ｃだけでは、磁気回路内における鉛直方向Ｙに対する剛性力が弱く、ねじれを生じるため、非磁性体で構成された補強板３２が必要であり、可動コイル３０の軽量化が難しい。
以上により、大推力でかつ、安定した正確な位置決め精度が必要な、精密機械における読み取りヘッドを実装した可動コイル３０等では、可動コイル３０を大型化し、大電流を流さなければ必要な推力を得られなかった。
本発明は、このような従来の難点を解決するためになされたもので、可動コイルの形状を鋭意研究し、位相制御駆動リニアモータにおいて、磁場の利用効率が高く、しかもヨークの発熱を抑制でき、可動コイルを小型化でき安定した推力を得ることが出来るリニアモータを提供することを目的とする。
【０００７】
【課題を解決するための手段】
本発明によれば、
ヨークと、可動コイルと、複数の永久磁石を有する第１の永久磁石群と、複数の永久磁石を有する第２の永久磁石群とを有する、リニアモータであって、
前記ヨークは、共通ヨークと、前記共通ヨークの一端に連続し前記共通ヨークと直交する第１のサイドヨークと、前記共通ヨークの他端に連続し前記共通ヨークと直交しかつ前記第１のサイドヨークと対向する第２のサイドヨークと、前記第１のサイドヨーク、前記共通ヨークおよび前記第２のサイドヨークとの間に規定される空洞部における、前記対向する第１および第２のサイドヨークの中間に位置するセンタヨークとを有し、
前記ヨークを構成する、前記共通ヨーク、前記第１および第２のサイドヨークおよび前記センタヨークは、前記可動コイルが移動する長手方向に前記可動コイルが移動する範囲に形成されており、
前記第１の永久磁石群は、前記第２のサイドヨークと対向する前記第１のサイドヨークの面に、前記長手方向に沿って配設された複数の永久磁石を有し、当該複数の永久磁石は隣接する永久磁石の磁極を異ならせて配設されており、
前記第２の永久磁石群は、前記第１のサイドヨークと対向する前記第２のサイドヨークの面に、前記長手方向に沿って配設された複数の永久磁石を有し、当該複数の永久磁石は隣接する永久磁石の磁極を異ならせて配設されており、かつ、前記対向する第１の永久磁石群の複数の永久磁石と長手方向の配設位置が同じで、対向する永久磁石同士の磁極が同じであり、
前記可動コイルは、３個の第１のコイル部材からなる第１のコイル組を有し、
前記３個の第１のコイル部材は中心に前記センタヨークに挿通する空洞を有し、
前記３個の第１のコイル部材の各々の長手方向の長さは、前記各永久磁石の長手方向の長さの２／３であり、
前記３個の第１のコイル部材は、前記空洞の周囲に、かつ、前記長手方向に沿って前記各永久磁石の長手方向の長さの２／３の間隔を隔てて配設され、
前記３個の第１のコイル部材は前記センターヨークの長手方向と直交する向きで同じ方向に巻回され、その断面形状が前記第１および第２のサイドヨークに対向する面が平坦であり矩形の外形をしており、
前記長手方向に配設された前記３個の第１のコイル部材を有する第１のコイル組の長手方向の長さが、前記対向して配設された前記第１および第２の永久磁石群それぞれの長手方向に配列された連続する４個の永久磁石の長手方向の長さに等しくなるように、前記第１のコイル組および前記複数の永久磁石が構成されており、
前記３個の第１のコイル部材には、それぞれ位相差が１２０度の交流電流が印加される、リニアモータが提供される。
【０００８】
【発明の実施形態】
以下、本発明に係る、位相制御駆動リニアモータ、特に、三相同期駆動リニアモータの実施の一形態を図１乃至図４に基づいて説明する。
ここで、前述した図７乃至図１１に示した従来技術と同一の部材には、同一の符号を付すものとする。
図１において、本実施例に係る、リニアモータは、ヨーク１を備えている。このヨーク１は、断面が略Ｅ字状である。すなわち、ヨーク１は、共通ヨーク１１と、この共通ヨーク１１の両端に連続し、共通ヨーク１１と直交する上片（サイドヨーク）１２，下片（サイドヨーク）１３及びセンターヨーク１６を具備する構成となっている。共通ヨーク１１上片（サイドヨーク）１２および下片（サイドヨーク）１３は、断面がコ字状である。
サイドヨーク１２，１３の内面には、図１に示すように、対向する磁石の磁極が同一で、かつ、それぞれ長手方向に隣接する磁石の磁極が異なるように、Ｎ極，Ｓ極，Ｎ極・・・・・・Ｓ極の配列で、複数の永久磁石からなる第１および第２の永久磁石群５１、５２が設けられ、磁気回路が構成されている。
この磁気回路内には、センターヨーク１６をそれ自身の空洞部に挿通してなる可動コイル３が設けられており、可動子タイル３を構成する各コイル部材に所定の位相の電流を印加することにより、可動子タイル３が図中Ａ方向に可動する構成となっている。
可動コイル３は、具体的には、図２に示すように、接着剤等を塗布した導線を中央部に空洞５を設けた、中空形状に多層巻きした、通称、ウエット巻きしたコイル部材３Ａ１，３Ａ２，・・・・，３Ｃ２を６個を非磁性体の絶縁部材９、例えば、ガラスエポキシ樹脂や絶縁処理（硬質アルマイト処理）されたアルミ合金で接合して、一体化した構成となっている。
【０００９】
この可動コイル３は、図３に示すように、位相差１２０度の三相交流で同期駆動されるように構成するため、各相をＵ相、Ｗ相、Ｖ相とし、隣接するコイル部材３Ａ１が［＋Ｕ］，３Ａ２が［−Ｕ］，隣接するコイル部材３Ｂ１が［＋Ｗ］，３Ｂ２が［−Ｗ］，隣接するコイル部材３Ｃ１が［＋Ｖ］，３Ｃ２が［−Ｖ］相に対応するように、電流が印加されるようになっている。
【００１０】
＋Ｕ相，−Ｕ相は位相がπ（ラジアン）（１８０度）異なる。
【００１１】
同様に、＋Ｗ相，−Ｗ相及び＋Ｖ相，−Ｖ相も各々位相が１８０度異なるように電流が印加されるようになっている。
そして、可動コイル３０の長手方向の寸法Ｔがサイドヨーク１２，１４に設けられた磁石５１、５２のＮ極，Ｓ極の単位磁石４組分の寸法Ｓと等しくなるように構成されている。
【００１２】
ここで、本実施例の動作原理を説明する。
図５は、三相交流リニアモータの動作原理１であり、図６は、本発明に係る三相交流リニアモータの動作原理２を示す図面である。
図３に示すように、本発明に用いられるリニアモ−タは、ヨーク１の対向する上片（サイドヨーク）１２と下片（サイドヨーク）１３それぞれに長手方向に設けられた連続する４個の永久磁石６（たとえば、図５、永久磁石６−１〜６−４、および、永久磁石６−８〜６−１１）と、長手方向に設けられた連続する６個の中空コイル３（６個のコイル部材３Ａ１，３Ａ２，３Ｂ１，３Ｂ２，３Ｃ１，３Ｃ２）を動作単位として構成されている。
【００１３】
