JPS5899251A - Permanent magnet for rotary electric machinery - Google Patents
Permanent magnet for rotary electric machineryInfo
- Publication number
- JPS5899251A JPS5899251A JP19620681A JP19620681A JPS5899251A JP S5899251 A JPS5899251 A JP S5899251A JP 19620681 A JP19620681 A JP 19620681A JP 19620681 A JP19620681 A JP 19620681A JP S5899251 A JPS5899251 A JP S5899251A
- Authority
- JP
- Japan
- Prior art keywords
- magnet
- armature
- permanent magnet
- ferrite
- arc segment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- H01F41/0286—Trimming
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K23/00—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors
- H02K23/02—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors characterised by arrangement for exciting
- H02K23/04—DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors characterised by arrangement for exciting having permanent magnet excitation
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Dc Machiner (AREA)
- Permanent Field Magnets Of Synchronous Machinery (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は回転電気機械用永久磁石に係り、特に電機子と
の間の空隙を介してアークセグメント状フェライト磁石
を有する永久磁石式小型直流モータ、発電機用の永久磁
石に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a permanent magnet for a rotating electric machine, and more particularly to a permanent magnet for a small permanent magnet direct current motor or a generator having an arc segment-shaped ferrite magnet through an air gap between the armature and the armature. It is related to.
従来から永久磁石を用いた回転電気機械、特にアークセ
グメント状7エライト磁石を用いた小型モータ、発電機
等が広く使用されており、近年は大型モータへもフェラ
イト磁石の応用分野が広がっている。特にエンジン起動
用のスターターモータ、ニアコンディショナーのフンブ
レフサ−駆動用モータ等、起動時の負荷が非常に大きい
モータが多くなって来た。このため、電機子反作用によ
る減磁界が大きいので、フェライト磁石の中でも特に減
磁耐力の大きい磁石が使用されている。しかしフェライ
ト磁石は特にスターターモータ用のものが異常時の過電
流、低温時における起動電流によ#)1大きく減磁する
ことがあり信頼性の面で十分であるとはいえない。この
対策としては、特開昭55−56456号で開示されて
いるように電機子反作用による減磁界が加わる部分に固
有保磁力(以下rHoと記す)の高い材料を使用し、残
りの部分に残留磁束密度(以下Brと記す)の高い材料
とすることが提唱されている。しかし工Haの高い材料
の占める割合が小さければ上記両材料の接合部付近で減
磁し、逆にその割合が大きければ全体的に有効磁束量が
低下して、モータ特性が低下するという欠陥があった。BACKGROUND ART Rotary electric machines using permanent magnets, particularly small motors, generators, etc. using arc segment-shaped 7-elite magnets have been widely used, and in recent years, the field of application of ferrite magnets has expanded to large motors as well. In particular, there have been an increase in the number of motors that have a very large load during startup, such as starter motors for engine startup and motors for driving the hub brakes of near conditioners. For this reason, since the demagnetizing field due to armature reaction is large, magnets with especially high demagnetizing strength among ferrite magnets are used. However, ferrite magnets, especially those for starter motors, can be significantly demagnetized due to overcurrent during abnormal conditions or starting current at low temperatures, and cannot be said to be sufficiently reliable in terms of reliability. As a countermeasure to this problem, as disclosed in JP-A No. 55-56456, a material with high intrinsic coercive force (hereinafter referred to as rHo) is used in the part where the demagnetizing field due to armature reaction is applied, and the remaining part is It has been proposed to use a material with high magnetic flux density (hereinafter referred to as Br). However, if the proportion of the material with high engineering Ha is small, demagnetization will occur near the joint between the above two materials, and conversely, if the proportion is large, the effective magnetic flux will decrease overall, resulting in a defect that the motor characteristics will deteriorate. there were.
