JP2004343930A

JP2004343930A - Actuator

Info

Publication number: JP2004343930A
Application number: JP2003139570A
Authority: JP
Inventors: Yuya Hasegawa; 祐也長谷川; Katsuhiro Hirata; 勝弘平田; Makoto Motohashi; 良本橋; Hiroaki Shimizu; 宏明清水; Hidekazu Yabuuchi; 英一薮内
Original assignee: Matsushita Electric Works Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 2003-05-16
Filing date: 2003-05-16
Publication date: 2004-12-02
Anticipated expiration: 2023-05-16
Also published as: JP4029774B2

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to achieve a small diameter and miniaturization of an actuator that performs reciprocative and rotating drives. <P>SOLUTION: A permanent magnet 2 is magnetized in the direction crossing the axial direction of a shaft 1. Yokes 5 are provided at both sides in the axial direction of the coil 4, and magnetic poles 7 are provided protrusively from the inside circumferential surface of the yokes 5 at both sides in the axial direction toward a movable element 3 side each in such a way as to face the permanent magnet 2. Positional relation of the position of the magnetic poles 7 provided on the yokes 5a, 5b at both sides in the circumferential direction on a shaft to the magnetic poles of the external surface of the permanent magnet 2 is set up in such a way that, when a current is impressed to the coil 4, repulsive and attractive magnetic relation between the magnetic poles of the magnetic pole 7 provided on one yoke 5a and the magnetic pole of the external surface side of the corresponding permanent magnet 2 is equalized to the repulsive and attractive magnetic relation between the magnetic poles 7 provided on the other yoke 5b and the magnetic poles of the external surface side of the corresponding permanent magnet 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、所定角度範囲で正逆回転して往復回転駆動を行うためのアクチュエータに関するものである。
【０００２】
【従来の技術】
従来から所定角度範囲で正逆回転して往復回転駆動を行うためのアクチュエータとして特許文献１が知られている。
【０００３】
この特許文献１に示された従来例は、シャフトと一体化した円周方向にＮ極とＳ極が順に着磁された永久磁石を有する可動子と、該可動子と同心円状に配置された一対のヨーク及びコイルを有する固定子とでアクチュエータを構成しており、一対のヨークからそれぞれ磁極歯部をシャフトと平行に突出させてこの両ヨークから突出させた磁極歯部の先端部を相手方のヨークに対向するように配置し、該磁極歯部の外側にコイルを配置している。
【０００４】
このような構成の特許文献１に示されたアクチュエータはコイルと可動子との間に磁極歯部が介在しているので、磁極歯部の分だけアクチュエータ全体の径が大きくなるという問題がある。このため、例えば、電動歯ブラシの駆動部としてアクチュエータを用いようとしても、電動歯ブラシの把持部となるハウジング内にアクチュエータを内装しようとすると、把持部の径が大きくなって、電動歯ブラシとしての使い勝手が悪くなってしまうという問題がある。このことは他の電気機器にアクチュエータを内装した場合も同様であり、アクチュエータを組込んだ電気機器の小型化の障害となっている。
【０００５】
【特許文献１】
特開２００１−０３７１９２号公報
【０００６】
【発明が解決しようとする課題】
本発明は、上記の従来例の問題点に鑑みて発明したものであって、その目的とするところは、磁気回路を利用した往復回転駆動をするアクチュエータの径を小さくできて小型化が実現できるアクチュエータを提供することにある。
【０００７】
【課題を解決するための手段】
上記課題を解決するために本発明に係るアクチュエータは、シャフト１に永久磁石２を設けてなる可動子３を、該可動子３を囲むように周方向に巻回されるコイル４と筒状の磁性体よりなるヨーク５とを備えた固定子６内に回動自在に支持し、コイル４に電流を印加して可動子３をシャフト１を中心として所定角度で往復回転運動させるようにしたアクチュエータであって、上記永久磁石２はシャフト１の軸方向と交差する方向に着磁されており、上記ヨーク５はコイル４の軸方向の両側に設けられると共に軸方向の両側のヨーク５の内周面から可動子３側に向けてそれぞれ上記永久磁石２と対向するように磁極部７が突設され、コイル４に電流を印加した時の一方のヨーク５ａに設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係と、他方のヨーク５ｂに設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるように両側のヨーク５ａ、５ｂに設けた磁極部７の軸周り方向の位置と、永久磁石２の外面の磁極との位置関係を設定して成ることを特徴とするものである。
【０００８】
このような構成とすることで、コイル４に一方向の電流を流すと一方のヨーク５ａの磁極部７がＮ極側、他方のヨーク５ｂの磁極部７がＳ極側となり、各磁極部７とこれに対応する永久磁石２の外面側の磁極との磁気的な反発、吸引によりシャフト１が所定角度で往復回転運動を行うのであるが、この場合、コイル４に電流を印加した時の一方のヨーク５に設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係と、他方のヨーク５に設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるように両側のヨーク５ａ、５ｂに設けた磁極部７の軸周り方向の位置と、永久磁石２の外面の磁極との位置関係を設定してあることで、可動子３が高効率、高トルクの往復回転駆動を行うことができるものである。そして、コイル４の軸方向の両側に設けたヨーク５ａ、５ｂの内周から可動子３側に向けてそれぞれ上記永久磁石２と対向するように磁極部７が突設してあるので、磁極部７がコイル４と可動子３との間に介在されず、したがって、磁極歯部の外周にコイル４を配置する（つまりコイル４内周と可動子３の外周との間に磁極歯部が位置する）従来例に比べてアクチュエータの径を小さくでき、小型化を図ることができるものであり、例えば、電動歯ブラシの駆動部として本発明のアクチュエータを使用することで、電動歯ブラシのアクチュエータを内装する把持部の径を小さくできて、使い勝手を向上することができるものである。
【０００９】
また、シャフト１が磁性体であることが好ましい。
【００１０】
このようにシャフト１を磁性体とすることで、起磁力側から見た磁気回路の磁気抵抗を減らし、磁束量を増やしてトルクを上げることができ、よりいっそう高効率、高トルクな回転駆動を可能とするものである。
【００１１】
また、コイル４の軸方向の両側に配設した両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７をシャフト１を中心に軸周り方向にずらすことが好ましい。
【００１２】
このようにコイル４の両側に配設した両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７を筒状の固定子６の軸周りにずらすという構成を採用することで、コイル４に電流を印加した時の一方のヨーク５ａに設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係と、他方のヨーク５ｂに設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるようにできて、簡単な構成で高効率、高トルクのアクチュエータを実現できるものである。
【００１３】
また、一方のヨーク５ａに設けた磁極部７と他方のヨーク５ｂに設けた磁極部７とを軸周り方向において一致させ、一方のヨーク５ａに設けた磁極部７に対応する永久磁石２の外面の磁極と、上記永久磁石２と軸周りにおいて一致する位置に設けた他方のヨーク５ｂから突設した磁極部７に対応する永久磁石２の外面の磁極の磁性を異ならせることが好ましい。
【００１４】
このような構成とすることで、簡単な構成で、コイル４に電流を印加した時の一方のヨーク５に設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係と、他方のヨーク５ａに設けた磁極部７の磁極と、これに対応する永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるようにできて、高効率、高トルクのアクチュエータを実現できるものである。
【００１５】
また、シャフト１の外周部に磁性体と永久磁石２とを設けると共に磁性体の外面部と永久磁石２の外面部とが軸周り方向に並設していることが好ましい。
【００１６】
このような構成とすることで、永久磁石２の軸周り方向の隣の磁性体の外面部が永久磁石２の外面部の磁極と異なる磁極となって磁石として機能し軸周りに異なる磁極が存在することになり、高価な永久磁石の使用数量を減らすことができて、低コストのアクチュエータを実現できるものである。更に、起磁力側から見た磁気抵抗を低下することができる。
【００１７】