ここでは基本原理を説明するために図５に示すように４個の永久磁石６を永久磁石６−２〜６−５の４個および永久磁石６−８〜６−１１の４個と一体となって移動する、図３に図解した６個の中空コイルの一方、たとえば、コイル部材３Ａ１，３Ｂ１，３Ｃ１として示す、３個の中空移動コイル（コイル部材）を動作単位としている。
【００１４】
図５に示すとおり、永久磁石６−３から出力された磁束は、センターヨーク１６を経由して、永久磁石６−２、又は、永久磁石６−２及び永久磁石６−４に入力される。
また、永久磁石６−９から出力された磁束は、センターヨーク１６を経由して、永久磁石６−８又は、永久磁石６−８及び永久磁石６−１０に入力される。
【００１５】
同様にして、永久磁石６−５から出力された磁束は、センターヨーク１６を経由して、永久磁石６−４又は、永久磁石６−４及び永久磁石６−６に入力される。
また、永久磁石６−１１から出力された磁束は、センターヨーク１６を経由して、永久磁石６−１０又は、永久磁石６−１０又は、永久磁石６−１２に入力される。
【００１６】
永久磁石６−２及び永久磁石６−８の左側を起点として位置角（磁場の位相角）を設定する。位置角は、磁極方向に隣接する永久磁石毎にπ（ラジアン）進むものと定める。また、永久磁石６−２及び永久磁石６−８の左側を起点として右方向（Ｘ軸方向）へ一体となって移動する３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１（中空コイル）の移動する距離をｘと定める。
コイル部材３Ａ１が距離ｘだけＸ軸方向へ移動したときに鎖交する磁束数を
Ｂａ＝Ｂｍ・ｓｉｎ（ｘ） …（１式）
コイル部材３Ｂ１が距離ｘだけＸ軸方向へ移動したときに鎖交する磁束数を
Ｂｂ＝Ｂｍ・ｓｉｎ（ｘ−４π／３） …（２式）
コイル部材３Ｃ１が距離ｘだけＸ軸方向へ移動したときに鎖交する磁束数を
Ｂｃ＝Ｂｍ・ｓｉｎ（ｘ−８π／３）＝Ｂｍ・ｓｉｎ（ｘ−２π／３）
…（３式）
とおく。
ここでＢｍは永久磁石の最大磁束密度とし、各コイル部材の位置ズレを上記位置角で表す。
図３に示すコイル部材３Ａ１に三相交流の＋Ｕ相、コイル部材３Ｂ１に＋Ｗ、コイル部材３Ｃ１に＋Ｖがそれぞれ供給されている。
したがって、コイル部材３Ａ１に流れる電流は、
Ｉａ＝Ｉｍ・ｓｉｎ（ωｔ） …（４式）
コイル部材３Ｂ１に流れる電流は、
Ｉｂ＝Ｉｍ・ｓｉｎ（ωｔ−４π／３） …（５式）
コイル部材３Ｃ１に流れる電流は、
Ｉｃ＝Ｉｍ・ｓｉｎ（ωｔ−２π／３） …（６式）
となる。
以上求めた（１式）から（６式）より永久磁石６−１〜６−６の界磁磁束とコイル部材に流れる電流が鎖交することによって３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１に働く推力Ｆは次式で表される。
Ｆ＝Ｂａ・Ｉａ＋Ｂｂ・Ｉｂ＋Ｂｃ・Ｉｃ
＝Ｂｍ・Ｉｍ・｛ｓｉｎ（ｘ）・ｓｉｎ（ωｔ）
＋ｓｉｎ（ｘ−４π／３）・ｓｉｎ（ωｔ−４π／３）
＋ｓｉｎ（ｘ−２π／３）・ｓｉｎ（ωｔ−２π／３）｝
同期している場合、ωｔ＝ｘであるから
Ｆ＝Ｂｍ・Ｉｍ・｛ｓｉｎ² （ｘ）＋ｓｉｎ² （ｘ−４π／３）
＋ｓｉｎ² （ｘ−２π／３）｝
＝（３／２）・Ｂｍ・Ｉｍ−（１／２）・Ｂｍ・Ｉｍ・｛ｃｏｓ（２ｘ）
＋ｃｏｓ（２ｘ−８π／３）＋ｃｏｓ（２ｘ−４π／３）｝
＝（３／２）・Ｂｍ・Ｉｍ−（１／２）・Ｂｍ・Ｉｍ・｛ｃｏｓ（２ｘ）
＋ｃｏｓ（２ｘ−２π／３）＋ｃｏｓ（２ｘ−４π／３）｝
＝（３／２）・Ｂｍ・Ｉｍ・−（１／２）・Ｂm・Ｉm・｛ｃｏｓ（２ｘ）
＋［ｃｏｓ（２ｘ）・ｃｏｓ（２π／３）
＋ｓｉｎ（２ｘ）・ｓｉｎ（２π／３）］
＋［ｃｏｓ（２ｘ）・ｃｏｓ（４π／３）
＋ｓｉｎ（２ｘ）・ｓｉｎ（４π／３）］｝
＝（３／２）・Ｂｍ・Ｉｍ−（１／２）・Ｂｍ・Ｉｍ・｛ｃｏｓ（２ｘ）
−（１／２）・ｃｏｓ（２ｘ）＋（√３／２）・ｓｉｎ（２ｘ）
−（１／２）・ｃｏｓ（ｘ）−（√３／２）・ｓｉｎ（２ｘ）｝
＝（３／２）・Ｂｍ・Ｉｍ
…（７式）
以上、永久磁石６−１〜６−６の界磁磁束と３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１に働く推力Ｆについて説明した。
また、３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１には、永久磁石６−７〜６−１２の界磁磁束との鎖交によっても推力Ｆが同一方向に働くが、上述と同様の理論なので説明を省略する。
【００１７】
ここで、留意すべき点は以下の通りである。
すなわち、４個の永久磁石６−２〜６−５に対して３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１が一組となって動作する。これ以外の組み合わせでは、駆動電流の位相角とコイル部材の位置角が一致しないので推力リップルが大きくなる。
次に、本発明に係る三相同期リニアモータの動作原理を図６に示す基本原理２に基づいて詳細に説明する。
上述した基本原理１は、位置角にして２π／３の長さをもつ３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１がそれぞれお互いに位置角＝４π／３の間隔をおいて配置されていたのに対し、本実施例（基本原理２）では、その間隔の中に位置角にして２π／３の長さをもつ、３個のコイル部材３Ａ２，３Ｂ２，３Ｃ２が配置されている。
さらに、図３に示すように、コイル部材３Ａ１に＋Ｕ相、コイル部材３Ａ２に−Ｕ相、同様に、コイル部材３Ｂ１に＋Ｗ相、コイル部材３Ｂ２に−Ｗ相、コイル部材３Ａ３に＋Ｖ相、コイル部材３Ｂ３に−Ｖ相の電流が印加されるように接続されている。
【００１８】
本実施例の場合、同一コイル部材３Ａ１，３Ａ２，・・，３Ｃ２は同一方向巻きの同一コイル部材からなり、これらを巻き方向が同じになるように図３のように配列して、例えば隣接するコイル部材３Ａ１と３Ａ２の場合には、コイル部材３Ａ１の巻きはじめの端をＫＳ１，巻き終わりの端をＫＥ１，同様にコイル部材３Ａ２の巻き始めの端をＫＳ２，巻き終わりの端をＫＥ２とすれば、コイル部材３Ａ１，３Ａ２の接続は、ＫＥ１−ＫＥ２を接続するようになっている。
回路的には、ＫＳ１−ＫＥ１−ＫＥ２−ＫＳ２で電気回路が成立している。
これによって、三相交流のＵ相の場合、コイル部材３Ａ１に＋Ｕ相、コイル部材３Ａ２に−Ｕ相を印加したのと同様になる。以下、Ｗ相，Ｖ相も同様である。
ここで三相交流の＋Ｕ，−Ｕ相は正相とその逆相を意味しており、位相差π（１８０度）である。＋Ｗ，−Ｗ相及び＋Ｖ相，−Ｖ相も同様である。
