JPS64808B2 - - Google Patents
Info
- Publication number
- JPS64808B2 JPS64808B2 JP57184369A JP18436982A JPS64808B2 JP S64808 B2 JPS64808 B2 JP S64808B2 JP 57184369 A JP57184369 A JP 57184369A JP 18436982 A JP18436982 A JP 18436982A JP S64808 B2 JPS64808 B2 JP S64808B2
- Authority
- JP
- Japan
- Prior art keywords
- wall mold
- magnetic field
- slurry
- ferrite
- cavity
- 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.)
- Expired
Links
- 229910000859 α-Fe Inorganic materials 0.000 claims description 20
- 239000002002 slurry Substances 0.000 claims description 16
- 239000000843 powder Substances 0.000 claims description 12
- 238000000465 moulding Methods 0.000 claims description 10
- 238000001914 filtration Methods 0.000 claims description 5
- 239000007788 liquid Substances 0.000 claims description 4
- 238000000034 method Methods 0.000 description 10
- 230000004907 flux Effects 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000005405 multipole Effects 0.000 description 3
- 229910052761 rare earth metal Inorganic materials 0.000 description 3
- 150000002910 rare earth metals Chemical class 0.000 description 3
- 229910052712 strontium Inorganic materials 0.000 description 3
- 238000000748 compression moulding Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000020169 heat generation Effects 0.000 description 2
- 230000005415 magnetization Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Hard Magnetic Materials (AREA)
- Manufacturing Cores, Coils, And Magnets (AREA)
Description
【発明の詳細な説明】
本発明は異方性フエライト磁石の製造に関する
もので、特に、半径方向に異方性を与えるための
磁性スラリーの磁場中成型装置に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the production of anisotropic ferrite magnets, and in particular to an apparatus for molding magnetic slurry in a magnetic field to impart anisotropy in the radial direction.
フエライト磁石のプレス成型工程において、フ
エライト磁石粒子が分子式MO・6Fe2O3（Ｍは
Ba，Sr，Pbの一種）をもつマグネトプランバイ
ト相の板状の六方晶系の構造をとり、六回対称軸
の方向に磁気容易軸（Ｃ軸）をとることからこの
性質を利用し、磁場印加などでＣ軸方向をそろえ
るものとそろえないものとに大別され、前者を異
方性磁石、後者を等方性磁石と呼び、一般に市販
されている。また、異方性磁石の成型において
は、フエライト磁石粉末を金型に充填して、圧縮
成型する方法と、フエライト磁石粉末を水等の液
体に懸濁した泥漿（スラリー）として圧縮成型す
る方法が知られており、前者は乾式法、後者は湿
式法と呼ばれ、湿式法は、フエライト磁石粒子の
配向性に秀れ、磁石特性は乾式法に比し格段に秀
れている。すなわち、磁石特性が一番高いものは
湿式の異方性磁石である。 In the press molding process of ferrite magnets, ferrite magnet particles have a molecular formula of MO・6Fe 2 O 3 (M is
It takes advantage of this property because it has a plate-like hexagonal structure of magnetoplumbite phase with a type of magnetoplumbite (Ba, Sr, Pb), and the magnetic easy axis (C axis) is in the direction of the six-fold symmetry axis. There are two types of magnets: those whose C-axis directions are aligned by applying a magnetic field and those whose C-axis directions are not aligned.The former are called anisotropic magnets, and the latter are called isotropic magnets, and are generally commercially available. In addition, when molding anisotropic magnets, there are two methods: filling a mold with ferrite magnet powder and compression molding, and compression molding the ferrite magnet powder as a slurry suspended in a liquid such as water. The former method is known as the dry method, and the latter is called the wet method. The wet method has excellent orientation of ferrite magnet particles and has much better magnetic properties than the dry method. That is, the wet anisotropic magnet has the highest magnetic properties.
スピーカー用フエライト磁石の製造において
は、このような湿式磁場プレスが採用されている
が、そこでは加圧方向と同方向に磁場を印加して
得られる。 In the manufacture of ferrite magnets for speakers, such a wet magnetic field press is employed, where a magnetic field is applied in the same direction as the pressing direction.
ところが、加圧方向と直角方向特に放射方向に
磁場を印加することは困難であるので、モータあ
るいは発電機あるいは電子複写機などに用いられ
る円筒状の永久磁石では、等方性の永久磁石を用
いているが、等方性の場合表面磁束密度は700〜
1000ガウス程度であつた。 However, it is difficult to apply a magnetic field in a direction perpendicular to the pressure direction, especially in the radial direction, so isotropic permanent magnets are used for cylindrical permanent magnets used in motors, generators, electronic copying machines, etc. However, in the case of isotropy, the surface magnetic flux density is 700 ~
It was about 1000 Gauss.
本発明はこのような欠点を解決するために、第
１図に示すように、フエライト粉末を充填する円
筒状キヤビテイ１０に半径方向の磁力を作用させ
るために、円筒状キヤビテイの更に内側に多極の
磁極を放射状に配して、フエライト粉末を半径方
向に磁場配向させ、円筒状磁石の表面磁束密度を
向上させることを意図するものである。 In order to solve these drawbacks, the present invention, as shown in FIG. 1, has a multi-pole structure further inside the cylindrical cavity in order to apply a radial magnetic force to the cylindrical cavity 10 filled with ferrite powder. It is intended that the magnetic poles of the cylindrical magnet be arranged radially to orient the ferrite powder in the radial direction of the magnetic field, thereby improving the surface magnetic flux density of the cylindrical magnet.