また、シャフト１に磁極部７を設けた可動子３を、該可動子３を囲むように周方向に巻回されるコイル４と永久磁石２とを有してなる固定子６内に回動自在に支持し、コイル４に電流を印加して可動子３をシャフト１を中心として所定角度で往復回転運動させるようにしたアクチュエータであって、上記永久磁石２はコイル４の軸方向の両側にそれぞれ設けられると共に永久磁石２はシャフト１の軸方向と交差する方向に着磁されており、磁極部７はシャフト１の軸方向に間隔を隔てた位置からそれぞれ上記コイル４の軸方向の両側に設けた永久磁石２とそれぞれ対向するようにシャフト１から突設され、コイル４に電流を印加した時の軸方向に間隔を隔てた一方の磁極部７の磁極と、これに対応する永久磁石２の内面側の磁極との反発、吸引の磁気的関係と、軸方向に間隔を隔てた他方の磁極部７の磁極と、これに対応する永久磁石２の内面側の磁極との反発、吸引の磁気的関係とが同じとなるように軸方向の両側の磁極部７の軸周り方向の位置と、永久磁石２の内面の磁極との位置関係を設定して成ることを特徴とするものであってもよい。
【００１８】
このような構成とすることで、シャフト１に軸方向に間隔を隔てて設けた両側の磁極部７のうち一方の磁極部７がＮ極側、他方の磁極部７がＳ極側となり、各磁極部７とこれに対応する永久磁石２の内面側の磁極との磁気的な反発、吸引によりシャフト１が所定角度で往復回転運動を行うのであるが、この場合、コイル４に電流を印加した時の軸方向に間隔を隔てた一方の磁極部７の磁極と、これに対応する永久磁石２の内面側の磁極との反発、吸引の磁気的関係と、軸方向に間隔を隔てた他方の磁極部７の磁極と、これに対応する永久磁石２の内面側の磁極との反発、吸引の磁気的関係とが同じとなるように軸方向の両側の磁極部７の軸周り方向の位置と、永久磁石２の内面の磁極との位置関係を設定してあることで、可動子３が高効率、高トルクの往復回転駆動を行うことができるものである。そして、永久磁石２がコイル４の軸方向の両側にそれぞれ設けられ、永久磁石２がシャフト１の軸方向と交差する方向に着磁されており、磁極部７がシャフト１の軸方向に間隔を隔てた位置からそれぞれ上記コイル４の軸方向の両側に設けた永久磁石２とそれぞれ対向するようにシャフト１から突設してあるので、磁極部７がコイル４と可動子３との間に介在されず、したがって、磁極歯部の外周にコイル４を配置する（つまりコイル４内周と可動子３の外周との間に磁極歯部が位置する）従来例に比べてアクチュエータの径を小さくでき、小型化を図ることができるものであり、また、磁極部７がシャフト１の軸方向に間隔を隔てた位置からそれぞれ上記コイル４の軸方向の両側に設けた永久磁石２とそれぞれ対向するようにシャフト１から突設してあるので、シャフト１から遠い所で力が発生する対向面積を広く取れて大きなトルクを発生させることができる。そして、例えば、電動歯ブラシの駆動部として本発明のアクチュエータを使用することで、電動歯ブラシのアクチュエータを内装する把持部の径を小さくできて、使い勝手を向上することができるものである。
【００１９】
【発明の実施の形態】
以下、本発明を添付図面に基づいて説明する。
【００２０】
図１乃至図４には本発明の一実施形態が示してあり、
アクチュエータは軸周りに回転自在に支持された可動子３と、この可動子３が軸周りに回動自在に挿通される筒状をした固定子６とで構成してある。
【００２１】
図１に示すように、筒状（実施形態では円筒状）をした磁性体よりなるシールドケース９内に筒状をした固定子６を内装してある。固定子６はコイルボビン１０にコイル４を巻装すると共に該コイルボビン１０の両側に内径がコイルボビン１０よりも小径となった筒状をしたヨーク５（ヨーク５ａ、ヨーク５ｂ）を設け、両側のヨーク５ａ、５ｂを磁性体１１で磁気的に接続し、両側のヨーク５ａ、５ｂの内周部からそれぞれ複数の磁極部７を可動子３側に向けて突出することで構成してある。
【００２２】
ここで、図１に示す実施形態においてはコイル４の両側に配置されたヨーク５ａ、５ｂを別体の筒状の磁性体１１で磁気的に接続して両側のヨーク５ａ、５ｂと磁性体１１とで一つのヨーク体を構成しているが、両側のヨーク５ａ、５ｂを磁性体よりなるシールドケース９により磁気的に接続して両側のヨーク５ａ、５ｂとシールドケース９とで一つのヨーク体を形成してもよく、あるいは、両側のヨーク５ａ、５ｂと磁性体１１とが一体化して一体のヨーク体を構成してもよいものである。
【００２３】
図１乃至図３に示す実施形態ではコイル４の両側に配置された各ヨーク５ａ、５ｂの内周部からそれぞれ２個の磁極部７が突出してあり、一方のヨーク５ａに設けた２個の磁極部７は筒状の固定子６の軸周り方向に１８０°離れて位置しており、また、他方のヨーク５ｂに設けた２個の磁極部７は筒状の固定子６の軸周り方向に１８０°離れて位置しており、更に、一方のヨーク５ａに設けた磁極部７と他方のヨーク５ｂに設けた磁極部７とは筒状をした固定子６の軸周り方向においてずれており、本実施形態では一方のヨーク５ａに設けた磁極部７と他方のヨーク５ｂに設けた磁極部７とは筒状をした固定子６の軸周り方向において９０°ずれている例が示してある。
【００２４】
可動子３はシャフト１の外周部に永久磁石２を設けて構成してある。ここで、本発明においては、磁気抵抗を減らし、磁束量を増やしてトルクを上げ、高効率、高トルクな回転駆動を可能とすることを目的として上記永久磁石２を設けるシャフト１を磁性体により構成してある。可動子３は回転方向に自在に回転できるように筒状をしたシールドケース９の軸方向の両端部に設けた軸受け部１２にシャフト１を回転自在に保持してあって、この可動子１はシールドケース９内において固定子６内に所定のギャップを隔てて挿通してある。また、可動子１は永久磁石２を設けた部分の軸方向における両側をばね等の弾性体１３により連結してあり、可動子３と弾性体１３とでシャフト１を中心とする往復回転運動の振動系を構成している。
【００２５】
永久磁石２はシャフト１の軸周りに複数個設けてあり、複数の永久磁石２はいずれもシャフト１の軸方向と交差する方向の外面と内面とが図２、図３に示すように異極となるように着磁されており、しかも、軸周り方向に隣接する永久磁石２の外面の磁極同士が異極となっている。つまり、軸周り方向にＮ極とＳ極とが交互に着磁してある。図２、図３に示す実施形態ではシャフト１の外周に軸周り方向に４個の永久磁石２が設けてあり、この４個の永久磁石２はその外面の磁極が交互にＮ極とＳ極となるように着磁してある。
【００２６】
ここで、両ヨーク５ａ、５ｂに設けた磁極部７と、これらの磁極部７と対向する永久磁石２の外面の磁極との関係は以下のように設定してある。すなわち、コイルに４に電流を流した場合に、一方のヨーク５ａに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係で可動子と、他方のヨーク５ｂに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるように両側のヨーク５ａ、５ｂに設けた磁極部７の軸周り方向の位置と、永久磁石２の外面の磁極との位置関係を設定してある。つまり、一方のヨーク５ａに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係により可動子３を軸周り回転させるトルクを発生させる際、他方のヨーク５ｂに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係により可動子３を上記と同方向に回転させるトルクを発生させるように、両側のヨーク５ｂに設けた磁極部７と、これにそれぞれ対向する永久磁石２との磁気的関係を設定してある。
【００２７】
次に、図３に基づいて動作原理を説明する。コイル４に一方向の電流を流すとコイル４の軸方向の一方のヨーク５ａに設けた磁極部７と、コイル４の軸方向の他方のヨーク５ｂに設けた磁極部７とに異なる極が発生する。例えば、図３のように、軸方向の一方のヨーク５ａに設けた磁極部７にＮ極が生じ、他方側に位置する位置するヨーク５ｂに設けた磁極部７にＳ極が生じたとすると、コイル４の両側の両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７と可動子３の永久磁石２との間には図３（ａ）、（ｂ）に示すようにそれぞれ時計回りのトルクが生じ、可動子３が時計回りに回転する。また、コイル４に他方向の電流を流すとコイル４の軸方向の一方のヨーク５ａに設けた磁極部７と、コイル４の軸方向の他方のヨーク５ｂに設けた磁極部７とに異なる極が発生し、コイル４の両側の両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７と可動子３の永久磁石２との間にはそれぞれ上記とは逆の反時計回りのトルクが生じ、可動子３が反時計回りに回転する。したがって、コイル４に交番電流を流すことによって可動子３をシャフトを中心として所定角度で往復回転運動させることができるものである。また、図４にはトルク特性を示しており、図３の状態を角度０°として±４５°での電流を流していない時、一方向の電流を流している時、他方向の電流を流している時のトルクを示しており、角度０°の位置で単位電流当たりのトルクが一番大きくなる。そして、図４においてＭで示す範囲中で本発明における可動子３の往復回転運動する所定角度を設定するものである。
【００２８】
ところで、上記のように、コイル４の軸方向の両側に設けたヨーク５ａ、５ｂの内周から可動子３側に向けてそれぞれ上記永久磁石２と対向するように磁極部７を突設しているので、磁極部７はコイル４と可動子３との間に介在されない構成となっている。この構成により既に述べたコイル４と可動子３の永久磁石との間に磁極部となる磁極歯部を配置する従来例に比べてアクチュエータの径を小さくできるものである。したがって、アクチュエータの小径化、小型化が図れ、アクチュエータを用いた各種電気機器、例えは、本発明のアクチュエータを電動歯ブラシの把持部に内装して電動歯ブラシの駆動源とした場合、把持部の径を小さくできて、電動歯ブラシとしての使い勝手が良くなるものである。
【００２９】
次に、本発明の他の実施形態を図５、図６に基づいて説明する。本実施形態は基本的な構成は前述の図１乃至図４に示す実施形態と同じであるので、重複する説明は省略し、異なる構成につき説明する。
【００３０】
本実施形態においては、コイル４の両側にヨーク５ａ、５ｂを配置し、両側のヨーク５ａ、５ｂの内周部からそれぞれ複数の磁極部７を可動子３側に向けて突出することで固定子６を構成している。ここで、本実施形態では一方のヨーク５ａに設けた磁極部７と他方のヨーク５ｂに設けた磁極部７とを軸周り方向において一致させてある。図６（ａ）、（ｂ）に示すように、一方のヨーク５ａの内周から複数の磁極部７が突設してあり（実施形態では４個の磁極部７が軸周り方向に９０°の間隔を隔てて突設してあり）、また、他方のヨーク５ｂの内周から上記一方のヨーク５ａに突設した磁極部７と同数の磁極部７が突設してあり（実施形態では４個の磁極部７が軸周り方向に９０°の間隔を隔てて突設してあり）、図６（ａ）に示す複数の磁極部７と図６（ｂ）に示す複数の磁極部７とは軸周り方向において一致している。
【００３１】