かかる接続を採用することによりコイル部材３Ａ２，３Ｂ２，３Ｃ２に印加される駆動電流の位相はそれぞれ２π／３遅れる。一方、コイル部材３Ａ２，３Ｂ２，３Ｃ２は、コイル部材３Ａ１，３Ｂ１，３Ｃ１の長手方向において後ろに接続されるので、位置角もそれぞれ２π／３（ラジアン）遅れる。したがって，上記（７式）を満足する。その結果コイル部材３Ａ１，３Ｂ１，３Ｃ１に働く推力とコイル部材３Ａ２，３Ｂ２，３Ｃ２に働く推力は同一方向となる。
【００１９】
すなわち、本実施例のリニアモータは、上記基本原理１で説明した３個のコイル部材３Ａ１，３Ｂ１，３Ｃ１からなるリニアモータの可動コイルの容積を増加させることなく、２組の可動コイルを直列接続したのと等価となる。
【００２０】
この構成は、課題３，４を解決するために採用した構成で、主に、可動コイルに生じるＮ×Ｉ［通称：アンペアーターン］により、不要な方向の磁場を抑制し、磁気回路内の推力発生磁場の乱れを小さくすると共に、アンペアーターンによる、ヨーク１内に発生する渦電流を抑制して、ヨークの温度上昇を防ぎ、永久磁石群５１、５２を構成する複数の永久磁石の温度特性により磁場の低下を防ぐという効果がある。
【００２１】
つまり、コイル部材３Ａ１の駆動電流Ｉｍｓｉｎ（ωｔ）によって励起される磁束をＨＡ１とすると、コイル部材３Ａ２の駆動電流は、−Ｉｍ・ｓｉｎ（ωｔ）によって励起される磁束をＨＡ２となり磁束の向きが反転してうち消し合うことになる。
同様に、コイル部材３Ｂ１，３Ｂ２及び３Ｃ１と３Ｃ２に励起される磁束も同様の結果となり、ヨーク内に発生する渦電流の発生を抑制することができる。
【００２２】
尚、上記の説明では、４個の永久磁石６−２〜６−５に対して６個のコイル部材３Ａ１，３Ａ２，３Ｂ１，３Ｂ２，３Ｃ１，３Ｃ２を一組としたが、本発明はこれに限るものではない。
【００２３】
すなわち、上記（７式）を満足するのは、長手方向に連続する４個の永久磁石に対して長手方向に連続する６個のコイル部材が一組となる場合に限らない。（７式）を満足するためには、コイル部材に印加される駆動電流の位相角と、そのコイル部材の位置角が等しければよい。
【００２４】
つまり、移動方向（Ｘ方向、または、長手方向）に並ぶ永久磁石４n個（nは整数）を一組として、上記移動方向への位置角４π（ラジアン）を設定したときに、複数個のコイル部材の上記移動方向への長さが永久磁石４Ｎ個の長さに等しければよい。
【００２５】
但し、複数個のコイル部材の各々の位置角に相当する位相角の駆動電流を各々のコイル部材に印加する必要がある。
【００２６】
尚、この場合においても、複数個のコイル部材の数量を適宜設定することにより上記漏洩磁束を低減させることも可能になる。
ここで基本原理２の説明を終わる。
尚、各コイル部材３Ａ１，・・・・３Ｃ２は、それぞれ同一の巻数で、同一の仕様となっている。
【００２７】
隣接する各コイル部材３Ａ１，３Ａ２の接合寸法ｄは、小さい方が好ましいが、本実施例では、２mm程度となっている。
また、この可動コイル３は、多層巻きされ接着剤などの接合部材で矩形状に固められているため、従来例に比べ、鉛直方向Ｙに対する剛性力が強く、可動コイル３の変形が皆無である。
また、隣接する各コイル部材３Ａ１，３Ａ２，・・・・，３Ｃ２には、それぞれ逆位相の電流が印加され、かつ、非常に密に隣接して配列されているので、コイル部材３Ａ１，３Ａ２，・・・，３Ｃ２の各コイルのアンペアターン（Ｎ：巻数，Ｉ：電流）により発生する磁束を相互に打ち消し合うことができるので、ヨーク１内に発生する［鉄損］を限りなく［０］にすることができる。
このことは、ヨークの磁気飽和を抑え、磁場の変化をなくし、熱性能が向上することにつながり、永久磁石群５１、５２を構成する複数の永久磁石の磁束の温度変化による磁束の変化を抑え、安定した推力を得るという効果がある。
【００２８】
図４は、本実施例に係る、リニアモータの構成説明図で、３Ａは、可動コイル３に設けた部品部材である。また、可動コイル３には補強板を取り付けてもよい。
【００２９】
このようにすれば、可動コイル３の剛性がさらに大きくなる。
【００３０】
尚、本発明はこれに限らず、可動コイル３を構成するコイル部材３Ａ１〜３Ａ６と永久磁石群５１、５２の複数の永久磁石の関係を、長手方向に６（６×ｎ）個［ｎは整数］組配列し、その長手方向の寸法は、サイドヨーク１６に配設された複数の永久磁石の配列に注目した場合、長手方向に配設された複数の永久磁石の個数（４×ｎ）［ｎは整数］組と同じになる構成とすれば、可動コイル３を構成するコイル部材を水平方向にｎ組連結して駆動することも出来る。
このような構成のリニアモータは、より大きな推力を容易に得ることが出来る。
【００３１】
尚、本実施例では６個のコイル部材３Ａ１，３Ａ２，・・，３Ｃ２は同一方向巻きとして、＋Ｕ，−Ｕ，＋Ｗ，−Ｗ，＋Ｖ，−Ｖ相の電流を印加したが、隣接するコイル部材３Ａ１，３Ａ２，・・，３Ｃ２の巻き方向を相互に逆巻きにして配列すれば、＋Ｕ，＋Ｖ，＋Ｗ，＋Ｕ，＋Ｖ，＋Ｗ相の電流を印加しても駆動できる。但しこの場合には、隣接するコイル部材３Ａ１，３Ａ２，・・，３Ｃ２からの漏洩磁束をうち消す効果はない。
【００３２】
【発明の効果】
本発明は、以上のように構成されているので、位相制御駆動リニアモータにおいて、磁場の利用効率が高く、しかもヨークの発熱を抑制でき、可動コイルを小型化にでき安定した推力を得ることが出来るリニアモータを提供することができる。
【図面の簡単な説明】
【図１】本発明の位相制御駆動リニアモータ概要を示す説明図。
【図２】本発明の可動コイルの構成説明図。
【図３】本発明の磁気回路の説明図。
【図４】本発明のヨークと可動コイルの関係を示す説明図。
【図５】本発明にかかるリニアモータの基本動作原理１を示す説明図。
【図６】本発明にかかるリニアモータの基本動作原理２を示す説明図。
【図７】従来の位相制御駆動リニアモータ概要を示す説明図。
【図８】従来の磁気回路の説明図。
【図９】従来の可動コイルの平面説明図。
【図１０】従来のヨークと可動コイルの関係を示す説明図。
【図１１】従来の可動コイルの構成を示す組立説明図。
１…ヨーク、３…可動コイル、５…空洞、１２，１４…サイドヨーク、１６…センターヨーク、３Ａ１，３Ａ２，３Ｂ１，３Ｂ２，３Ｃ１，３Ｃ２…コイル部材、５１、５２…永久磁石群[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear motor, and more particularly to a phase control drive linear motor.
[0002]
[Prior art]
