JP3851012B2

JP3851012B2 - Linear vibration motor

Info

Publication number: JP3851012B2
Application number: JP04303299A
Authority: JP
Inventors: 哲司植田
Original assignee: Sanyo Electric Co Ltd
Current assignee: Sanyo Electric Co Ltd
Priority date: 1999-02-22
Filing date: 1999-02-22
Publication date: 2006-11-29
Anticipated expiration: 2019-02-22
Also published as: JP2000245126A

Description

【０００１】
【産業上の利用分野】
この発明はリニア振動モータに関し、特にたとえばコイルを有する固定子鉄心の磁気空隙に軸方向に変位可能な可動体を配置したリニア振動モータに関する。
【０００２】
【従来の技術】
例えば、従来の可動鉄心（ＭＩ）型リニア振動モータ１は図６の（ａ）および（ｂ）に示す様に、円筒状の固定子積層鉄心２の内面に形成された４個の突極部２ａ、２ｂ、２ｃおよび２ｄに夫々コイル３を巻装すると共に、各突極部の端面に断面が円弧状の永久磁石４、…を装着し、これらの永久磁石４、…に囲まれた磁気空隙５に中心にシャフト６を有する可動鉄心体７を軸方向に変位可能に配置して構成される。そして、各永久磁石４は複数に分割されかつ隣り合う各磁石４ａ，４ｂ、４ｃおよび４ｄは径方向に逆向きに磁化されて配列している。
【０００３】
このように構成されたリニア振動モータ１において、コイル３に通電する電流を変化させるとことで電流による磁束と永久磁石４による磁束からなる総磁束が変化し、可動鉄心体７は磁気空隙５を通る磁束の多い方向に引き付けられて移動する。したがって、コイル３に交流電流を通電することにより、可動鉄心体７を連続的に往復動させることができる。
【０００４】
【発明が解決しようとする課題】
しかしながら、固定子積層鉄心の内面側にコイルを巻回する突極部が形成されているために、この突極部に対するコイルの巻装作業がやり難く、コスト的にも高くなるという問題がある。
それゆえに、この発明の主たる目的は、固定子鉄心の製作が簡単で量産性に富み、しかも効率の良いリニア振動モータを提供することである。
【０００５】
【課題を解決するための手段】
この発明は、コイルを有する固定子鉄心の磁気空隙に可動鉄心体を軸方向に変位可能に配置したリニア振動モータにおいて、固定鉄心は所定間隔で永久磁石を内面に装着した筒状の外側コア、および外向きに形成された突極部にコイルを巻装すると共にコイル間の外面に永久磁石を装着した柱状の内側コアとを備え、内側コアの永久磁石が外側コアの永久磁石と相対向して磁気空隙を形成するように内側コアを外側コアに挿入配置したことを特徴とする、リニア振動モータである。
【０００６】
また、この発明は、コイルを有する固定子鉄心の磁気空隙に可動磁石体を軸方向に変位可能に配置したリニア振動モータにおいて、固定鉄心は筒状の外側コア、および外向きに形成された突極部にコイルを巻装した柱状の内側コアとを備え、磁気空隙を形成するように内側コアを外側コアに挿入配置し、外側コアの内面には少なくともコイルの端部を収容する軸方向の凹所を備えることを特徴とする、リニア振動モータである。
【０００７】
【作用】
固定子鉄心は、突極部にコイルを巻装した柱状の内側コアを筒状の外側コアに挿入配置して磁気空隙を確保するようにしたから、例えば内側コアに外向きに形成された突極部に対するコイルの巻装および磁気空隙を形成する内外コアに対する永久磁石の装着が容易になる。
【０００８】
【発明の効果】
この発明によれば、コイルを有する固定子鉄心の製作が簡単で量産性に富んだリニア振動モータを提供することができる。また、コイルの占績率を高めることが可能となりモータ効率も向上する。
この発明の上述の目的，その他の目的，特徴および利点は、図面を参照して行う以下の実施例の詳細な説明により一層明らかとなろう。
【０００９】
【実施例】
この発明の一実施例であるリニア振動モータを図１〜図５に基づいて説明する。
図１の（ａ）および（ｂ）に示される可動鉄心（ＭＩ）型リニア振動モータ１０は、コイル１２を装着した固定子鉄心１４、この固定子鉄心１４の磁気空隙１６に配置され軸方向に変位可能な可動鉄心体１８を含む。
【００１０】
固定鉄心１４は、内面に断面略コ字状の溝部２０を９０°の間隔で軸方向に４個形成した円筒状の外側積層コア２２、この外側積層コア２２の内部空間に挿入配置されて磁気空隙１６を形成する柱状の内側積層コア２４の２分割体により構成される。この内側積層コア２４は外側積層コア２２の溝部２０に対向して外向きに形成された４個の突極部２６を有し、各突極部２６に夫々ループ状に巻回されたコイル１２を装着すると共に中心にシャフト挿通孔２８を設けている。
【００１１】
外側積層コア２２および内側積層コア２４は、いずれも打ち抜きにより形成された所定形状の磁性鉄板、例えば珪素鋼板を積層固定して構成される。また、外側積層コア２２の溝部２０を除く内面および内側積層コア２４のコイル間の外面には断面が円弧状に形成された永久磁石３０、…および３２、…を接着剤等により固定されている。そして、これらの永久磁石３０、３２およびコイル１２により磁気空隙１６を包囲している。
【００１２】
各永久磁石３０および３２はいずれも２分割された磁石３０ａと３０ｂおよび磁石３２ａと３２ｂを突き合わせて構成すると共に隣り合う磁石３０ａと３０ｂおよび磁石３２ａと３２ｂは径方向に対して逆向きに磁化されている。
また、固定子鉄心１４の磁気空隙１６を変位する可動鉄心体１８は有底円筒状の可動保持体３４、この可動保持体３４の底部に突設されて固定子鉄心１４の内側積層コア２４の中心に設けられるシャフト挿通孔２８を貫通するシャフト３６および可動保持体３４の開口周縁に形成した４個の保持片３８、…に内蔵保持されて固定子鉄心１４の磁気空隙１６を移動する４個の円弧状の可動鉄心４０、…を含む。
【００１３】
この固定子鉄心１４を組み立てにより製作する場合は図２に示されるように、まず、各突極部２６にコイル１２を巻装すると共にコイル間の外面に永久磁石３２を接着固定した内側積層コア２４と、溝部２０を除く内面に永久磁石３０を接着固定した外側積層コア２２を準備する。次に内側積層コア２４のコイル１２を装着した各突極部２６を外側積層コア２２の各溝部２０に案内されるように内側積層コア２４を外側積層コア２２の内部空間に挿入配置する。そして、内側積層コア２４の各突極部２６と外側積層コア２２の各溝部２０の両端に位置する接合部を例えばレーザー溶接により固定する。なお、固定子鉄心１４を組み立てる場合、上述とは逆の手順で内側積層コア２４に外側積層コア２２を嵌め込む様にしてもよい。
【００１４】
上述の構成におけるＭＩ型リニア振動モータ１０の動作について説明する。
まず、固定子鉄心１４の各コイル１２に図１の（ａ）に示すように突極部２６を周回する方向に電流を通電すると、固定子鉄心１４には図示実線矢印の方向に磁束の流れが生じる。一方、この磁束の流れにより固定子鉄心１４の外側積層コア２２の内面と内側積層コア２４の外面に夫々装着されている永久磁石３０および３２の各磁石３０ａと３０ｂおよび各磁石３２ａと３２ｂのうち、図１の（ｂ）において各左側の磁石３０ａと３２ａの磁束が強められ、各右側の磁石３０ｂと３２ｂの磁束が弱められるので、可動鉄心体１８の可動鉄心４０と４０は左方向の推力を受けて矢印左側に移動する。
【００１５】
次にコイル１２に通電する電流の方向を変えると、固定子鉄心１４を流れる磁束の方向は逆転し、その結果、固定子鉄心１４の外側積層コア２２と内側積層コア２４に夫々装着されている永久磁石３０および３２の各磁石３０ａと３０ｂおよび各磁石３２ａと３２ｂのうち、右側の磁石３０ｂと３２ｂの磁束が強められるので、可動鉄心体１８の可動鉄心４０と４０は右方向の推力を受けて矢印右側に移動する。
【００１６】
従って、固定子鉄心１４のコイル１２に交流電流を通電することにより、可動鉄心体１８は連続的に往復動するから、例えば可動鉄心体１８のシャフト３６にピストンを連結して空気や冷媒を圧縮する往復動式圧縮機を駆動できる。