可動子３は磁性体よりなるシャフト１の外周部に永久磁石２を設けて構成してある。本実施形態では、図５、図６に示すように、一方のヨーク５ａに突設した磁極部７と対向するシャフト１の外周部において軸周り方向に複数個（実施形態では８個）の永久磁石２が設けてあり、更に、他方のヨーク５ｂに突設した磁極部７と対向するシャフト１の外周部において軸周り方向に上記とは別の複数個（実施形態では８個）の永久磁石２が設けてある。上記全ての永久磁石２はいずれもシャフト１の軸方向と交差する方向の外面と内面とが図５、図６に示すように異極となるように着磁されており、また、一方のヨーク５ａに突設した磁極部７と対向する複数の永久磁石２は軸周り方向に隣接する永久磁石２の外面の磁極同士が異極となるようにＮ極とＳ極を交互に着磁してあり、更に、他方のヨーク５ｂに突設した磁極部７と対向する複数の永久磁石２は軸周り方向に隣接する永久磁石２の外面の磁極同士が異極となるようにＮ極とＳ極を交互に着磁してあり、更に、軸周り方向において一致する位置において軸方向に隣合う永久磁石２の外面の磁極同士が異極となっている。
【００３２】
このように本実施形態においては、一方のヨーク５ａに設けた磁極部７と他方のヨーク５ｂに設けた磁極部７とを軸周り方向において一致させ、一方のヨーク５ａに設けた磁極部７に対応する永久磁石２の外面の磁極と、上記永久磁石２と軸周りにおいて一致する位置に設けた他方のヨーク５ｂから突設した磁極部７に対応する永久磁石２の外面の磁極の磁性を異ならせることにより、コイルに４に電流を流した場合に、一方のヨーク５ａに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係と、他方のヨーク５ｂに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるように構成している。
【００３３】
本実施形態の動作原理を図６により説明する。コイル４に一方向の電流を流すとコイル４の軸方向の一方のヨーク５ａに設けた磁極部７と、コイル４の軸方向の他方のヨーク５ｂに設けた磁極部７とに異なる極が発生する。例えば、図６のように、軸方向の一方のヨーク５ａに設けた磁極部７にＮ極が生じ、他方側に位置するヨーク５ｂに設けた磁極部７にＳ極が生じたとすると、コイル４の両側の両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７とこれらの磁極部７と対向する各永久磁石２との間には図６（ａ）、（ｂ）に示すようにそれぞれ時計回りのトルクが生じ、可動子３が時計回りに回転する。また、コイル４に他方向の電流を流すとコイル４の軸方向の一方のヨーク５ａに設けた磁極部７と、コイル４の軸方向の他方のヨーク５ｂに設けた磁極部７とに異なる極が発生し、コイル４の両側の両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７とこれらの磁極部７と対向する各永久磁石２との間にはそれぞれ上記とは逆の反時計回りのトルクが生じ、可動子３が反時計回りに回転する。したがって、コイル４に交番電流を流すことによって可動子３をシャフトを中心として所定角度で往復回転運動させることができるものである。
【００３４】
次に、本発明の更に他の実施形態を図７、図８、図９に基づいて説明する。本実施形態は基本的な構成は前述の図１乃至図４に示す実施形態と同じであるので、重複する説明は省略し、異なる構成につき説明する。
【００３５】
本実施形態においては、固定子６の構成は前述の図１乃至図３に示す実施形態とほぼ同じである（なお、図９においては両側のヨーク５ａ、５ｂの内周からそれぞれ軸周り方向に９０°の間隔を隔てて４つずつの磁極部７を設けている点が図３と異なるが本実施形態において磁極部７の数には限定はない）。
【００３６】
本実施形態において可動子３は、磁性体よりなるシャフト１の外周部には磁性体よりなる磁性部材８を装着すると共に磁性部材８の外周面に周方向に所定間隔（図８、図９では９０°の間隔）で永久磁石２を埋め込んで構成してある。
【００３７】
すなわちシャフト１に被嵌して固着された円筒状をした磁性部材８の外周部の周方向の４箇所に設けた凹部１５に平板状をした棒磁石よりなる永久磁石２が埋設してあって、可動子３の外面には軸周り方向において永久磁石２の外面と磁性部材８の外面とが交互に位置した状態となっており、また、上記永久磁石２はシャフト１と交差する方向の外面と内面とで極が異なるように着磁してあると共に、全ての永久磁石２の外面が同一極となっている。
【００３８】
そして、本実施形態においても、両ヨーク５ａ、５ｂに設けた磁極部７と、これらの磁極部７と対向する永久磁石２の外面の磁極との関係は図１乃至図３に示す実施形態と同様に、コイル４の軸方向の両側に配設した両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７を軸周り方向にずらす構成とすることで、コイルに４に電流を流した場合に、一方のヨーク５ａに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係と、他方のヨーク５ｂに設けた磁極部７の磁極と、これと対向する可動子３の永久磁石２の外面側の磁極との反発、吸引の磁気的関係とが同じとなるようにしてある。
【００３９】
本実施形態の動作原理を図９に基づいて説明する。コイル４に一方向の電流を流すとコイル４の軸方向の一方のヨーク５ａに設けた磁極部７と、コイル４の軸方向の他方のヨーク５ｂに設けた磁極部７とに異なる極が発生する。例えば、図９のように、軸方向の一方のヨーク５ａに設けた磁極部７にＮ極が生じ、他方側に位置する位置するヨーク５ｂに設けた磁極部７にＳ極が生じたとすると、コイル４の両側の両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７と可動子３の永久磁石２との間には図９（ａ）、（ｂ）に示すようにそれぞれ時計回りのトルクが生じ、可動子３が時計回りに回転する。また、コイル４に他方向の電流を流すとコイル４の軸方向の一方のヨーク５ａに設けた磁極部７と、コイル４の軸方向の他方のヨーク５ｂに設けた磁極部７とに異なる極が発生し、コイル４の両側の両ヨーク５ａ、５ｂにそれぞれ設けた磁極部７と可動子３の永久磁石２との間にはそれぞれ上記とは逆の反時計回りのトルクが生じ、可動子３が反時計回りに回転する。したがって、コイル４に交番電流を流すことによって可動子３をシャフトを中心として所定角度で往復回転運動させることができるものである。
【００４０】
上記のような本実施形態においては、永久磁石２の軸周り方向の隣の磁性部材８の外面部が永久磁石２の外面部の磁極と異なる磁極となって磁石として機能して軸周りに異なる磁極が存在することになり、前述の各実施形態のものに比べて高価な永久磁石２の使用数量を減らすことができて、低コストのアクチュエータを実現できるものであり、更に、起磁力側から見た磁気抵抗を低下することができる。
【００４１】
次に、本発明の更に他の実施形態を図１０、図１１に基づいて説明する。
【００４２】
前述の各実施形態では永久磁石２を可動子３側に設け、磁極部７を固定子６側に設けたが、本実施形態においては、永久磁石２を固定子６側に設け、磁極部７を磁性体よりなるシャフト１側に設けた点が上記各実施形態と異なっている。
【００４３】
すなわち、コイル４の軸方向の両側にそれぞれ筒状に永久磁石２を配設して固定子６を構成してある。具体的には図１０、図１１に示すようにコイル４の軸方向の両側においてそれぞれ複数（実施形態では４個の）の断面円弧状をした永久磁石２を軸周り方向に並設して筒状磁石を構成してあり、この両筒状磁石はいずれも内径がコイル４の内径（実際は図示を省略しているがコイルボビンの内径）よりも大きいものである。上記全ての永久磁石２は軸と交差する方向の内面と外面とが異極となるように着磁してある。また、コイル４の軸方向の両側のうち一方側において軸周り方向に並設された複数の永久磁石２は図１１（ａ）のように軸周り方向に隣接する永久磁石２の内面の磁極が異なっている。また、コイル４の軸方向の両側のうち他方側において軸周り方向に並設された複数の永久磁石２は図１１（ｂ）のように軸周り方向に隣接する永久磁石２の内面の磁極が異なっている。そして、図１０、図１１に示す実施形態ではコイル４の軸方向の一方側において軸周り方向に並設した複数の永久磁石２と、コイル４の軸方向の他方側において軸周り方向に並設した複数の永久磁石２とは、軸方向において一致する永久磁石２同士の内面側の磁極が同じとなっている。
【００４４】
磁性体よりなるシャフト１の軸方向に間隔を隔てた位置からそれぞれ上記コイル４の軸方向の両側に設けた永久磁石２とそれぞれ対向するように磁極部７が突設してあり、実施形態においては図１１（ａ）に示すように、コイル４の軸方向の一方側において軸周り方向に並設した複数の永久磁石２よりなる筒状磁石に対応して軸方向と交差する２つの磁極部７が軸周り方向に１８０°の間隔を隔てて突設してあり、また、図１１（ｂ）に示すように、コイル４の軸方向の他方側において軸周り方向に並設した複数の永久磁石２よりなる筒状磁石に対応して軸方向と交差する２つの磁極部７が軸周り方向に１８０°の間隔を隔てて突設してあり、更に、図１１（ａ）に示す磁極部７と図１１（ｂ）に示す磁極部７とは軸周り方向に９０°ずれている。このような構成とすることで、コイル４に電流を印加した時の軸方向に間隔を隔てた一方の磁極部７の磁極と、これに対応する永久磁石２の内面側の磁極との反発、吸引の磁気的関係と、軸方向に間隔を隔てた他方の磁極部７の磁極と、これに対応する永久磁石２の内面側の磁極との反発、吸引の磁気的関係とが同じとなるようにしてある。
【００４５】
図１１に基づいて本実施形態の動作原理を説明する。コイル４に一方向の電流を流すとコイル４の軸方向の両側に配置した永久磁石２のうち一方の永久磁石２と対向する方の磁極部７と、コイル４の軸方向の両側に配置した永久磁石２のうち他方の永久磁石２と対向する方の磁極部７とに異なる極が発生する。例えば、図１１（ａ）の磁極部７にＮ極が生じ、他方側に位置する位置する図１１（ｂ）の磁極部７にＳ極が生じたとすると、コイル４の両側の両永久磁石２とこれらの永久磁石２と対向する各磁極部７との間には図１１（ａ）、（ｂ）に示すようにそれぞれ時計回りのトルクが生じ、可動子３が時計回りに回転する。また、コイル４に他方向の電流を流すと上記両側の磁極部７にそれぞれ上記とは逆の極が発生し、図１１（ａ）、（ｂ）の矢印とは逆の反時計回りのトルクが生じ、可動子３が反時計回りに回転する。したがって、コイル４に交番電流を流すことによって可動子３をシャフトを中心として所定角度で往復回転運動させることができるものである。
【００４６】
本実施形態においては、永久磁石２をコイル４の軸方向の両側にそれぞれ設け、永久磁石２をシャフト１の軸方向と交差する方向に着磁し、磁極部７をシャフト１の軸方向に間隔を隔てた位置からそれぞれ上記コイル４の軸方向の両側に設けた永久磁石２とそれぞれ対向するようにシャフト１から突設するので、磁極部７がコイル４と可動子３との間に介在されない構成となっている。この構成により既に述べたコイル４と可動子３の永久磁石との間に磁極部となる磁極歯部を配置する従来例に比べてアクチュエータの径を小さくでき、したがって、アクチュエータの小径化、小型化が図れるものである。また、磁極部７がシャフト１の軸方向に間隔を隔てた位置からそれぞれ上記コイル４の軸方向の両側に設けた永久磁石２とそれぞれ対向するようにシャフト１から突設してあるので、シャフト１から遠い所で力が発生する対向面積を広く取れて大きなトルクを発生させることができる。
【００４７】
そして、本実施形態のアクチュエータを用いた各種電気機器、例えは、本発明のアクチュエータを電動歯ブラシの把持部に内装して電動歯ブラシの駆動源とした場合、把持部の径を小さくできて、電動歯ブラシとしての使い勝手が良くなるものである。
【００４８】