Phase control drive linear motors than the conventional, in particular, a linear motor of three-phase synchronous drive has a U-shaped cross section of the side yoke 10 as shown in FIG. 7, upper piece 12 of the side yoke, the inner surface of the lower piece 14 , Having a plurality of permanent magnets in an arrangement of N poles, S poles, N poles,... S poles so that the polarities of the opposing magnets are different and the polarities of the magnets adjacent in the longitudinal direction are different . First and second permanent magnet groups 51 and 52 are provided to form a magnetic circuit. The magnetic circuit has a movable coil 30 is provided to the moving coil 30, by applying a current in a predetermined direction, it has a configuration that moves the movable coil 30 in the figure A direction.
[0003]
As shown in FIGS. 9, 10, and 11, the movable coil 30 has a configuration in which flat coil members 32 </ b> A, 32 </ b> B, and 32 </ b> C are provided on the upper and lower surfaces of the reinforcing plate 32. Each is arranged in parallel at a predetermined interval K1. Since each phase is U phase, W phase, and V phase for driving with three-phase AC, 32A1 of the coil member 32A is [+ U], 32A2 is [−U], and 32B1 of the coil member 32B is [+ W]. ], 32B2 is [-W], 32C1 coil member 32C is [+ V], so 32C2 corresponds to [-V] phase, so that the current is applied.
Further, as shown in FIG. 8, the movable coil 30 has a magnetic circuit dimension T in the longitudinal direction and the magnetic poles of the permanent magnets adjacent to the permanent magnet groups 51 and 52 provided on the upper and lower pieces 12 and 14 of the side yoke 10. Are configured to be equal to the longitudinal dimension S with four continuous permanent magnets as one unit .
[0004]
Here, the structure of the movable coil 30 will be described in detail.
[0005]
The coil members 32A, 32B, and 32C of the movable coil 30 are formed by wet winding, but have a flat shape parallel to the upper and lower pieces 12 and 14 of the side yoke 10, and therefore, the vertical direction Y and torsional rigidity force with respect to the coil. Therefore, the movable coil 30 is assembled via the reinforcing plate 32.
The reinforcing plate 32 is provided with a hollow portion of the coil , for example, a convex portion 42 corresponding to the shape of 32A3 , in order to fix the coil in a predetermined position on the upper and lower surfaces of the reinforcing plate 32 in advance. 32A3 is inserted into the convex portion 42 and fixed. Further, when the coil is mounted on the reinforcing plate 32, the reinforcing plate 32 is provided with a groove portion 44 having a depth D2 equal to the coil thickness D1 so that the horizontal surface of the movable coil 30 cannot be uneven as a whole. It has been.
[0006]
[Problems to be solved by the invention]
However, the movable coil 30 has the following disadvantages.