図３に示す他の実施例のＭＩ型リニア振動モータ１０は、固定子鉄心１４を構成する永久磁石３０と３０を内面に装着した外側積層コア２２を円筒状に形成すると共に、この円筒状外側積層コア２２の内部空間に挿入配置される一つのコイル１２と永久磁石３２と３２を外面に装着した内側積層コア２４を円柱状に形成したものである。また、各永久磁石３０および３２は、図１の実施例と同様に磁石３０ａと３０ｂおよび磁石３２ａと３２ｂに夫々分割されて径方向に対して逆向きに磁化されている。
【００１７】
そして、円筒状の外側積層コア２２と円柱状の内側積層コア２４の間に形成される円筒状の磁気空隙１６には軸方向に変位する可動鉄心体１８が配置される。この可動鉄心体１８はシャフト３６を設けた有底円筒状の可動保持体３４、この保持体３４の円筒部に内蔵されるリング状磁性鋼板を積層して形成された可動鉄心４０を含む。この場合には可動保持体３４を合成樹脂材による一体成型で構成できる。そして、成型時に可動鉄心４０を合成樹脂材に埋設される。
【００１８】
この実施例においては、可動鉄心体１８が円筒状に形成されるので構成が簡単となり、また、内側積層コア２４に巻装されるコイル１２も一つですむから、製作がさらに簡易で量産性に富む。なお、動作原理は図１の実施例と同様につきその説明は省略する。
次に、図４に示す可動磁石（ＭＭ）型リニア振動モータの実施例について説明する。なお、図１に示すＭＩ型リニア振動モータと比較すると、永久磁石を除く固定子鉄心の構造は同じであるから、対応する部分に同じ図番を付してその説明を省略する。
【００１９】
このリニア振動モータ１０においては、固定子鉄心１４を構成する外側積層コア２２と内側積層コア２４の間に形成される磁気空隙１６に軸方向に変位する可動磁石体４２が配置されている。この可動磁石体４２は、有底円筒状の磁石保持枠４４、この保持枠４４の底部に突設されかつ内側積層コア２４の中心に設けられているシャフト挿通孔２８を貫通するシャフト３６および磁石保持枠４４に保持される４個の永久磁石４６を含む。各永久磁石４６はいずれも磁石４６ａと４６ｂに２分割されしかも径方向に対して逆向きに磁化されている。
【００２０】
上述の構成において、固定子鉄心１４のコイル１２に図示のように紙面表側から紙面裏側の方向に電流を流すと、図１の（ａ）に示されるパターンと同様に固定子鉄心１４には図示矢印のような磁束の流れが生じる。一方、可動磁石体４２に装着されている各永久磁石４６は磁石４６ａと４６ｂに分割されて互いに逆向きに磁化されているので、固定子鉄心１４を流れる磁束により図４の（ｂ）において左側の磁石４６ａの磁束が強くなり、逆に右側の磁石４６ｂの磁束が弱くなり、可動磁石体４２は左方向の推力を受けて図示矢印の左側に移動する。そして、コイル１２に流す電流の方向を変えると、固定子鉄心１４を流れる磁束の方向が逆転し、その結果、右側の磁石４６ｂの磁束が左側の磁石４６ａの磁束より強くなり、可動磁石体４２は右方向の推力を受けて図示矢印の右側に移動する。
【００２１】
従って、この実施例においても、固定子鉄心１４のコイル１２に交流電流を通
電することにより、連続的に可動磁石体４２を往復動せしめることができる。
更に、図５の（ａ）および（ｂ）に示すＭＭ型リニア振動モータ１０の他の実施例は、図４の実施例と比較すると固定子鉄心１４を構成する外側積層コア２２を円筒状に形成すると共に、一つのコイル１２を巻装した内側積層コア２４を円柱状に形成している点が構成上相違するだけで、その他の構成は同じであるから、同じ図番を付して説明は省略する。そして、円筒状の外側積層コア２２の内部空間に同心的に円柱状の内側積層コア２４を挿入配置して両コアの間に形成される円筒状の磁気空隙１６に軸方向に変位する円筒状の可動磁石体４２を配置している。この可動磁石体４２はシャフト３６を有する有底円筒状の磁石保持枠４４の開口端側に断面円弧状に形成された一対の永久磁石４６と４６を対向保持している。そして、各永久磁石４６は軸方向で磁石４６ａと４６ｂに分割され径方向に対して逆向きに磁化されている。
【００２２】
なお、この実施例における動作原理も、図４の実施例と同様につきその説明は省略する。
【図面の簡単な説明】
【図１】（ａ）および（ｂ）はこの発明の一実施例である可動鉄心（ＭＩ）型リニア振動モータのＡ−ＡおよびＢ−Ｂに相当する図解図である。
【図２】図１に示されるＭＩ型リニア振動モータの分解斜面図である。
【図３】（ａ）および（ｂ）は図１の（ａ）および（ｂ）に相当する他の実施例を示すＭＩ型リニア振動モータの図解図である。
【図４】（ａ）および（ｂ）はこの発明の他の実施例を示す可動磁石（ＭＭ）型リニア振動モータのＡ−ＡおよびＢ−Ｂに相当する図解図である。
【図５】（ａ）および（ｂ）は図４の（ａ）および（ｂ）に相当する他の実施例を示すＭＭ型リニア振動モータの図解図である。
【図６】（ａ）および（ｂ）は図１の（ａ）およびｂ）に相当する従来例のＭＩ型リニア振動モータの図解図である。
【符号の説明】
１０ …リニア振動モータ
１２ …コイル
１４ …固定子鉄心
１６ …磁気空間
１８ …可動鉄心体
２０ …コ字状の溝部
２２ …外側積層コア
２４ …内側積層コア
２６ …突極部
３０、３２、４６ …永久磁石
３４ …可動保持体
３６ …シャフト
３８ …保持片
４０ …可動鉄心
４２ …可動磁石体
４４ …磁石保持枠[0001]
[Industrial application fields]
The present invention relates to a linear vibration motor, and more particularly to a linear vibration motor in which a movable body that can be displaced in the axial direction is arranged in a magnetic gap of a stator core having a coil.
[0002]
[Prior art]
For example, a conventional movable iron core (MI) type linear vibration motor 1 has four salient pole portions formed on the inner surface of a cylindrical stator laminated iron core 2 as shown in FIGS. 6 (a) and 6 (b). A coil 3 is wound around each of 2a, 2b, 2c, and 2d, and permanent magnets 4 are attached to the end surfaces of the salient poles, and a magnet surrounded by the permanent magnets 4 is attached. A movable iron core body 7 having a shaft 6 in the center of the gap 5 is arranged so as to be displaceable in the axial direction. Each permanent magnet 4 is divided into a plurality of magnets, and adjacent magnets 4a, 4b, 4c, and 4d are magnetized in the opposite direction in the radial direction and arranged.
[0003]