なお、軸方向の一方側における磁極部７と永久磁石２との磁気的関係、軸方向の他方側における磁極部７と永久磁石２との磁気的関係が、軸方向の一方側において磁極部７と永久磁石２との間に一方向に回転するトルクが発生し、軸方向の他方側において磁極部７と永久磁石２との間に反対方向に回転するトルクが発生するようになっていても、一方向又は逆方向に回転するトルクのうち何れか一方が大で他方が小となる関係となっている場合も、大きなトルクが発生する方に回動して往復回転運動を行うことができる。
【００４９】
【発明の効果】
上記のように本発明の振動型アクチュエータにおいては、磁極部がコイルと可動子との間に介在されず、従来のようにコイル内周と可動子の外周との間に磁極歯部が位置するものに比べてアクチュエータの径を小さくできて小型化を図ることができ、また、可動子を高効率、高トルクで往復回転駆動を行うことができるものである。
【図面の簡単な説明】
【図１】本発明のアクチュエータの全体構造を示す断面図である。
【図２】同上のアクチュエータの要部を軸方向と平行な方向で破断した斜視図である。
【図３】同上の動作原理のための説明図であり、（ａ）は一方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図であり、（ｂ）は他方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図である。
【図４】同上のトルク特性を示すグラフである。
【図５】同上の他の実施形態のアクチュエータの要部を軸方向と平行な方向で破断した斜視図である。
【図６】同上の動作原理のための説明図であり、（ａ）は一方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図であり、（ｂ）は他方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図である。
【図７】同上の更に他の実施形態のアクチュエータの全体構造を示す断面図である。
【図８】同上の他の実施形態のアクチュエータの要部を軸方向と平行な方向で破断した斜視図である。
【図９】同上の動作原理のための説明図であり、（ａ）は一方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図であり、（ｂ）は他方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図である。
【図１０】同上の更に他の実施形態のアクチュエータの要部を軸方向と平行な方向で破断した斜視図である。
【図１１】同上の動作原理のための説明図であり、（ａ）は一方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図であり、（ｂ）は他方のヨークに設けた磁極部と可動子の永久磁石との関係を示す断面図である。
【符号の説明】
１シャフト
２永久磁石
３可動子
４コイル
５ヨーク
６固定子
７磁極部
８磁性体[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an actuator for performing a reciprocating rotation drive by rotating forward and backward in a predetermined angle range.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, Japanese Patent Application Laid-Open Publication No. HEI 11-163556 discloses an actuator for performing reciprocal rotation by performing forward and reverse rotation within a predetermined angle range.
[0003]
In the conventional example disclosed in Patent Document 1, a mover having a permanent magnet in which a north pole and a south pole are sequentially magnetized in a circumferential direction integrated with a shaft and a concentric circle are arranged with the mover. An actuator is constituted by a pair of yokes and a stator having a coil, and the magnetic pole teeth are respectively projected from the pair of yokes in parallel with the shaft, and the tips of the magnetic pole teeth protruding from the two yokes are opposed to each other. The coil is arranged so as to face the yoke, and the coil is arranged outside the magnetic pole teeth.
[0004]
Since the magnetic pole teeth are interposed between the coil and the mover in the actuator disclosed in Patent Literature 1 having such a configuration, there is a problem that the diameter of the entire actuator is increased by the magnetic pole teeth. For this reason, for example, even if an actuator is used as a driving unit of the electric toothbrush, if the actuator is to be provided in a housing serving as a holding unit of the electric toothbrush, the diameter of the holding unit becomes large, and the usability as the electric toothbrush is increased. There is a problem that it gets worse. This is the same also when an actuator is built in another electric device, which is an obstacle to miniaturization of the electric device incorporating the actuator.
[0005]
[Patent Document 1]
JP 2001-037192 A
[0006]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the problems of the conventional example described above, and has as its object to reduce the diameter of an actuator that performs reciprocal rotation drive using a magnetic circuit, thereby realizing miniaturization. It is to provide an actuator.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, an actuator according to the present invention comprises a movable member 3 having a shaft 1 provided with a permanent magnet 2 and a coil 4 wound in a circumferential direction so as to surround the movable member 3. An actuator rotatably supported in a stator 6 having a yoke 5 made of a magnetic material and applying a current to the coil 4 to reciprocally move the mover 3 around the shaft 1 at a predetermined angle. The permanent magnet 2 is magnetized in a direction intersecting the axial direction of the shaft 1. The yokes 5 are provided on both sides of the coil 4 in the axial direction, and the inner circumferences of the yokes 5 on both sides in the axial direction. A magnetic pole portion 7 is protruded from the surface toward the mover 3 so as to be opposed to the permanent magnet 2, and a magnetic pole of the magnetic pole portion 7 provided on one yoke 5 a when a current is applied to the coil 4, Corresponding outer surface of permanent magnet 2 And the magnetic relationship between the magnetic pole of the magnetic pole portion 7 provided on the other yoke 5b and the corresponding magnetic pole on the outer surface of the permanent magnet 2 with respect to the magnetic repulsion and attraction. In the same manner, the positional relationship between the magnetic pole portions 7 provided on the yokes 5a and 5b on both sides in the direction around the axis and the magnetic poles on the outer surface of the permanent magnet 2 is set.