Problem 1, as shown in FIG. 9, the hollow portions 32A3 , 32B3, 3CB3 (horizontal width L1 = 8 mm) of the coil members 32A, 32B, 32C do not contribute to the magnetic circuit, but contribute to the thrust. There are many useless parts only in the coil width F part in the inside, and the utilization efficiency of magnetism is poor.
Problem 2, since the non-magnetic part of the reinforcing plate 32 is large, there is a disadvantage that the magnetic resistance viewed from the magnets 51 and 52 is large and the magnetic field is weakened.
Problem 3, N × I [common name: ampere-turn] generated in the coil disturbs the magnetic field generated by the magnets 51 and 52, deteriorates the linearity of current-thrust, deteriorates controllability, and in the worst case, causes vibration. there is a possibility of causing.
Problem 4, the ampere turn makes it easier to induce magnetic saturation in the yoke 10, and the magnetic fields generated by the first and second permanent magnet groups 51 and 52 are weakened. In addition, an eddy current is generated, resulting in a temperature rise of the yoke, which causes a disadvantage that the magnetic field is weakened by the temperature characteristics of the permanent magnet 50.
Problem 5, the coil members 32A, 32B, 32C of the movable coil 30 are flat and have a thickness of about 2 to 3 mm. Therefore, only the coil members 32A, 32B, 32C are in the vertical direction Y in the magnetic circuit. Since the rigidity is weak and twisting occurs, the reinforcing plate 32 made of a non-magnetic material is necessary, and it is difficult to reduce the weight of the movable coil 30.
As described above, in the movable coil 30 and the like mounted with a read head in a precision machine that requires a large thrust and a stable and accurate positioning accuracy, the movable coil 30 is enlarged, and a necessary thrust can be obtained unless a large current flows. I couldn't.
The present invention has been made to solve such a conventional problem, and has intensively studied the shape of the moving coil, and in the phase control drive linear motor, the use efficiency of the magnetic field is high, and the heat generation of the yoke can be suppressed. An object of the present invention is to provide a linear motor capable of reducing the size of the moving coil and obtaining a stable thrust.
[0007]
[Means for Solving the Problems]
According to the present invention,
A linear motor having a yoke, a movable coil , a first permanent magnet group having a plurality of permanent magnets, and a second permanent magnet group having a plurality of permanent magnets,
The yoke includes a common yoke, a first side yoke that is continuous with one end of the common yoke and orthogonal to the common yoke, a continuous side of the other end of the common yoke, orthogonal to the common yoke, and the first side yoke. The opposing first and second side yokes in a cavity defined between the second side yoke opposing the yoke, and the first side yoke, the common yoke , and the second side yoke. And a center yoke located in the middle of
Constituting the yoke, the common yoke, said first and second side yoke and the center yoke, the movable coil in the longitudinal direction of the moving coil is moved are formed in a range to move,
The first permanent magnet group has a plurality of permanent magnets disposed along the longitudinal direction on the surface of the first side yoke facing the second side yoke, and the plurality of permanent magnets. The magnet is arranged with different magnetic poles of adjacent permanent magnets,
The second permanent magnet group includes a plurality of permanent magnets arranged along the longitudinal direction on the surface of the second side yoke facing the first side yoke, and the plurality of permanent magnets. The magnets are arranged such that the magnetic poles of adjacent permanent magnets are different from each other, and the arrangement positions in the longitudinal direction are the same as those of the plurality of permanent magnets of the opposed first permanent magnet group. Magnetic poles are the same,
The movable coil has a first coil set composed of three first coil members,
The three first coil members have a cavity inserted through the center yoke at the center,
The longitudinal length of each of the three first coil members is 2/3 of the longitudinal length of each permanent magnet,
The three first coil members are arranged around the cavity and at intervals of 2/3 of the longitudinal length of each permanent magnet along the longitudinal direction .
The three first coil members are wound in the same direction in a direction perpendicular to the longitudinal direction of the center yoke, and the cross-sectional shape is flat with the surfaces facing the first and second side yokes being flat. It has a profile,
The longitudinal first coil pair of the longitudinal length having a direction disposed the previous SL three first coil member, said opposing said disposed in the first and second permanent magnets The first coil set and the plurality of permanent magnets are configured to be equal to the length in the longitudinal direction of four continuous permanent magnets arranged in the longitudinal direction of each group,
The front Symbol three first coil member, the phase difference each alternating current of 120 degrees is applied, the linear motor is provided.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a phase control drive linear motor, particularly a three-phase synchronous drive linear motor, according to the present invention will be described with reference to FIGS.
Here, the same members as those in the prior art shown in FIGS. 7 to 11 are denoted by the same reference numerals.
In Figure 1, according to the present embodiment, the linear motor includes a yaw click 1. The yoke 1 has a substantially E-shaped cross section. That is, the yoke 1 includes a common yoke 11, an upper piece (side yoke) 12, a lower piece (side yoke) 13, and a center yoke 16 that are continuous with both ends of the common yoke 11 and are orthogonal to the common yoke 11. It has become. The upper piece (side yoke) 12 and the lower piece (side yoke) 13 of the common yoke 11 have a U-shaped cross section.
As shown in FIG. 1, N poles, S poles, and N poles are provided on the inner surfaces of the side yokes 12 and 13 so that the magnetic poles of the opposing magnets are the same and the magnetic poles of the magnets adjacent in the longitudinal direction are different. ... A first and second permanent magnet group 51, 52 composed of a plurality of permanent magnets is provided in an S pole arrangement, and a magnetic circuit is configured.
In this magnetic circuit, there is provided a movable coil 3 formed by inserting the center yoke 16 through its own cavity, and a current having a predetermined phase is applied to each coil member constituting the movable element tile 3. Thus, the movable element tile 3 is configured to move in the direction A in the drawing.
Specifically, as shown in FIG. 2, the movable coil 3 is a coil member 3A1, commonly known as a wet coil, in which a conductive wire coated with an adhesive or the like is provided with a hollow 5 in the center, and is wound in a multilayer shape in a hollow shape. 3A2,..., 3C2 are joined together by a non-magnetic insulating member 9, for example, a glass epoxy resin or an aluminum alloy subjected to insulation treatment (hard alumite treatment). .