第1図は磁気特性の異なる2つの材料を組み合わせた従
来の例で、ステータヨークl[アークセグメント状のフ
ェライト磁石21を角度θmの範囲に有して−る。そし
てこのアークセグメント状の7工ライト磁石2は、電機
子4の回転方向(矢印方向)側す力わち走出側の端部か
ら0mのV3程度の角度θ、の部分に高IHO材3が設
けられて、電機予盛の反作用による減磁−を避け、他の
部分は高Br材怠になっている。しかしながら、高Br
材2のxHa が小さいと2つの材料の接合部で第2
図の空隙磁束密度分布図に示すように1起動時の電機予
盛の反作用により大きく減磁する場合がある。そのため
、高Br材2についても上記減磁を避けるためには、高
工HO磁石3に近いxKaを確保しなければならず、そ
の場合BrとxHcとのバランスからその分だけBrが
低下することになるので有効磁束量が小さくなり、モー
タとして最適とはいえない問題点がある。(第2図中、
番は飽和着磁後の状態を示す曲線、bは過大電流の電機
子反作用における減磁界で減磁した状態を示す曲線であ
る。)
本発明は一上記従来の問題点を解決すると共に〜モータ
特性を低下させることはなく、低温度雰囲気等の悪条件
下でも電機子の反作用による減磁がほとんど起きない、
減磁耐力に優れ1かつ信頼性の高い複合型フェライト磁
石よりなる回転電気機械用永久磁石を提供することを目
的とするものである。FIG. 1 shows a conventional example in which two materials with different magnetic properties are combined, and a stator yoke l has arc segment-shaped ferrite magnets 21 in the range of angle θm. This arc segment-shaped 7-piece light magnet 2 has a high IHO material 3 at an angle θ of about V3 at 0 m from the end of the armature 4 in the rotation direction (arrow direction), that is, the running side. The other parts are made of high Br material to avoid demagnetization caused by the reaction of the electric machine preload. However, high Br
If xHa of material 2 is small, the second
As shown in the air gap magnetic flux density distribution diagram in the figure, significant demagnetization may occur due to the reaction of the electric machine pre-loading during one startup. Therefore, in order to avoid the above demagnetization for the high Br material 2, it is necessary to ensure xKa close to that of the high-quality HO magnet 3, and in that case, the Br will decrease by that amount from the balance between Br and xHc. Therefore, the amount of effective magnetic flux becomes small, which poses the problem that it is not optimal as a motor. (In Figure 2,
Curve number indicates the state after saturation magnetization, and curve b indicates the state demagnetized by the demagnetizing field in the armature reaction of excessive current. ) The present invention solves the above-mentioned problems of the conventional motor, and also does not cause deterioration of motor characteristics, and almost no demagnetization due to armature reaction occurs even under adverse conditions such as low temperature atmosphere.
The object of the present invention is to provide a permanent magnet for a rotating electrical machine made of a composite ferrite magnet that has excellent demagnetization resistance and high reliability.
本発明は、アークセグメント状磁石のほぼ中央部より電
機子の回転方向と逆方向側の端部までの間を高Br材に
して有効磁束量を確保すると共に1減磁界が加わる残余
の部分は、減磁界に相当する減磁耐力0IHOを電機子
の回転方向側に向ってほぼ連続的に増加させ、かつBr
を同方向にはは連続的に減少させて電機子の反作用によ
る減磁を防止し、有効磁束量を増やしてモータの性能向
上を行うことを特徴とするものである。The present invention uses a high Br material from the approximate center of the arc segment-shaped magnet to the end opposite to the rotational direction of the armature to ensure an effective amount of magnetic flux, and the remaining portion to which one demagnetizing field is applied is , the demagnetization resistance 0IHO corresponding to the demagnetizing field increases almost continuously in the direction of rotation of the armature, and Br
The magnetic flux is continuously decreased in the same direction to prevent demagnetization due to armature reaction and increase the amount of effective magnetic flux to improve the performance of the motor.
以下本発明の一実施例を図面によって説明する。An embodiment of the present invention will be described below with reference to the drawings.
第3図は永久磁石式直流モータの断面図で、ステータ冒
−り1の内側には角度θmの範囲にアークセグメント状
のフェライト磁石21を固定している。この磁石21は
、電機子40回転方向(矢印方向)と逆方向側(走入側
)の上記磁石21のほぼ半分を高Brを有する7工ライ
ト磁石2とし、回転方向と同一方向側(走出側)の峰に
半分を1ト磁石30〜35としたものである。すなわち
フェライト磁石!!1は、その中央部側に高Brでかつ
低IHa材としたフェライト磁石35を、また端部側に
高xHoでかつ低Br材としたフェライト磁石30を有
するものである。FIG. 3 is a sectional view of a permanent magnet DC motor, in which arc segment-shaped ferrite magnets 21 are fixed inside the stator rim 1 within an angle .theta.m. In this magnet 21, approximately half of the above-mentioned magnet 21 on the opposite side (running side) to the direction of rotation of the armature 40 (arrow direction) is a 7-piece light magnet 2 having a high Br, and the side in the same direction as the rotation direction (running side) One half of the peak on the side) is made up of 30 to 35 magnets. In other words, a ferrite magnet! ! No. 1 has a ferrite magnet 35 made of a high Br and low IHa material on the center side, and a ferrite magnet 30 made of a high xHo and low Br material on the end side.