In the linear vibration motor 1 configured as described above, the total magnetic flux composed of the magnetic flux generated by the current and the magnetic flux generated by the permanent magnet 4 is changed by changing the current supplied to the coil 3. It is attracted and moved in the direction in which the passing magnetic flux is large. Therefore, the movable iron core 7 can be continuously reciprocated by energizing the coil 3 with an alternating current.
[0004]
[Problems to be solved by the invention]
However, since the salient pole part which winds a coil is formed in the inner surface side of a stator lamination iron core, winding work of the coil to this salient pole part is difficult to do, and there is a problem that it becomes expensive. .
SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide a linear vibration motor which is easy to manufacture a stator core, has a high productivity, and is efficient.
[0005]
[Means for Solving the Problems]
The present invention provides a linear vibration motor in which a movable iron core is disposed in a magnetic gap of a stator iron core having a coil so as to be axially displaceable, and the fixed iron core has a cylindrical outer core having permanent magnets mounted on the inner surface at predetermined intervals. And a columnar inner core in which a coil is wound around an outwardly formed salient pole portion and a permanent magnet is mounted on the outer surface between the coils, and the permanent magnet of the inner core is opposed to the permanent magnet of the outer core. Thus, the linear vibration motor is characterized in that the inner core is inserted into the outer core so as to form a magnetic gap.
[0006]
Further, according to the present invention, in the linear vibration motor in which the movable magnet body is disposed in the magnetic gap of the stator core having a coil so as to be axially displaceable, the fixed core has a cylindrical outer core and a protrusion formed outward. An inner core inserted into the outer core so as to form a magnetic air gap, and the inner surface of the outer core accommodates at least the end of the coil in the axial direction. A linear vibration motor including a recess .
[0007]
[Action]
Since the stator core has a columnar inner core with a coil wound around the salient pole portion inserted into the cylindrical outer core so as to secure a magnetic gap, for example, a protrusion formed outwardly on the inner core. The coil can be wound around the pole and the permanent magnet can be easily attached to the inner and outer cores forming the magnetic gap.
[0008]
【The invention's effect】
According to the present invention, it is possible to provide a linear vibration motor that is easy to manufacture a stator core having a coil and is rich in mass productivity. In addition, the coil occupancy rate can be increased, and the motor efficiency is improved.
The above object, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.
[0009]
【Example】
A linear vibration motor according to an embodiment of the present invention will be described with reference to FIGS.
A movable core (MI) type linear vibration motor 10 shown in FIGS. 1A and 1B is arranged in a stator core 14 having a coil 12 mounted thereon and a magnetic gap 16 of the stator core 14 and is arranged in the axial direction. A displaceable movable iron core 18 is included.
[0010]
The fixed iron core 14 has a cylindrical outer laminated core 22 in which four grooves 20 having a substantially U-shaped cross section are formed on the inner surface in the axial direction at intervals of 90 °, and is inserted into the inner space of the outer laminated core 22 to be magnetic. The columnar inner laminated core 24 that forms the gap 16 is composed of two divided bodies. The inner laminated core 24 has four salient pole portions 26 formed outward facing the groove portions 20 of the outer laminated core 22, and the coil 12 wound around each salient pole portion 26 in a loop shape. And a shaft insertion hole 28 is provided at the center.