[0009]
As shown in FIG. 3, the movable coil 3 is configured to be synchronously driven by a three-phase alternating current with a phase difference of 120 degrees, so that each phase is a U phase, a W phase, and a V phase, and adjacent coil members 3A1. Is [+ U], 3A2 is [−U], adjacent coil member 3B1 is [+ W], 3B2 is [−W], adjacent coil member 3C1 is [+ V], and 3C2 is [−V]. In addition, a current is applied .
[0010]
The + U phase and the -U phase are different in phase by π (radians) (180 degrees).
[0011]
Similarly, current is applied so that the phases of the + W phase, the −W phase, the + V phase, and the −V phase are different from each other by 180 degrees.
The longitudinal dimension T of the movable coil 30 is configured to be equal to the dimension S of four sets of unit magnets of N and S poles of the magnets 51 and 52 provided on the side yokes 12 and 14.
[0012]
Here, the operation principle of the present embodiment will be described.
FIG. 5 shows an operation principle 1 of a three-phase AC linear motor, and FIG. 6 shows an operation principle 2 of the three-phase AC linear motor according to the present invention.
As shown in FIG. 3, the linear motor used in the present invention has four continuous motors provided in the longitudinal direction on the upper piece (side yoke) 12 and the lower piece (side yoke) 13 facing the yoke 1 respectively . Permanent magnet 6 (for example, FIG. 5, permanent magnets 6-1 to 6-4 and permanent magnets 6-8 to 6-11) and six continuous hollow coils 3 (six pieces ) provided in the longitudinal direction Coil members 3A1, 3A2, 3B1, 3B2, 3C1, 3C2) .
[0013]
Here and four integral four and permanent magnets 6-8～6-11 permanent magnet 6-2～6-5 the four permanent magnets 6 as shown in FIG. 5 to explain the basic principle One of the six hollow coils illustrated in FIG. 3, for example, three hollow moving coils (coil members) shown as coil members 3A1, 3B1, and 3C1, is used as an operation unit.
[0014]
As shown in FIG. 5, the magnetic flux output from the permanent magnet 6-3 via the center yoke 16, the permanent magnets 6-2, or, is input to the permanent magnet 6-2 and the permanent magnets 6-4.
The magnetic flux output from the permanent magnet 6-9 is input to the permanent magnet 6-8 or the permanent magnet 6-8 and the permanent magnet 6-10 via the center yoke 16 .
[0015]
Similarly, the magnetic flux output from the permanent magnet 6-5 is input to the permanent magnet 6-4 or the permanent magnet 6-4 and the permanent magnet 6-6 via the center yoke 16 .
The magnetic flux output from the permanent magnet 6-11 is input to the permanent magnet 6-10, the permanent magnet 6-10, or the permanent magnet 6-12 via the center yoke 16 .
[0016]
The position angle (magnetic field phase angle) is set starting from the left side of the permanent magnet 6-2 and the permanent magnet 6-8. The position angle is determined to advance by π (radian) for each permanent magnet adjacent in the magnetic pole direction. Also, the movement of the three coil member to move integrally the left permanent magnets 6-2 and the permanent magnets 6-8 rightward (X-axis direction) starting 3A1,3B1,3C1 (hollow coil) The distance is defined as x.
Ba = Bm · sin (x) (Expression 1) The number of magnetic fluxes linked when the coil member 3A1 moves in the X-axis direction by the distance x.
The number of magnetic fluxes interlinked when the coil member 3B1 moves in the X-axis direction by the distance x is expressed as follows: Bb = Bm · sin (x−4π / 3) (Expression 2)
The number of magnetic fluxes interlinked when the coil member 3C1 moves in the X-axis direction by the distance x is Bc = Bm · sin (x−8π / 3) = Bm · sin (x−2π / 3)
... (3 formulas)
far.
Here, Bm is the maximum magnetic flux density of the permanent magnet, and the positional deviation of each coil member is represented by the position angle.
Coil member 3 A1 in the three-phase alternating current of + U phase shown in FIG. 3, the coil member 3B1 + W, + V to the coil member 3C1 is supplied.
Therefore, the current flowing through the coil member 3A1 is
Ia = Im · sin (ωt) (Expression 4)
The current flowing through the coil member 3B1 is
Ib = Im · sin (ωt−4π / 3) (Expression 5)
The current flowing through the coil member 3C1 is
Ic = Im · sin (ωt−2π / 3) (Expression 6)
It becomes.
Above obtained (1 type) (6 type) from flowing to the field magnetic flux and the coil member of the permanent magnet 6-1 to 6-6 current three by interlinked coil member 3 A1,3B1,3C1 The thrust F acting on is expressed by the following equation.
F = Ba · Ia + Bb · Ib + Bc · Ic
= Bm · Im · {sin (x) · sin (ωt)
+ Sin (x-4π / 3) · sin (ωt-4π / 3)
+ Sin (x-2π / 3) · sin (ωt-2π / 3)}
If synchronized, since it is ωt = x F = Bm · Im · {sin 2 (x) + sin 2 (x-4π / 3)
+ Sin ² (x-2π / 3)}
= (3/2) .Bm.Im- (1/2) .Bm.Im. {Cos (2x)
+ Cos (2x-8π / 3) + cos (2x-4π / 3)}
= (3/2) .Bm.Im- (1/2) .Bm.Im. {Cos (2x)
+ Cos (2x-2π / 3) + cos (2x-4π / 3)}
= (3/2) .Bm.Im .- (1/2) .Bm.Im. {Cos (2x)
+ [Cos (2x) · cos (2π / 3)
+ Sin (2x) · sin (2π / 3)]
+ [Cos (2x) · cos (4π / 3)
+ Sin (2x) · sin (4π / 3)]}
= (3/2) .Bm.Im- (1/2) .Bm.Im. {Cos (2x)
-(1/2) .cos (2x) + (√3 / 2) .sin (2x)
-(1/2) .cos (x)-(√3 / 2) .sin (2x)}
= (3/2) · Bm · Im
... (7 formulas)
The field magnetic flux of the permanent magnets 6-1 to 6-6 and the thrust F acting on the three coil members 3A1, 3B1, 3C1 have been described above.
Further, the thrust F acts on the three coil members 3A1, 3B1, and 3C1 in the same direction by the linkage with the field magnetic flux of the permanent magnets 6-7 to 6-12. Is omitted.
[0017]
Here, the points to be noted are as follows.
That is, the three coil members 3A1, 3B1, and 3C1 operate as a set with respect to the four permanent magnets 6-2 to 6-5. In other combinations, the thrust ripple is increased because the phase angle of the drive current and the position angle of the coil member do not match.