[0008]
With such a configuration, when a current in one direction flows through the coil 4, the magnetic pole part 7 of one yoke 5a becomes the N pole side and the magnetic pole part 7 of the other yoke 5b becomes the S pole side, and each magnetic pole part 7 The shaft 1 performs a reciprocating rotational movement at a predetermined angle due to magnetic repulsion and attraction of the magnetic poles on the outer surface side of the permanent magnet 2 with the corresponding magnetic poles. The magnetic relationship of repulsion and attraction between the magnetic pole of the magnetic pole portion 7 provided on the yoke 5 and the corresponding magnetic pole on the outer surface side of the permanent magnet 2, and the magnetic pole of the magnetic pole portion 7 provided on the other yoke 5, The position of the magnetic pole portion 7 provided on the yokes 5a and 5b on both sides in the direction around the axis so that the magnetic relationship of repulsion and attraction to the magnetic pole on the outer surface side of the permanent magnet 2 corresponding thereto is the same. By setting the positional relationship with the magnetic pole on the outer surface of 2, the mover 3 is highly effective. , It is capable of performing a reciprocating rotary drive high torque. The magnetic pole portions 7 project from the inner circumferences of the yokes 5a and 5b provided on both sides in the axial direction of the coil 4 toward the mover 3 so as to face the permanent magnets 2 respectively. 7 is not interposed between the coil 4 and the mover 3, so that the coil 4 is arranged on the outer periphery of the magnetic pole teeth (that is, the magnetic pole teeth are located between the inner periphery of the coil 4 and the outer periphery of the mover 3). The diameter of the actuator can be reduced and the size can be reduced as compared with the conventional example. For example, by using the actuator of the present invention as a driving unit of the electric toothbrush, the actuator of the electric toothbrush is installed. The diameter of the grip can be reduced, and the usability can be improved.
[0009]
Preferably, the shaft 1 is made of a magnetic material.
[0010]
By using the shaft 1 as a magnetic material in this way, it is possible to reduce the magnetic resistance of the magnetic circuit as viewed from the magnetomotive force side, increase the amount of magnetic flux, and increase the torque, and achieve even higher efficiency and high torque rotational driving. It is possible.
[0011]
Further, it is preferable that the magnetic pole portions 7 provided on both yokes 5a and 5b disposed on both sides of the coil 4 in the axial direction are shifted in the direction around the axis about the shaft 1.
[0012]
As described above, the current is applied to the coil 4 by adopting a configuration in which the magnetic pole portions 7 provided on both the yokes 5a and 5b disposed on both sides of the coil 4 are shifted around the axis of the cylindrical stator 6. The magnetic relationship between the magnetic pole of the magnetic pole portion 7 provided on one yoke 5a and the corresponding magnetic pole on the outer surface side of the permanent magnet 2 at the time, and the magnetic relationship of the magnetic pole portion 7 provided on the other yoke 5b. The magnetic poles and the corresponding magnetic poles on the outer surface side of the permanent magnet 2 corresponding to the magnetic poles can be made to have the same magnetic relationship of repulsion and attraction, thereby realizing an actuator with high efficiency and high torque with a simple configuration. is there.
[0013]
Also, the magnetic pole portion 7 provided on one yoke 5a and the magnetic pole portion 7 provided on the other yoke 5b are aligned in the direction around the axis, and the outer surface of the permanent magnet 2 corresponding to the magnetic pole portion 7 provided on the one yoke 5a. It is preferable that the magnetism of the outer magnetic pole of the permanent magnet 2 corresponding to the magnetic pole portion 7 projecting from the other yoke 5b provided at a position coinciding with the permanent magnet 2 around the axis is different.
[0014]
With such a configuration, the magnetic pole of the magnetic pole portion 7 provided on one yoke 5 when a current is applied to the coil 4 and the corresponding magnetic pole on the outer surface side of the permanent magnet 2 are formed with a simple configuration. The magnetic relationship between the repulsion and the attraction and the magnetic relationship between the magnetic pole of the magnetic pole portion 7 provided on the other yoke 5a and the corresponding magnetic pole on the outer surface of the permanent magnet 2 are the same. Thus, an actuator with high efficiency and high torque can be realized.
[0015]
Further, it is preferable that the magnetic body and the permanent magnet 2 are provided on the outer peripheral portion of the shaft 1 and that the outer surface of the magnetic body and the outer surface of the permanent magnet 2 are arranged side by side around the axis.
[0016]
With such a configuration, the outer surface of the magnetic body adjacent to the permanent magnet 2 in the direction around the axis becomes a magnetic pole different from the magnetic pole of the outer surface of the permanent magnet 2 and functions as a magnet, and there is a different magnetic pole around the axis. Thus, the number of expensive permanent magnets used can be reduced, and a low-cost actuator can be realized. Further, the magnetic resistance viewed from the magnetomotive force side can be reduced.
[0017]
Further, the mover 3 having the magnetic pole portion 7 provided on the shaft 1 is rotated inside a stator 6 having a coil 4 and a permanent magnet 2 wound in a circumferential direction so as to surround the mover 3. An actuator which is freely supported and applies a current to the coil 4 to reciprocately move the mover 3 around the shaft 1 at a predetermined angle. The permanent magnet 2 is provided on both sides of the coil 4 in the axial direction. The permanent magnets 2 are provided and are magnetized in a direction intersecting with the axial direction of the shaft 1. The magnetic pole portions 7 are provided on both sides in the axial direction of the coil 4 from positions spaced apart in the axial direction of the shaft 1. The magnetic poles of one of the magnetic pole portions 7 protruding from the shaft 1 so as to face the provided permanent magnets 2 and being spaced apart in the axial direction when a current is applied to the coil 4, and the corresponding permanent magnets 2. Repulsion and absorption with the inner magnetic pole And the magnetic relationship of repulsion and attraction between the magnetic pole of the other magnetic pole portion 7 spaced apart in the axial direction and the corresponding magnetic pole on the inner surface side of the permanent magnet 2 is set to be the same. It may be characterized in that the positional relationship between the positions of the magnetic pole portions 7 on both sides in the axial direction around the axis and the magnetic poles on the inner surface of the permanent magnet 2 is set.
[0018]
With such a configuration, of the magnetic pole portions 7 on both sides provided at an interval in the axial direction on the shaft 1, one magnetic pole portion 7 is on the N pole side, and the other magnetic pole portion 7 is on the S pole side. The magnetic repulsion and attraction of the magnetic pole portion 7 and the corresponding magnetic pole on the inner surface side of the permanent magnet 2 cause the shaft 1 to perform a reciprocating rotation at a predetermined angle. In this case, a current was applied to the coil 4. The magnetic relationship of repulsion and attraction between the magnetic poles of one magnetic pole part 7 spaced apart in the axial direction at the time and the corresponding magnetic poles on the inner surface side of the permanent magnet 2 and the other magnetic poles spaced apart in the axial direction The positions of the magnetic poles 7 on the both sides in the axial direction around the axis such that the magnetic relationship of repulsion and attraction between the magnetic poles of the magnetic poles 7 and the corresponding magnetic poles on the inner surface side of the permanent magnet 2 are the same. By setting the positional relationship between the inner surface of the permanent magnet 2 and the magnetic poles, the mover 3 is highly efficient, It is capable of performing a reciprocating rotary drive torque. Permanent magnets 2 are provided on both sides of the coil 4 in the axial direction. The permanent magnets 2 are magnetized in a direction crossing the axial direction of the shaft 1, and the magnetic pole portions 7 are spaced apart in the axial direction of the shaft 1. The magnetic pole portion 7 is interposed between the coil 4 and the mover 3 because it protrudes from the shaft 1 so as to oppose the permanent magnets 2 provided on both sides of the coil 4 in the axial direction from the separated positions. Therefore, the diameter of the actuator can be reduced as compared with the conventional example in which the coil 4 is arranged on the outer periphery of the magnetic pole teeth (that is, the magnetic pole teeth are located between the inner periphery of the coil 4 and the outer periphery of the mover 3). Also, the magnetic pole portion 7 can be opposed to the permanent magnets 2 provided on both sides of the coil 4 in the axial direction from positions spaced apart in the axial direction of the shaft 1 respectively. Or one shaft Because are projected, it is possible to generate a large torque is 2.45 large facing area which force is generated by the far from the shaft 1. Then, for example, by using the actuator of the present invention as a drive unit of the electric toothbrush, the diameter of the grip unit that houses the actuator of the electric toothbrush can be reduced, and usability can be improved.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described with reference to the accompanying drawings.
[0020]
1 to 4 show one embodiment of the present invention.
The actuator includes a movable element 3 rotatably supported around an axis, and a cylindrical stator 6 through which the movable element 3 is rotatably inserted around the axis.
[0021]
As shown in FIG. 1, a cylindrical stator 6 is provided inside a shield case 9 made of a magnetic material having a cylindrical shape (in the embodiment, cylindrical shape). The stator 6 winds the coil 4 around the coil bobbin 10 and has a cylindrical yoke 5 (yoke 5a, yoke 5b) having an inner diameter smaller than that of the coil bobbin 10 on both sides of the coil bobbin 10. , 5b are magnetically connected by a magnetic body 11, and a plurality of magnetic pole portions 7 project from the inner peripheral portions of the yokes 5a, 5b on both sides toward the mover 3 side.
[0022]
Here, in the embodiment shown in FIG. 1, the yokes 5a and 5b arranged on both sides of the coil 4 are magnetically connected by separate cylindrical magnetic bodies 11, and the yokes 5a and 5b on both sides and the magnetic bodies 11 are connected. And the two yokes 5a and 5b are magnetically connected by a shield case 9 made of a magnetic material, and the two yokes 5a and 5b and the shield case 9 form one yoke body. Alternatively, the yokes 5a and 5b on both sides and the magnetic body 11 may be integrated to form an integrated yoke body.