[0011]
Each of the outer laminated core 22 and the inner laminated core 24 is configured by laminating and fixing a magnetic iron plate of a predetermined shape formed by punching, for example, a silicon steel plate. Further, permanent magnets 30,..., 32,... Having a cross-section formed in an arc shape are fixed to the inner surface excluding the groove portion 20 of the outer laminated core 22 and the outer surface between the coils of the inner laminated core 24 with an adhesive or the like. . The permanent magnets 30 and 32 and the coil 12 surround the magnetic gap 16.
[0012]
Each of the permanent magnets 30 and 32 is configured by abutting two magnets 30a and 30b and magnets 32a and 32b, and the adjacent magnets 30a and 30b and magnets 32a and 32b are magnetized in the opposite direction to the radial direction. ing.
A movable core 18 that displaces the magnetic gap 16 of the stator core 14 is provided with a bottomed cylindrical movable holder 34, and protrudes from the bottom of the movable holder 34 so that the inner laminated core 24 of the stator core 14 Four shafts that penetrate the shaft insertion hole 28 provided at the center and four holding pieces 38 formed on the periphery of the opening of the movable holding body 34, and that move in the magnetic gap 16 of the stator iron core 14. Arc-shaped movable iron cores 40...
[0013]
When the stator core 14 is manufactured by assembly, as shown in FIG. 2, first, the inner laminated core in which the coil 12 is wound around each salient pole portion 26 and the permanent magnet 32 is bonded and fixed to the outer surface between the coils. 24 and an outer laminated core 22 having a permanent magnet 30 bonded and fixed to the inner surface excluding the groove 20 are prepared. Next, the inner laminated core 24 is inserted and disposed in the inner space of the outer laminated core 22 so that each salient pole portion 26 to which the coil 12 of the inner laminated core 24 is attached is guided by each groove 20 of the outer laminated core 22. And the junction part located in the both ends of each salient pole part 26 of the inner side laminated core 24 and each groove part 20 of the outer side laminated core 22 is fixed by laser welding, for example. When the stator core 14 is assembled, the outer laminated core 22 may be fitted into the inner laminated core 24 in the reverse procedure to that described above.
[0014]
The operation of the MI type linear vibration motor 10 having the above configuration will be described.
First, when an electric current is applied to each coil 12 of the stator core 14 in a direction around the salient pole portion 26 as shown in FIG. 1A, a magnetic flux flows in the stator core 14 in the direction indicated by the solid line arrow. Occurs. On the other hand, among the magnets 30a and 30b of the permanent magnets 30 and 32 and the magnets 32a and 32b respectively attached to the inner surface of the outer laminated core 22 and the outer surface of the inner laminated core 24 of the stator core 14 by the flow of magnetic flux. 1 (b), the magnetic fluxes of the left magnets 30a and 32a are strengthened, and the magnetic fluxes of the right magnets 30b and 32b are weakened. Therefore, the movable iron cores 40 and 40 of the movable iron core 18 are thrust in the left direction. And move to the left side of the arrow.
[0015]