Next, the operation principle of the three-phase synchronous linear motor according to the present invention will be described in detail based on the basic principle 2 shown in FIG.
In the basic principle 1 described above, the three coil members 3A1, 3B1, and 3C1 each having a position angle of 2π / 3 are arranged at a position angle = 4π / 3 from each other. On the other hand, in this embodiment (basic principle 2), three coil members 3A2, 3B2, and 3C2 having a position angle of 2π / 3 in the interval are arranged.
Furthermore, as shown in FIG. 3, the coil member 3A1 has a + U phase, the coil member 3A2 has a -U phase, similarly, the coil member 3B1 has a + W phase, the coil member 3B2 has a -W phase, and the coil member 3A3 has a + V phase. The member 3B3 is connected so that a -V phase current is applied .
[0018]
In the case of this embodiment, the same coil members 3A1, 3A2,..., 3C2 are made of the same coil members wound in the same direction, and are arranged as shown in FIG. In the case of the coil members 3A1 and 3A2, if the winding start end of the coil member 3A1 is KS1, the winding end end is KE1, similarly the winding start end of the coil member 3A2 is KS2, and the winding end end is KE2. The coil members 3A1 and 3A2 are connected to KE1-KE2.
In terms of circuit, an electric circuit is formed by KS1-KE1-KE2-KS2.
As a result, in the case of the three-phase alternating current U phase, it is the same as the + U phase applied to the coil member 3A1 and the -U phase applied to the coil member 3A2. Hereinafter, the same applies to the W phase and the V phase.
Here, the + U and -U phases of the three-phase alternating current mean the positive phase and the opposite phase, and are the phase difference π (180 degrees) . The same applies to the + W, −W phase, + V phase, and −V phase.
Phase of the drive current applied to the coil member 3A2,3B2,3C2 By employing such a connection, each 2 [pi / 3 delayed. On the other hand, the coil member 3A2,3B2,3C2 Since connected behind in the longitudinal direction of the coil member 3A1,3B1,3C1, respectively 2 [pi / 3 (rad) behind the position angle. Therefore, the above (Expression 7) is satisfied. As a result, the thrust acting on the coil members 3A1, 3B1, 3C1 and the thrust acting on the coil members 3A2, 3B2, 3C2 are in the same direction.
[0019]
That is, the linear motor of the present embodiment has two sets of movable coils connected in series without increasing the volume of the movable coil of the linear motor composed of the three coil members 3A1, 3B1, and 3C1 described in the basic principle 1 above. It is equivalent to
[0020]
This configuration is adopted to solve the problems 3 and 4, and mainly suppresses the magnetic field in the unnecessary direction by N × I [common name: ampere-turn] generated in the moving coil, and thrust in the magnetic circuit The turbulence of the generated magnetic field is reduced, the eddy current generated in the yoke 1 due to the ampere turn is suppressed, the temperature of the yoke is prevented from rising, and the temperature characteristics of the plurality of permanent magnets constituting the permanent magnet groups 51 and 52 are reduced. This has the effect of preventing the magnetic field from being lowered.
[0021]
That is, when the magnetic flux excited by the drive current Imsin (.omega.t) of the coil member 3A1 and HA1, the driving current of the coil member 3A2 is, - Im · sin (ωt) magnetic flux HA2 next magnetic flux orientation excited by the inversion Then they will be erased.
Similarly, the magnetic flux excited in the coil member 3B1,3B2 and 3C1 and 3C2 becomes the same result, it is possible to suppress the generation of eddy currents generated in the yoke.
[0022]
In the above description, six coil members 3A1, 3A2, 3B1, 3B2, 3C1, and 3C2 are set as one set for the four permanent magnets 6-2 to 6-5. It is not limited.
[0023]
That is, satisfying the above (Formula 7) is not limited to the case where the six coil members continuous in the longitudinal direction form a set with respect to the four permanent magnets continuous in the longitudinal direction . In order to satisfy (Expression 7), it is only necessary that the phase angle of the drive current applied to the coil member is equal to the position angle of the coil member.
[0024]
In other words, when a position angle 4π (radian) in the moving direction is set with a set of 4n permanent magnets (n is an integer) aligned in the moving direction (X direction or longitudinal direction ), a plurality of coils The length of the member in the moving direction may be equal to the length of 4N permanent magnets.
[0025]
However, it is necessary to apply a drive current having a phase angle corresponding to the position angle of each of the plurality of coil members to each coil member.
[0026]
In this case as well, the leakage magnetic flux can be reduced by appropriately setting the number of the plurality of coil members.
Here, the explanation of the basic principle 2 ends.
Each coil member 3A1,... 3C2 has the same number of turns and the same specifications.
[0027]
A smaller joint dimension d between the adjacent coil members 3A1 and 3A2 is preferable, but in this embodiment, it is about 2 mm.
In addition, since the movable coil 3 is wound in multiple layers and is fixed in a rectangular shape by a bonding member such as an adhesive, the movable coil 3 has higher rigidity in the vertical direction Y than the conventional example, and there is no deformation of the movable coil 3. .
Further, the adjacent coil members 3A1, 3A2,..., 3C2 are respectively applied with currents of opposite phases and are arranged very closely adjacent to each other, so that the coil members 3A1, 3A2, ..., the magnetic fluxes generated by the ampere turns (N: number of turns, I: current) of each coil of 3C2 can be canceled each other, so that [iron loss] generated in the yoke 1 is unlimited [0] Can be.
This suppresses the magnetic saturation of the yoke, eliminates the change of the magnetic field, improves the thermal performance, and suppresses the change of the magnetic flux due to the temperature change of the magnetic flux of the plurality of permanent magnets constituting the permanent magnet groups 51 and 52. There is an effect of obtaining a stable thrust.
[0028]
4, according to the present embodiment, a configuration explanatory view of a linear motor, 3A is a component member provided on the variable dynamic coil 3. It may also be fitted with a reinforcement plate to the movable coil 3.
[0029]
In this way, the rigidity of the moving coil 3 is further increased.
[0030]
The present invention is not limited thereto, a plurality of permanent magnets of relationship coil member 3A1~3A6 and the permanent magnet group 51, 52 constituting the movable coil 3, in the longitudinal direction 6 (6 × n) pieces [n is Integer] The number of the permanent magnets arranged in the longitudinal direction is 4 × n when the arrangement of the plurality of permanent magnets is focused on the arrangement of the permanent magnets arranged in the side yoke 16. If the configuration is the same as the [n is an integer] set, the coil members constituting the movable coil 3 can be connected in the horizontal direction and driven.