[0023]
In the embodiment shown in FIGS. 1 to 3, two magnetic pole portions 7 protrude from the inner peripheral portions of the yokes 5 a and 5 b arranged on both sides of the coil 4, and two magnetic pole portions 7 provided on one yoke 5 a are provided. The magnetic pole portions 7 are located 180 ° apart in the direction around the axis of the cylindrical stator 6, and the two magnetic pole portions 7 provided on the other yoke 5 b are arranged in the direction around the axis of the cylindrical stator 6. In addition, the magnetic pole portion 7 provided on one yoke 5a and the magnetic pole portion 7 provided on the other yoke 5b are shifted from each other in the direction around the axis of the cylindrical stator 6. In the present embodiment, an example is shown in which the magnetic pole portion 7 provided on one yoke 5a and the magnetic pole portion 7 provided on the other yoke 5b are shifted by 90 ° in the direction around the axis of the cylindrical stator 6. .
[0024]
The mover 3 is configured by providing the permanent magnet 2 on the outer periphery of the shaft 1. Here, in the present invention, the shaft 1 provided with the permanent magnet 2 is made of a magnetic material for the purpose of reducing magnetic resistance, increasing the amount of magnetic flux, increasing torque, and enabling high-efficiency, high-torque rotation drive. It is composed. The movable element 3 rotatably holds the shaft 1 on bearings 12 provided at both axial ends of a cylindrical shield case 9 so that the movable element 3 can freely rotate in the rotation direction. The shield 6 is inserted through the stator 6 with a predetermined gap therebetween. Further, the mover 1 is connected on both sides in the axial direction of a portion where the permanent magnet 2 is provided by an elastic body 13 such as a spring, so that the mover 3 and the elastic body 13 perform reciprocating rotational movement about the shaft 1. It constitutes a vibration system.
[0025]
A plurality of permanent magnets 2 are provided around the axis of the shaft 1, and each of the plurality of permanent magnets 2 has a different outer surface and inner surface in a direction intersecting the axial direction of the shaft 1 as shown in FIGS. 2 and 3. The magnetic poles on the outer surface of the permanent magnet 2 adjacent to each other in the direction around the axis have different polarities. That is, the N pole and the S pole are alternately magnetized in the direction around the axis. In the embodiment shown in FIGS. 2 and 3, four permanent magnets 2 are provided on the outer periphery of the shaft 1 in the direction around the axis, and the four permanent magnets 2 have N poles and S poles whose magnetic poles on the outer surface are alternately arranged. It is magnetized so that
[0026]
Here, the relationship between the magnetic pole portions 7 provided on both yokes 5a and 5b and the magnetic poles on the outer surface of the permanent magnet 2 facing these magnetic pole portions 7 is set as follows. That is, when an electric current is applied to the coil 4, the magnetic repulsion and attraction between the magnetic pole of the magnetic pole portion 7 provided on one yoke 5 a and the magnetic pole on the outer surface side of the permanent magnet 2 of the mover 3 opposed to the yoke 5 a. The magnetic relationship of repulsion and attraction between the mover, the magnetic pole of the magnetic pole portion 7 provided on the other yoke 5b, and the magnetic pole on the outer surface side of the permanent magnet 2 of the mover 3 facing the mover is the same. Thus, the positional relationship between the positions of the magnetic pole portions 7 provided on the yokes 5a and 5b on both sides in the direction around the axis and the magnetic poles on the outer surface of the permanent magnet 2 is set. That is, the magnetic pole of the magnetic pole portion 7 provided on one yoke 5a and the magnetic pole on the outer surface side of the permanent magnet 2 of the movable element 3 opposed thereto rotate the movable element 3 around the axis by a magnetic relationship of repulsion and attraction. When torque is generated, the movable element 3 is moved by the magnetic relationship of repulsion and attraction between the magnetic pole of the magnetic pole portion 7 provided on the other yoke 5b and the magnetic pole on the outer surface side of the permanent magnet 2 of the movable element 3 facing the magnetic pole. The magnetic relationship between the magnetic pole portions 7 provided on the yokes 5b on both sides and the permanent magnets 2 opposed to the magnetic pole portions 7 is set so as to generate torque for rotating in the same direction as described above.
[0027]
Next, the operation principle will be described with reference to FIG. When a current flows in the coil 4 in one direction, different poles are generated between the magnetic pole portion 7 provided on one yoke 5a in the axial direction of the coil 4 and the magnetic pole portion 7 provided on the other yoke 5b in the axial direction of the coil 4. I do. For example, as shown in FIG. 3, if a magnetic pole portion 7 provided on one yoke 5a in the axial direction has an N pole and a magnetic pole portion 7 provided on a yoke 5b located on the other side has an S pole, As shown in FIGS. 3A and 3B, clockwise torques are generated between the magnetic pole portions 7 provided on the yokes 5a and 5b on both sides of the coil 4 and the permanent magnet 2 of the mover 3, respectively. Then, the mover 3 rotates clockwise. When a current in the other direction is supplied to the coil 4, the magnetic pole part 7 provided on one yoke 5 a in the axial direction of the coil 4 is different from the magnetic pole part 7 provided on the other yoke 5 b in the axial direction of the coil 4. Is generated between the magnetic pole portions 7 provided on both yokes 5a and 5b on both sides of the coil 4 and the permanent magnets 2 of the mover 3, respectively. 3 rotates counterclockwise. Therefore, by passing an alternating current through the coil 4, the mover 3 can be reciprocated at a predetermined angle about the shaft. FIG. 4 shows the torque characteristics. When the state shown in FIG. 3 is set to an angle of 0 °, current is not flowing at ± 45 °, current is flowing in one direction, and current is flowing in the other direction. The torque per unit current at the position of the angle 0 ° is the largest. Then, a predetermined angle at which the reciprocating rotation of the mover 3 in the present invention is set within a range indicated by M in FIG.
[0028]
By the way, as described above, the magnetic pole portions 7 are protruded from the inner circumferences of the yokes 5a and 5b provided on both sides in the axial direction of the coil 4 toward the mover 3 so as to face the permanent magnets 2 respectively. Therefore, the magnetic pole portion 7 is configured not to be interposed between the coil 4 and the mover 3. With this configuration, the diameter of the actuator can be reduced as compared with the conventional example in which the magnetic pole teeth serving as the magnetic poles are arranged between the coil 4 and the permanent magnet of the mover 3 already described. Therefore, the diameter and size of the actuator can be reduced, and various electric devices using the actuator, for example, when the actuator of the present invention is installed in the grip of the electric toothbrush and used as a drive source of the electric toothbrush, the diameter of the grip is small. Can be reduced, and the usability as an electric toothbrush is improved.
[0029]
Next, another embodiment of the present invention will be described with reference to FIGS. The basic configuration of the present embodiment is the same as that of the above-described embodiment shown in FIGS. 1 to 4, and thus a duplicate description will be omitted, and different configurations will be described.
[0030]
In the present embodiment, yokes 5a and 5b are arranged on both sides of the coil 4, and a plurality of magnetic poles 7 protrude from the inner peripheral portions of the yokes 5a and 5b on both sides toward the mover 3 side. 6. Here, in this embodiment, the magnetic pole portion 7 provided on one yoke 5a and the magnetic pole portion 7 provided on the other yoke 5b are made to coincide with each other in the direction around the axis. As shown in FIGS. 6 (a) and 6 (b), a plurality of magnetic pole portions 7 are protruded from the inner periphery of one yoke 5a (in the embodiment, four magnetic pole portions 7 are 90 ° around the axis). And the same number of magnetic pole portions 7 protruding from the inner periphery of the other yoke 5b to the one yoke 5a are provided (in the embodiment, in the embodiment). The four magnetic pole portions 7 protrude at an interval of 90 ° around the axis), and a plurality of magnetic pole portions 7 shown in FIG. 6A and a plurality of magnetic pole portions 7 shown in FIG. And in the direction around the axis.
[0031]
The mover 3 is configured by providing a permanent magnet 2 on the outer periphery of a shaft 1 made of a magnetic material. In the present embodiment, as shown in FIGS. 5 and 6, a plurality (eight in the embodiment) of permanent magnets are arranged around the shaft 1 at the outer peripheral portion of the shaft 1 facing the magnetic pole portion 7 protruding from one yoke 5a. A plurality of permanent magnets (eight in the embodiment) other than the above are provided in the outer circumferential portion of the shaft 1 facing the magnetic pole portion 7 protruding from the other yoke 5b in the axial direction. 2 are provided. All the permanent magnets 2 are magnetized such that the outer surface and the inner surface in a direction intersecting the axial direction of the shaft 1 have different polarities as shown in FIG. 5 and FIG. The plurality of permanent magnets 2 opposed to the magnetic pole portions 7 protruding from 5a are magnetized alternately with N poles and S poles such that the magnetic poles on the outer surface of the permanent magnets 2 adjacent in the axial direction have different polarities. Further, the plurality of permanent magnets 2 facing the magnetic pole portion 7 protruding from the other yoke 5b have N poles and S poles such that the magnetic poles on the outer surface of the permanent magnets 2 adjacent in the axial direction are different from each other. Are alternately magnetized, and the magnetic poles on the outer surfaces of the permanent magnets 2 adjacent in the axial direction at different positions in the axial direction are different from each other.