Next, when the direction of the current flowing through the coil 12 is changed, the direction of the magnetic flux flowing through the stator core 14 is reversed, and as a result, the outer core 22 and the inner core 24 of the stator core 14 are respectively mounted. Of the magnets 30a and 30b of the permanent magnets 30 and 32 and the magnets 32a and 32b, the magnetic flux of the right magnets 30b and 32b is strengthened, so that the movable iron cores 40 and 40 of the movable iron core 18 receive a thrust in the right direction. To the right of the arrow.
[0016]
Therefore, by applying an alternating current to the coil 12 of the stator core 14, the movable core 18 continuously reciprocates. For example, a piston is connected to the shaft 36 of the movable core 18 to compress air and refrigerant. The reciprocating compressor can be driven.
The MI type linear vibration motor 10 of another embodiment shown in FIG. 3 is formed with an outer laminated core 22 having a permanent magnet 30 and 30 constituting the stator core 14 mounted on the inner surface thereof in a cylindrical shape, and this cylindrical outer surface. The inner laminated core 24 having a single coil 12 and permanent magnets 32 and 32 inserted and disposed in the inner space of the laminated core 22 is formed in a cylindrical shape. Each permanent magnet 30 and 32 is divided into magnets 30a and 30b and magnets 32a and 32b, respectively, and is magnetized in the opposite direction to the radial direction, as in the embodiment of FIG.
[0017]
A movable iron core 18 that is displaced in the axial direction is disposed in a cylindrical magnetic gap 16 formed between the cylindrical outer laminated core 22 and the columnar inner laminated core 24. The movable iron core 18 includes a bottomed cylindrical movable holder 34 provided with a shaft 36, and a movable iron core 40 formed by laminating ring-shaped magnetic steel plates incorporated in the cylindrical portion of the holder 34. In this case, the movable holding body 34 can be formed by integral molding with a synthetic resin material. And the movable iron core 40 is embed | buried under a synthetic resin material at the time of shaping | molding.
[0018]
In this embodiment, since the movable iron core 18 is formed in a cylindrical shape, the configuration is simple, and since only one coil 12 is wound around the inner laminated core 24, the manufacturing is further simplified and the mass productivity is improved. Rich. The operation principle is the same as that of the embodiment of FIG.
Next, an embodiment of the movable magnet (MM) type linear vibration motor shown in FIG. 4 will be described. Compared with the MI-type linear vibration motor shown in FIG. 1, the structure of the stator core excluding the permanent magnet is the same. Therefore, the corresponding parts are denoted by the same reference numerals and the description thereof is omitted.
[0019]
In the linear vibration motor 10, a movable magnet body 42 that is displaced in the axial direction is disposed in the magnetic gap 16 formed between the outer laminated core 22 and the inner laminated core 24 that constitute the stator core 14. The movable magnet body 42 includes a bottomed cylindrical magnet holding frame 44, a shaft 36 projecting from the bottom of the holding frame 44 and penetrating through a shaft insertion hole 28 provided at the center of the inner laminated core 24. Four permanent magnets 46 held by the holding frame 44 are included. Each permanent magnet 46 is divided into two magnets 46a and 46b and is magnetized in the opposite direction to the radial direction.
[0020]