The linear motor having such a configuration can easily obtain a larger thrust.
[0031]
In this embodiment, the six coil members 3A1, 3A2,..., 3C2 are wound in the same direction, and + U, −U, + W, −W, + V, and −V phase currents are applied. If the winding directions of the members 3A1, 3A2,..., 3C2 are reversed, they can be driven even when + U, + V, + W, + U, + V, and + W phase currents are applied . However, in this case, there is no effect of eliminating the leakage magnetic flux from the adjacent coil members 3A1, 3A2,.
[0032]
【Effect of the invention】
Since the present invention is configured as described above, in the phase control drive linear motor, the use efficiency of the magnetic field is high, the heat generation of the yoke can be suppressed , the movable coil can be reduced in size, and a stable thrust can be obtained. it is possible to provide a linear motor that can be.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an outline of a phase control drive linear motor of the present invention.
FIG. 2 is a diagram illustrating the configuration of a moving coil according to the present invention.
FIG. 3 is an explanatory diagram of a magnetic circuit of the present invention.
FIG. 4 is an explanatory diagram showing a relationship between a yoke and a movable coil according to the present invention.
FIG. 5 is an explanatory diagram showing a basic operating principle 1 of a linear motor according to the present invention.
FIG. 6 is an explanatory diagram showing a basic operation principle 2 of the linear motor according to the present invention.
FIG. 7 is an explanatory diagram showing an outline of a conventional phase control drive linear motor.
FIG. 8 is an explanatory diagram of a conventional magnetic circuit.
FIG. 9 is an explanatory plan view of a conventional moving coil.
FIG. 10 is an explanatory diagram showing a relationship between a conventional yoke and a moving coil.
FIG. 11 is an assembly explanatory view showing the configuration of a conventional moving coil.
DESCRIPTION OF SYMBOLS 1 ... Yoke, 3 ... Movable coil, 5 ... Cavity, 12, 14 ... Side yoke, 16 ... Center yoke , 3A1 , 3A2 , 3B1 , 3B2 , 3C1 , 3C2 ... Coil member, 51, 52 ... Permanent magnet group

Claims

A linear motor having a yoke, a movable coil , a first permanent magnet group having a plurality of permanent magnets, and a second permanent magnet group having a plurality of permanent magnets,
The yoke is
A common yoke,
A first side yoke continuous to one end of the common yoke and orthogonal to the common yoke;
A second side yoke that is continuous with the other end of the common yoke, is orthogonal to the common yoke, and faces the first side yoke;
Said first side yoke, the common in the yoke and the cavity defined between the second side yoke, and a center yoke is located between the first and second side yokes to the opposed ,
Constituting the yoke, the common yoke, said first and second side yoke and the center yoke, the movable coil in the longitudinal direction of the moving coil is moved are formed in a range to move,
The first permanent magnet group has a plurality of permanent magnets disposed along the longitudinal direction on the surface of the first side yoke facing the second side yoke, and the plurality of permanent magnets. The magnet is arranged with different magnetic poles of adjacent permanent magnets,
The second permanent magnet group includes a plurality of permanent magnets arranged along the longitudinal direction on the surface of the second side yoke facing the first side yoke, and the plurality of permanent magnets. The magnets are arranged such that the magnetic poles of adjacent permanent magnets are different from each other, and the arrangement positions in the longitudinal direction are the same as those of the plurality of permanent magnets of the opposed first permanent magnet group. Magnetic poles are the same,
The movable coil has a first coil set composed of three first coil members,
The three first coil members have a cavity inserted through the center yoke at the center,
The longitudinal length of each of the three first coil members is 2/3 of the longitudinal length of each permanent magnet,
The three first coil members are arranged around the cavity and at intervals of 2/3 of the longitudinal length of each permanent magnet along the longitudinal direction .
The three first coil members are wound in the same direction in a direction perpendicular to the longitudinal direction of the center yoke, and the cross-sectional shape is flat with the surfaces facing the first and second side yokes being flat. It has a profile,
The longitudinal first coil pair of the longitudinal length having a direction disposed the previous SL three first coil member, said opposing said disposed in the first and second permanent magnets The first coil set and the plurality of permanent magnets are configured to be equal to the length in the longitudinal direction of four continuous permanent magnets arranged in the longitudinal direction of each group,
The front Symbol three first coil member, the phase difference each alternating current of 120 degrees is applied,
Linear motor.

The moving coil, wherein the length of each of the longitudinal and 2/3 of the longitudinal length of the permanent magnets, disposed continuously connected to each of the previous SL three first coil member respectively has been further have a second coil set consisting of three second coil member,
The second coil member is
Around the cavity, it is wound in the same winding direction as the previous SL first coil member,
It has the same rectangular outer shape as the first coil member,
Wherein the adjacent contact the first coil member to each of the second coil member, the second phase and reverse phase of the current phase of the current applied to the coil member is applied to the first coil member A current is applied,
The linear motor according to claim 1.

Each of the three first coil members and each of the three second coil members disposed adjacent to each of the three first coil members are coil portions of both. The end of winding is connected,
The alternating current applied to the first coil portion is applied to the winding start portion of the first coil member and the winding start portion of the second coil member adjacent to the corresponding first coil member.
The linear motor according to claim 2.

An alternating current having a phase difference applied to the other first coil members is applied to each of the three first coil members, and the second coil members adjacent to the first coil members are applied. An alternating current having a phase opposite to the phase of the alternating current applied to the adjacent first coil member is applied to each of them,
The linear motor according to claim 2.

The moving coil, wherein the length of each of the longitudinal and 2/3 of the longitudinal length of the permanent magnets, Zorezo Re is connected to respective front Symbol three first coil member And a second coil set composed of three second coil members ,
Each of the second coil member, the periphery of the cavity, and wound around the first coil member and the opposite winding direction the you neighbor,
An alternating current having a phase difference of 120 degrees is applied to each of the three first coil members,
Alternating current with a phase difference of 1 20 degrees to each of the three second coil member is applied,
The linear motor according to claim 1.

Each of the first and second coil members is formed by wet winding .
The linear motor in any one of Claims 1-5.