第4図は電機子と永久磁石との空隙部の磁束密度分布図
であり11曲線は飽和着磁後の状態であり、1曲線は過
大電流の電機子反作用における減磁界で減iした状態を
示す。第4図のように本発明の永久磁石は、外部の減磁
界に対して非常に安定で減磁が少なく、信頼性の高い直
流モータ用として使用できるものである。フェライト磁
石は減磁耐力を上げるために、zHoを高くすることが
有効であるが、同時にBrが低下するため空隙磁束密度
が下り、有効磁束量も減少してモータのトルク性能も低
下する。しかし本発明の場合は端部の磁石30に高rH
c材を使っても、磁石全体に占める体積比率が小さいた
め、モータ性能の低下を最小限に抑えて信頼性の高いモ
ータとすることができるものである。Figure 4 is a magnetic flux density distribution diagram in the gap between the armature and the permanent magnet. Curve 11 shows the state after saturation magnetization, and curve 1 shows the state where i is reduced by the demagnetizing field due to the armature reaction of excessive current. show. As shown in FIG. 4, the permanent magnet of the present invention is very stable against external demagnetizing fields, exhibits little demagnetization, and can be used for highly reliable DC motors. In order to increase the demagnetization resistance of ferrite magnets, it is effective to increase zHo, but at the same time, the Br decreases, so the air gap magnetic flux density decreases, the amount of effective magnetic flux also decreases, and the torque performance of the motor also decreases. However, in the case of the present invention, the magnet 30 at the end has a high rH.
Even if C material is used, since the volume ratio of the magnet to the entire magnet is small, deterioration in motor performance can be minimized and a highly reliable motor can be obtained.
本発明の永久磁石の磁気特性を連続的に変化させるには
、例えばアルミニウム酸化物およびその他の金属酸化物
の含有量を連続的に変化させた磁石を作り、これらの磁
石を組み合わせることによって特性値が異なる磁石とす
ることができるものである。In order to continuously change the magnetic properties of the permanent magnet of the present invention, for example, by making magnets in which the contents of aluminum oxide and other metal oxides are continuously changed, and combining these magnets, the characteristic value can be changed. can be made of different magnets.
第6図は本発明の他の実施例を示すものであり、減磁界
の大きい表面に対して外周は磁気特性を少しでも有効に
活用するために磁束の流れやすいように各磁石2.36
〜41の各境界面(等磁気特性面)22を斜めとしたも
のである。Fig. 6 shows another embodiment of the present invention, in which each magnet has a diameter of 2.36 cm on the outer periphery so that the magnetic flux can easily flow on the surface where the demagnetizing field is large in order to utilize the magnetic properties as effectively as possible.
.about.41 (equal magnetic characteristic surfaces) 22 are oblique.
第6図は本発明のさらに他の実施例を示すものであつ、
外周ヨーク11が固定された電機子で、空隙を介して内
周の永久磁石がロータとして回転するタイプの直流ブラ
シレスモータの例である。FIG. 6 shows still another embodiment of the present invention,
This is an example of a DC brushless motor in which an armature has a fixed outer yoke 11, and a permanent magnet on the inner circumference rotates as a rotor through an air gap.
アークセグメント状のフェライト磁石121は、内周ヨ
ーク14の外周に固着され、前記第3図のものとP!ホ
同様に、走入側に高Brのフェライト磁石12を、また
走出側は上記磁石121の中央部より端部にかけて7分
割したフェライト磁石43〜49を有している。しかし
て中央部の磁石49から端部の磁石43に向ってBrを
高4低に、I Hcを低→高に変化させたものである。The arc segment-shaped ferrite magnet 121 is fixed to the outer periphery of the inner yoke 14, and is similar to the one shown in FIG. Similarly, a high Br ferrite magnet 12 is provided on the entry side, and ferrite magnets 43 to 49 are provided on the exit side, which are divided into seven parts from the center to the ends of the magnet 121. Thus, Br is changed from high to 4 low and IHc is changed from low to high from the magnet 49 at the center to the magnet 43 at the end.
本実施例の場合、特に起動時に起きる電機子反作用によ
る減磁界に対して耐力が高く、非常に信頼度の高いモー
タとすることができる。In the case of this embodiment, the motor has a high resistance to a demagnetizing field caused by an armature reaction that occurs particularly during startup, and can be made to be a highly reliable motor.