In the configuration described above, when a current is passed through the coil 12 of the stator core 14 from the front side to the back side as shown in the drawing, the stator core 14 is shown in the same manner as the pattern shown in FIG. Magnetic flux flows as shown by arrows. On the other hand, since each permanent magnet 46 mounted on the movable magnet body 42 is divided into magnets 46a and 46b and magnetized in opposite directions, the left side in FIG. On the contrary, the magnetic flux of the right magnet 46b is weakened, and the movable magnet body 42 receives the thrust in the left direction and moves to the left side of the illustrated arrow. When the direction of the current flowing through the coil 12 is changed, the direction of the magnetic flux flowing through the stator core 14 is reversed. As a result, the magnetic flux of the right magnet 46b becomes stronger than the magnetic flux of the left magnet 46a. Receives the thrust in the right direction and moves to the right of the illustrated arrow.
[0021]
Therefore, also in this embodiment, the movable magnet body 42 can be continuously reciprocated by supplying an alternating current to the coil 12 of the stator core 14.
Further, in another embodiment of the MM type linear vibration motor 10 shown in FIGS. 5A and 5B, the outer laminated core 22 constituting the stator core 14 is made cylindrical as compared with the embodiment of FIG. The other components are the same except that the inner laminated core 24 in which one coil 12 is wound is formed in a cylindrical shape, and the other configurations are the same. Is omitted. Then, a cylindrical inner laminated core 24 is inserted and disposed concentrically in the inner space of the cylindrical outer laminated core 22, and is displaced in the axial direction into a cylindrical magnetic gap 16 formed between the two cores. The movable magnet body 42 is arranged. The movable magnet body 42 holds a pair of permanent magnets 46 and 46 formed in a circular arc shape on the open end side of a bottomed cylindrical magnet holding frame 44 having a shaft 36. Each permanent magnet 46 is divided into magnets 46a and 46b in the axial direction and magnetized in the opposite direction to the radial direction.
[0022]
The operation principle of this embodiment is the same as that of the embodiment of FIG.
[Brief description of the drawings]
FIGS. 1A and 1B are schematic views corresponding to AA and BB of a movable iron core (MI) type linear vibration motor according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view of the MI type linear vibration motor shown in FIG.
FIGS. 3A and 3B are schematic views of an MI type linear vibration motor showing another embodiment corresponding to FIGS. 1A and 1B. FIGS.
4A and 4B are illustrative views corresponding to AA and BB of a movable magnet (MM) type linear vibration motor showing another embodiment of the present invention. FIG.
FIGS. 5A and 5B are schematic views of an MM type linear vibration motor showing another embodiment corresponding to FIGS. 4A and 4B. FIGS.
6A and 6B are illustrative views of a conventional MI-type linear vibration motor corresponding to FIGS. 1A and 1B. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Linear vibration motor 12 ... Coil 14 ... Stator iron core 16 ... Magnetic space 18 ... Movable iron core body 20 ... U-shaped groove part 22 ... Outer laminated core 24 ... Inner laminated core 26 ... Salient pole part 30, 32, 46 ... Permanent magnet 34 ... movable holder 36 ... shaft 38 ... holding piece 40 ... movable iron core 42 ... movable magnet body 44 ... magnet holding frame