[0032]
As described above, in the present embodiment, the magnetic pole portion 7 provided on one yoke 5a and the magnetic pole portion 7 provided on the other yoke 5b are aligned in the direction around the axis, and the magnetic pole portion 7 provided on one yoke 5a is If the magnetic poles on the outer surface of the corresponding permanent magnet 2 are different from the magnetic poles on the outer surface of the permanent magnet 2 corresponding to the magnetic pole portion 7 protruding from the other yoke 5b provided at a position coincident with the permanent magnet 2 around the axis. Thus, when a current flows through the coil 4, repulsion and attraction between the magnetic pole of the magnetic pole portion 7 provided on one yoke 5 a and the magnetic pole on the outer surface side of the permanent magnet 2 of the mover 3 opposed to this. And the repulsive and attractive magnetic relationship between the magnetic pole of the magnetic pole portion 7 provided on the other yoke 5b and the magnetic pole on the outer surface side of the permanent magnet 2 of the mover 3 opposed thereto is the same. It is configured as follows.
[0033]
The operation principle of the present embodiment will be described with reference to FIG. When a current flows in the coil 4 in one direction, different poles are generated between the magnetic pole portion 7 provided on one yoke 5a in the axial direction of the coil 4 and the magnetic pole portion 7 provided on the other yoke 5b in the axial direction of the coil 4. I do. For example, as shown in FIG. 6, if the magnetic pole portion 7 provided on one yoke 5a in the axial direction has an N pole and the magnetic pole portion 7 provided on the yoke 5b located on the other side has an S pole, the coil 4 As shown in FIGS. 6 (a) and 6 (b), between the magnetic pole portions 7 provided on both yokes 5a and 5b on both sides of the A torque is generated, and the mover 3 rotates clockwise. When a current in the other direction is supplied to the coil 4, the magnetic pole part 7 provided on one yoke 5 a in the axial direction of the coil 4 is different from the magnetic pole part 7 provided on the other yoke 5 b in the axial direction of the coil 4. Is generated between the magnetic pole portions 7 provided on both yokes 5a and 5b on both sides of the coil 4 and the permanent magnets 2 facing the magnetic pole portions 7, respectively, in the counterclockwise direction opposite to the above. Occurs, and the mover 3 rotates counterclockwise. Therefore, by passing an alternating current through the coil 4, the mover 3 can be reciprocated at a predetermined angle about the shaft.
[0034]
Next, still another embodiment of the present invention will be described with reference to FIGS. 7, 8, and 9. FIG. The basic configuration of the present embodiment is the same as that of the above-described embodiment shown in FIGS. 1 to 4, and thus a duplicate description will be omitted, and different configurations will be described.
[0035]
In this embodiment, the configuration of the stator 6 is substantially the same as the embodiment shown in FIGS. 1 to 3 described above (note that in FIG. 9, the stator 6 extends from the inner periphery of the yokes 5a and 5b on both sides in the axial direction. 3 is different from FIG. 3 in that four magnetic pole portions 7 are provided at intervals of 90 °, but the number of magnetic pole portions 7 is not limited in the present embodiment.)
[0036]
In the present embodiment, the mover 3 has a magnetic member 8 made of a magnetic material attached to an outer peripheral portion of the shaft 1 made of a magnetic material, and a predetermined interval in the circumferential direction on the outer peripheral surface of the magnetic member 8 (see FIGS. The permanent magnets 2 are embedded at 90 ° intervals.
[0037]
That is, permanent magnets 2 made of flat bar magnets are embedded in concave portions 15 provided at four circumferential positions of a cylindrical magnetic member 8 fitted and fixed to the shaft 1. On the outer surface of the mover 3, the outer surface of the permanent magnet 2 and the outer surface of the magnetic member 8 are alternately positioned in the direction around the axis, and the outer surface of the permanent magnet 2 in the direction intersecting with the shaft 1. The magnets are magnetized so that their poles are different from each other, and the outer faces of all the permanent magnets 2 have the same pole.
[0038]
Also in the present embodiment, the relationship between the magnetic pole portions 7 provided on both yokes 5a and 5b and the magnetic poles on the outer surface of the permanent magnet 2 facing these magnetic pole portions 7 is the same as in the embodiment shown in FIGS. Similarly, when the magnetic pole portions 7 provided on both yokes 5a and 5b provided on both sides in the axial direction of the coil 4 are shifted in the direction around the axis, when a current flows through the coil 4, one of the yokes 5a and 5b is turned off. The magnetic relationship of repulsion and attraction between the magnetic pole of the magnetic pole portion 7 provided on the yoke 5a and the magnetic pole on the outer surface side of the permanent magnet 2 of the mover 3 facing the yoke 5a, and the magnetic pole portion 7 provided on the other yoke 5b And the magnetic pole of repulsion and attraction between the magnetic pole on the outer surface side of the permanent magnet 2 of the mover 3 and the magnetic pole opposite thereto are the same.
[0039]
The operation principle of the present embodiment will be described with reference to FIG. When a current flows in the coil 4 in one direction, different poles are generated between the magnetic pole portion 7 provided on one yoke 5a in the axial direction of the coil 4 and the magnetic pole portion 7 provided on the other yoke 5b in the axial direction of the coil 4. I do. For example, as shown in FIG. 9, if an N pole is generated in the magnetic pole portion 7 provided on one yoke 5a in the axial direction, and an S pole is generated in the magnetic pole portion 7 provided on the yoke 5b located on the other side. As shown in FIGS. 9A and 9B, clockwise torques are generated between the magnetic pole portions 7 provided on the yokes 5a and 5b on both sides of the coil 4 and the permanent magnet 2 of the mover 3, respectively. Then, the mover 3 rotates clockwise. When a current in the other direction is supplied to the coil 4, the magnetic pole part 7 provided on one yoke 5 a in the axial direction of the coil 4 is different from the magnetic pole part 7 provided on the other yoke 5 b in the axial direction of the coil 4. Is generated between the magnetic pole portions 7 provided on both yokes 5a and 5b on both sides of the coil 4 and the permanent magnets 2 of the mover 3, respectively. 3 rotates counterclockwise. Therefore, by passing an alternating current through the coil 4, the mover 3 can be reciprocated at a predetermined angle about the shaft.
[0040]
In the present embodiment as described above, the outer surface of the magnetic member 8 adjacent to the permanent magnet 2 in the direction around the axis becomes a magnetic pole different from the magnetic pole of the outer surface of the permanent magnet 2 and functions as a magnet to be different around the axis. The presence of the magnetic poles makes it possible to reduce the number of expensive permanent magnets 2 used in comparison with the above-described embodiments, thereby realizing a low-cost actuator. The observed magnetoresistance can be reduced.
[0041]
Next, still another embodiment of the present invention will be described with reference to FIGS.
[0042]
In each of the above embodiments, the permanent magnet 2 is provided on the mover 3 side, and the magnetic pole portion 7 is provided on the stator 6 side. However, in the present embodiment, the permanent magnet 2 is provided on the stator 6 side, and the magnetic pole portion 7 is provided. Is provided on the shaft 1 side made of a magnetic material, which is different from the above embodiments.
[0043]
That is, the stator 6 is configured by disposing the permanent magnets 2 in a cylindrical shape on both sides of the coil 4 in the axial direction. More specifically, as shown in FIGS. 10 and 11, a plurality of (four in the embodiment) permanent magnets 2 each having an arc-shaped cross section are arranged side by side in the axial direction on both sides of the coil 4 in the axial direction. Both cylindrical magnets have an inner diameter larger than the inner diameter of the coil 4 (actually, not shown, but the inner diameter of the coil bobbin). All the permanent magnets 2 are magnetized such that the inner surface and the outer surface in the direction intersecting the axis have different polarities. In addition, the plurality of permanent magnets 2 arranged in parallel in the axial direction on one side of both sides in the axial direction of the coil 4 have magnetic poles on the inner surface of the permanent magnets 2 adjacent in the axial direction as shown in FIG. Is different. Further, the plurality of permanent magnets 2 arranged side by side in the axial direction on the other side of both sides in the axial direction of the coil 4 have the inner surface magnetic poles of the permanent magnets 2 adjacent in the axial direction as shown in FIG. Is different. In the embodiment shown in FIGS. 10 and 11, a plurality of permanent magnets 2 are arranged side by side in the axial direction on one side of the coil 4 in the axial direction, and are arranged side by side on the other side in the axial direction of the coil 4 in the axial direction. The plurality of permanent magnets 2 have the same magnetic pole on the inner surface side of the permanent magnets 2 that match in the axial direction.
[0044]
A magnetic pole portion 7 is provided so as to protrude from a position spaced apart in the axial direction of the shaft 1 made of a magnetic material so as to respectively face the permanent magnets 2 provided on both sides of the coil 4 in the axial direction. As shown in FIG. 11 (a), two magnetic pole portions intersecting with the axial direction corresponding to a cylindrical magnet made up of a plurality of permanent magnets 2 arranged side by side in the axial direction on one side of the coil 4 in the axial direction. 7 projecting in the direction around the axis at an interval of 180 °, and as shown in FIG. 11B, a plurality of permanent magnets juxtaposed in the direction around the axis on the other side in the axial direction of the coil 4. Two magnetic pole portions 7 intersecting with the axial direction corresponding to the cylindrical magnets made of the magnets 2 are protruded at intervals of 180 ° in the direction around the axis, and furthermore, the magnetic pole portions shown in FIG. 7 and the magnetic pole part 7 shown in FIG. . With such a configuration, when a current is applied to the coil 4, repulsion between the magnetic poles of the one magnetic pole portion 7 spaced apart in the axial direction and the corresponding magnetic poles on the inner surface side of the permanent magnet 2, The magnetic relationship between the attraction and the repulsion and attraction between the magnetic pole of the other magnetic pole portion 7 spaced apart in the axial direction and the corresponding magnetic pole on the inner surface side of the permanent magnet 2 are the same. It is.