アークセグメント状フェライト磁石の磁気特性を第7図
に減磁特性曲線で示す。図中2は高Br材の特性、30
−35は高IHO材の特性である。The magnetic characteristics of the arc segment-shaped ferrite magnet are shown in FIG. 7 as a demagnetization characteristic curve. 2 in the figure is the characteristic of high Br material, 30
-35 is a characteristic of high IHO material.
以上説明した如く本発明は、直流モータ等の回転電気機
械におけるアークセグメント状フェライト磁石の片側は
は半分において、srs 工Hoの磁気特性を連続的
に変えることにより、次なる効果が得られた。As explained above, the present invention achieves the following effects by continuously changing the magnetic properties of the SRS in one half of an arc segment-shaped ferrite magnet in a rotating electric machine such as a DC motor.
l) 従来の2種の複合磁石使用の直流モータに対し、
モータのトルク特性を低下させることなく減磁耐力を1
.3倍以上に向上することができる。l) Compared to the conventional DC motor using two types of composite magnets,
Reduced demagnetization resistance by 1 without reducing motor torque characteristics.
.. It can be improved by more than 3 times.
2) 単一材料を使う直流モータに対し1減磁界に対す
る安定性、モータのトルク特性を共に向上させることが
できる。2) Compared to a DC motor that uses a single material, it is possible to improve both the stability against a demagnetizing field and the torque characteristics of the motor.
3) モータのシルク特性は、従来の複合磁石型に比し
同じ減磁耐力であれば、本発明ではW幡以上の性能アッ
プが期待できる03) Regarding the silk characteristics of the motor, compared to the conventional composite magnet type, if the demagnetization resistance is the same, the present invention can be expected to improve performance by more than W.
第1図は従来例によるモータの断面図・第2図は第1図
の従来例の空隙部の磁束密度分布図、第3図は本発明の
一実施例による永久磁石式直流モータの断面図、第4図
は第3図の実施例における空隙部の磁束密度分布図、第
5・図および第6図は本発明の他の実施例によるモータ
の断面図、第7図は本発明のフェライト磁石の磁気特性
を示す特性曲線図である。
、21.121:アークセグメント状フェライト磁石(
全体)、2.12ニア工ライト磁石(高Br材)、30
〜35.36〜41.43〜49;磁気特性の異なるフ
ェライト磁石、4.14:電機子
代理人 弁理士 本 間 崇
隼7図
第3 @・
第 、2 図
繍4図Figure 1 is a sectional view of a conventional motor. Figure 2 is a magnetic flux density distribution diagram in the air gap of the conventional example in Figure 1. Figure 3 is a sectional view of a permanent magnet DC motor according to an embodiment of the present invention. , FIG. 4 is a magnetic flux density distribution diagram of the air gap in the embodiment shown in FIG. 3, FIGS. 5, 6, and 6 are sectional views of motors according to other embodiments of the present invention, and FIG. 7 is a diagram of the ferrite of the present invention. FIG. 3 is a characteristic curve diagram showing the magnetic characteristics of a magnet. , 21.121: Arc segment-shaped ferrite magnet (
overall), 2.12 near-machined light magnet (high Br material), 30
~35.36~41.43~49; Ferrite magnets with different magnetic properties, 4.14: Armature agent Patent attorney Takashi Honma 7 Figure 3 @, 2, 2 Figure 4
Claims (1)
して設けた少くとも2個のアークセグメント状のフェラ
イト磁石よりなる回転電気機械用永久磁石において、該
永久磁石の嫌ホ中央部より一上記電機子の回転方向と逆
方向側の端部までの間を高い残留磁束密度を有する7工
ライト磁石とし、残余の部分を上記電機子の回転方向側
の端部に向って、はぼ連続的に残留磁束密度が減少し、
かつ固有保磁力が増加する磁気特性を有するフェライト
磁石としたことを特徴とする回転電気機械用永久磁石。 2、磁気特性がほぼ連続的に変わるアークセグメンY状
7エライシ磁石の固有保磁力が次の式で表わされること
を特徴とする特許請求の範囲第1項記載の回転電気機械
用永久磁石。 但し% IHO、−−−7工ライト磁石の固有保磁力 Lg 0.、、電機子とフェライト磁−石間の空隙 Lm、、、、アークセグメント状フ ェライト磁石の厚さ θ 000.アークセグメント状磁石の中央部から
端部までの角度 ム丁 000.電機子の全一体数[Claims] 1. A permanent magnet for a rotating electric machine comprising at least two arc segment-shaped ferrite magnets arranged diametrically opposite to each other with a gap between them and the armature. A 7-piece light magnet with high residual magnetic flux density is used between the center of the permanent magnet and the end opposite to the rotation direction of the armature, and the remaining part is placed on the side opposite to the rotation direction of the armature. The residual magnetic flux density decreases almost continuously toward the end,