Claims

In a linear vibration motor in which a movable iron core is disposed so as to be axially displaceable in a magnetic gap of a stator iron core having a coil,
The fixed iron core is a cylindrical outer core having permanent magnets mounted on the inner surface at predetermined intervals, and a columnar shape in which the coils are wound around salient poles formed outward and the permanent magnets are mounted on the outer surfaces between the coils. With an inner core,
The linear vibration motor, wherein the inner core is inserted and arranged in the outer core so that the permanent magnet of the inner core faces the permanent magnet of the outer core to form the magnetic gap.

The linear vibration motor according to claim 1, wherein the permanent magnet attached to the outer core and the permanent magnet attached to the inner core are both divided and magnetized in the opposite radial direction.

3. The linear vibration motor according to claim 1, wherein the inner surface of the outer core includes an axial recess that accommodates at least an end of the coil.

The linear vibration motor according to claim 3, wherein the recess includes a groove.

The outer core including the permanent magnet has a cylindrical shape, the inner core including the permanent magnet and the coil has a cylindrical shape, and is stacked in a cylindrical shape in the magnetic gap formed by the outer core and the inner core. The linear vibration motor according to claim 1, wherein the movable iron core is disposed.

In a linear vibration motor in which a movable magnet body is arranged to be axially displaceable in a magnetic gap of a stator core having a coil,
The fixed iron core includes a cylindrical outer core, and a columnar inner core in which the coil is wound around a salient pole portion formed outwardly,
Inserting and arranging the inner core into the outer core so as to form the magnetic gap;
The linear vibration motor according to claim 1, wherein an inner surface of the outer core includes an axial recess that accommodates at least an end of the coil.

The linear vibration motor according to claim 6, wherein the recess includes a groove.

The linear vibration motor according to claim 6, wherein the movable magnet body includes a divided permanent magnet, and the permanent magnet is magnetized in the opposite direction in the radial direction.