[0045]
The operation principle of the present embodiment will be described with reference to FIG. When a current in one direction is applied to the coil 4, the magnetic pole portion 7, which is opposed to one of the permanent magnets 2, is disposed on both sides of the coil 4 in the axial direction. A different pole is generated in the magnetic pole portion 7 of the permanent magnet 2 facing the other permanent magnet 2. For example, if an N pole is generated in the magnetic pole portion 7 of FIG. 11A and an S pole is generated in the magnetic pole portion 7 of FIG. 11B located on the other side, the two permanent magnets 2 on both sides of the coil 4 are provided. 11 (a) and 11 (b), a clockwise torque is generated between the magnetic pole portions 7 facing the permanent magnet 2 and the permanent magnet 2, and the mover 3 rotates clockwise. When a current in the other direction is applied to the coil 4, opposite poles are generated in the magnetic pole portions 7 on both sides, and a counterclockwise torque opposite to the arrows in FIGS. 11A and 11B is generated. Occurs, and the mover 3 rotates counterclockwise. Therefore, by passing an alternating current through the coil 4, the mover 3 can be reciprocated at a predetermined angle about the shaft.
[0046]
In the present embodiment, the permanent magnets 2 are provided on both sides in the axial direction of the coil 4, the permanent magnets 2 are magnetized in a direction intersecting with the axial direction of the shaft 1, and the magnetic pole portions 7 are spaced apart in the axial direction of the shaft 1. Are protruded from the shaft 1 so as to face the permanent magnets 2 provided on both sides of the coil 4 in the axial direction, respectively, so that the magnetic pole portion 7 is not interposed between the coil 4 and the mover 3. It has a configuration. With this configuration, the diameter of the actuator can be reduced as compared with the conventional example in which the magnetic pole teeth serving as the magnetic poles are arranged between the coil 4 and the permanent magnet of the mover 3 already described, and therefore, the diameter and size of the actuator are reduced. Can be achieved. Further, since the magnetic pole portions 7 project from the shaft 1 so as to face the permanent magnets 2 provided on both sides of the coil 4 in the axial direction from positions spaced apart in the axial direction of the shaft 1, respectively, A large opposing area where a force is generated at a location far from 1 can generate a large torque.
[0047]
And, when various electric devices using the actuator of the present embodiment, for example, the actuator of the present invention is installed in a grip portion of the electric toothbrush and used as a drive source of the electric toothbrush, the diameter of the grip portion can be reduced, and This makes it easier to use as a toothbrush.
[0048]
The magnetic relationship between the magnetic pole portion 7 and the permanent magnet 2 on one side in the axial direction and the magnetic relationship between the magnetic pole portion 7 and the permanent magnet 2 on the other side in the axial direction are determined by the magnetic pole portion 7 on one side in the axial direction. Between the magnetic pole portion 7 and the permanent magnet 2 on the other side in the axial direction. Also, even in the case where one of the torques rotating in one direction or the opposite direction is large and the other is small, it is possible to perform the reciprocating rotation by rotating in the direction in which the large torque is generated. .
[0049]
【The invention's effect】
As described above, in the vibration type actuator of the present invention, the magnetic pole portion is not interposed between the coil and the mover, and the magnetic pole tooth portion is located between the inner periphery of the coil and the outer periphery of the mover as in the related art. The actuator can be made smaller in diameter and smaller in size than the actuator, and the reciprocating rotary drive of the mover can be performed with high efficiency and high torque.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing the overall structure of an actuator according to the present invention.
FIG. 2 is a perspective view in which a main part of the actuator is cut away in a direction parallel to an axial direction.
FIGS. 3A and 3B are explanatory views for explaining the operation principle of the first embodiment; FIG. 3A is a cross-sectional view illustrating a relationship between a magnetic pole portion provided on one yoke and a permanent magnet of a mover; It is sectional drawing which shows the relationship between the magnetic pole part provided in the yoke and the permanent magnet of a mover.
FIG. 4 is a graph showing torque characteristics of the above.
FIG. 5 is a perspective view of a main part of an actuator according to another embodiment of the same, cut away in a direction parallel to an axial direction.
FIGS. 6A and 6B are explanatory views for explaining the operation principle of the first embodiment; FIG. 6A is a cross-sectional view showing a relationship between a magnetic pole portion provided on one yoke and a permanent magnet of a mover; It is sectional drawing which shows the relationship between the magnetic pole part provided in the yoke and the permanent magnet of a mover.
FIG. 7 is a cross-sectional view showing the overall structure of an actuator according to still another embodiment of the present invention.
FIG. 8 is a perspective view of a main part of an actuator according to another embodiment of the same, cut away in a direction parallel to an axial direction.
FIGS. 9A and 9B are explanatory views for explaining the operation principle of the first embodiment, in which FIG. 9A is a cross-sectional view showing a relationship between a magnetic pole portion provided on one yoke and a permanent magnet of a mover, and FIG. It is sectional drawing which shows the relationship between the magnetic pole part provided in the yoke and the permanent magnet of a mover.
FIG. 10 is a perspective view of a main part of an actuator according to still another embodiment of the above, cut away in a direction parallel to an axial direction.
11A and 11B are explanatory views for explaining the operation principle of the first embodiment, in which FIG. 11A is a cross-sectional view showing a relationship between a magnetic pole portion provided on one yoke and a permanent magnet of a mover, and FIG. It is sectional drawing which shows the relationship between the magnetic pole part provided in the yoke and the permanent magnet of a mover.
[Explanation of symbols]
1 shaft
2 permanent magnet
3 mover
4 coils
5 York
6 Stator
7 Magnetic pole
8 Magnetic material

Claims

A mover having a permanent magnet provided on a shaft is rotatably supported in a stator having a coil wound in the circumferential direction so as to surround the mover and a yoke made of a cylindrical magnetic material. An actuator in which a current is applied to a coil to cause a mover to reciprocate at a predetermined angle about a shaft, wherein the permanent magnet is magnetized in a direction intersecting the axial direction of the shaft. The yokes are provided on both sides in the axial direction of the coil, and have magnetic pole portions projecting from the inner peripheral surfaces of the yokes on both sides in the axial direction toward the mover side so as to face the permanent magnets, respectively, and apply a current to the coil. The magnetic relationship of repulsion and attraction between the magnetic pole of the magnetic pole portion provided on one yoke and the corresponding magnetic pole on the outer surface side of the permanent magnet, and the magnetic pole of the magnetic pole portion provided on the other yoke, Corresponding to the outside of the permanent magnet The position of the magnetic pole portions provided on the yokes on both sides in the direction around the axis and the positional relationship with the magnetic poles on the outer surface of the permanent magnet are set so that the magnetic relationship of repulsion and attraction with the magnetic poles on the side is the same. An actuator, characterized in that:

The actuator according to claim 1, wherein the shaft is made of a magnetic material.

3. The actuator according to claim 1, wherein magnetic pole portions provided on both yokes provided on both sides in the axial direction of the coil are shifted in a direction around the shaft about the shaft.

The magnetic pole portion provided on one yoke and the magnetic pole portion provided on the other yoke coincide in the direction around the axis, and the magnetic poles on the outer surface of the permanent magnet corresponding to the magnetic pole portion provided on the one yoke; 3. The actuator according to claim 1, wherein the magnetic poles on the outer surface of the permanent magnet corresponding to the magnetic pole portions protruding from the other yoke provided at the same position around the periphery have different magnetisms.

The magnetic material and the permanent magnet are provided on the outer peripheral portion of the shaft, and the outer surface of the magnetic material and the outer surface of the permanent magnet are arranged side by side in the direction around the axis. An actuator according to any one of the above.

A mover having a magnetic pole portion provided on a shaft is rotatably supported in a stator having a coil and a permanent magnet wound in a circumferential direction so as to surround the mover, and a current is supplied to the coil. An actuator in which the permanent magnet is provided on both sides in the axial direction of the coil, and the permanent magnet intersects with the axial direction of the shaft. The magnetic pole portions are provided from the shaft so as to be opposed to the permanent magnets provided on both sides of the coil in the axial direction, respectively, from positions spaced apart in the axial direction of the shaft, and the magnetic poles are supplied with current through the coil. The magnetic relationship of repulsion and attraction between the magnetic pole of one magnetic pole part spaced apart in the axial direction when applying the magnetic pole and the corresponding magnetic pole on the inner surface side of the permanent magnet, and the other magnetic pole part separated in the axial direction Magnetic pole The position of the magnetic poles on both sides in the axial direction around the axis and the inner surface of the permanent magnet so that the magnetic relationship between the magnetic pole and the corresponding magnetic pole on the inner surface side of the permanent magnet is the same as the magnetic relationship of repulsion and attraction. An actuator characterized by setting a positional relationship with a magnetic pole.