A permanent magnet for a rotating electrical machine, characterized in that it is a ferrite magnet having magnetic properties that increase its intrinsic coercive force. 2. A permanent magnet for a rotating electrical machine according to claim 1, wherein the intrinsic coercive force of the arc segment Y-shaped 7-element magnet whose magnetic properties change almost continuously is expressed by the following formula. However, % IHO, ---7 Intrinsic coercive force Lg of light magnet 0. ,, air gap Lm between armature and ferrite magnet, , thickness of arc segment-shaped ferrite magnet θ 000. The angle from the center to the end of the arc segment magnet 000. Total number of armatures
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP19620681A JPS5899251A (en) | 1981-12-05 | 1981-12-05 | Permanent magnet for rotary electric machinery |
PCT/JP1982/000265 WO1983000264A1 (en) | 1981-07-14 | 1982-07-14 | Field composite permanent magnet and method of producing the same |
US06/743,274 US4687608A (en) | 1981-07-14 | 1982-07-14 | Composite permanent magnet for magnetic excitation and method of producing the same |
GB08306781A GB2112578B (en) | 1981-07-14 | 1982-07-14 | Field composite permanent magnet and method of producing the same |
DE823248846T DE3248846T1 (en) | 1981-07-14 | 1982-07-14 | COMPOSITE PERSONAL MAGNET FOR MAGNETIC EXCITATION AND METHOD FOR ITS MANUFACTURING |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP19620681A JPS5899251A (en) | 1981-12-05 | 1981-12-05 | Permanent magnet for rotary electric machinery |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5899251A true JPS5899251A (en) | 1983-06-13 |
Family
ID=16353956
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP19620681A Pending JPS5899251A (en) | 1981-07-14 | 1981-12-05 | Permanent magnet for rotary electric machinery |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5899251A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS592555A (en) * | 1982-06-28 | 1984-01-09 | Hitachi Ltd | Permanent magnet field dc machine |
JPS59136056A (en) * | 1983-01-26 | 1984-08-04 | Hitachi Ltd | Field pole and producing method therefor |
JP2008258585A (en) * | 2007-03-13 | 2008-10-23 | Daido Steel Co Ltd | Synthetic molded body for permanent magnet and manufacturing method for permanent magnet raw material |
JP2009284746A (en) * | 2007-11-05 | 2009-12-03 | Toshiba Corp | Permanent magnet motor and washing machine |
WO2012105656A1 (en) * | 2011-02-04 | 2012-08-09 | 三菱電機株式会社 | Embedded permanent magnet type rotating electrical machine for vehicle |
-
1981
- 1981-12-05 JP JP19620681A patent/JPS5899251A/en active Pending
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS592555A (en) * | 1982-06-28 | 1984-01-09 | Hitachi Ltd | Permanent magnet field dc machine |
JPH0116103B2 (en) * | 1982-06-28 | 1989-03-22 | Hitachi Ltd | |
JPS59136056A (en) * | 1983-01-26 | 1984-08-04 | Hitachi Ltd | Field pole and producing method therefor |
JPH0224110B2 (en) * | 1983-01-26 | 1990-05-28 | Hitachi Ltd | |
JP2008258585A (en) * | 2007-03-13 | 2008-10-23 | Daido Steel Co Ltd | Synthetic molded body for permanent magnet and manufacturing method for permanent magnet raw material |
JP2009284746A (en) * | 2007-11-05 | 2009-12-03 | Toshiba Corp | Permanent magnet motor and washing machine |
WO2012105656A1 (en) * | 2011-02-04 | 2012-08-09 | 三菱電機株式会社 | Embedded permanent magnet type rotating electrical machine for vehicle |
JP5709907B2 (en) * | 2011-02-04 | 2015-04-30 | 三菱電機株式会社 | Permanent magnet embedded rotary electric machine for vehicles |
US9172279B2 (en) | 2011-02-04 | 2015-10-27 | Mitsubishi Electric Corporation | Automotive embedded permanent magnet rotary electric machine |
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