ところで、従来の磁場中成型では、印加磁場の
発生には電磁石を用いている。従つて、従来どお
り電磁石を用いて、第１図のように半径方向の磁
力（点線で示す）を作用させることはほとんど不
可能である。 By the way, in conventional molding in a magnetic field, an electromagnet is used to generate the applied magnetic field. Therefore, it is almost impossible to apply a radial magnetic force (indicated by a dotted line) as shown in FIG. 1 using conventional electromagnets.
例えばストロンチウムフエライトの製造におい
ては、磁場中成型時に、湿式法であつても
3000Gauss以上の磁場が必要であるが、円筒状キ
ヤビテイ１０の内径が20mm以下とすれば、電磁石
コイルの線径、コイルの発熱あるいはコイルのス
ペースを堪案すると、実現できるのはわずか２極
でしかなく、これでは放射方向に異方性を付与す
ることは不可能である。 For example, in the production of strontium ferrite, even if it is a wet method when molding in a magnetic field.
A magnetic field of 3000 Gauss or more is required, but if the inner diameter of the cylindrical cavity 10 is 20 mm or less, only two poles can be achieved, considering the wire diameter of the electromagnetic coil, the heat generation of the coil, and the space of the coil. This makes it impossible to impart anisotropy in the radial direction.
以上の点に鑑み、本発明は、放射状方向に異方
性を付与でき、しかも小型化可能な、フエライト
スラリーの磁場中成型装置を提供することを目的
とする。 In view of the above points, an object of the present invention is to provide an apparatus for molding ferrite slurry in a magnetic field, which can impart anisotropy in the radial direction and can be downsized.
本発明は、円筒状の半径方向に磁場を加えなが
ら加圧成型するフエライトスラリーの磁場中成型
装置であつて、孔部を有する外壁金型と、該孔部
に配置された上記外壁金型との間に円筒状のキヤ
ビテイを形成する内壁金型と、該円筒状のキヤビ
テイに半径方向の磁力を作用させるように該内壁
金型内に組み込まれた複数の永久磁石と、上記円
筒状キヤビテイにフエライト粉末のスラリーを供
給する機構と、該円筒状キヤビテイに出入りする
下パンチと、該キヤビテイの下パンチと反対側で
両金型に設置されたスラリー中の液体の過のた
めの過装置とを有することを特徴とするフエラ
イトスラリーの磁場中成型装置である。 The present invention is an apparatus for molding ferrite slurry under pressure while applying a magnetic field in the radial direction of a cylinder, and includes an outer wall mold having a hole, and the outer wall mold disposed in the hole. an inner wall mold forming a cylindrical cavity therebetween; a plurality of permanent magnets incorporated into the inner wall mold so as to apply a radial magnetic force to the cylindrical cavity; A mechanism for supplying slurry of ferrite powder, a lower punch that enters and exits the cylindrical cavity, and a filtration device for filtrating the liquid in the slurry, which is installed in both molds on the opposite side of the lower punch of the cavity. A ferrite slurry forming apparatus in a magnetic field is characterized by having the following features.
上記複数の永久磁石は、内壁金型の軸方向と直
角方向に着磁された４つ以上の永久磁石で、Ｎ，
Ｓ極が交互に内壁金型の外周面に沿つて並ぶよう
に配置されたものである。従つて、各永久磁石の
径方向内側の磁極は互いに接近し、磁気的に短絡
されたほとんど同様の状態となる。 The plurality of permanent magnets are four or more permanent magnets magnetized in a direction perpendicular to the axial direction of the inner wall mold, N,
The S poles are arranged alternately along the outer peripheral surface of the inner wall mold. Therefore, the radially inner magnetic poles of each permanent magnet come close to each other and are in almost the same magnetically short-circuited state.
なお、永久磁石としては、高性能である希土類
磁石を用いると良い。希土類磁石の場合、最大エ
ネルギー（BH）maxが28MGOe以上、更に
32MGOe以上のものも得られている。 Note that it is preferable to use a high-performance rare earth magnet as the permanent magnet. For rare earth magnets, the maximum energy (BH) max is 28MGOe or more, and
More than 32MGOe have also been obtained.
本発明によれば、印加磁場発生用として占有容
積の大となる電磁石を用いることなく、永久磁石
を用い、これを円筒状キヤビテイの内面を規定す
る内壁金型内に多極に配したので、小型で、しか
も放射状方向の磁場配向を容易に実現できる。 According to the present invention, permanent magnets are used for generating an applied magnetic field without using electromagnets that occupy a large volume, and these are arranged in multi-pole form within the inner wall mold that defines the inner surface of the cylindrical cavity. It is compact and can easily achieve magnetic field orientation in the radial direction.
以下、本発明の実施例を第２図を参照して詳細
に説明する。第２図を参照して、孔部を有する外
壁金型１の孔部中に内壁金型２が配置され、両金
型１，２の間にリング状即ち円筒状のキヤビテイ
１０が形成されている。内壁金型２内には、複数
の希土類永久磁石体３がその磁化方向を半径方向
にして等角度間隔に配置固定されている。ここで
隣接する磁石体３の磁化の向きは逆となつてい
る。なお、外壁金型１と内壁金型２のキヤビテイ
１０に対向する面は、プレス時の圧力に耐えるよ
うに超硬合金で保護される。 Hereinafter, embodiments of the present invention will be described in detail with reference to FIG. Referring to FIG. 2, an inner wall mold 2 is placed in a hole of an outer wall mold 1 having a hole, and a ring-shaped, ie, cylindrical, cavity 10 is formed between both molds 1 and 2. There is. Inside the inner wall mold 2, a plurality of rare earth permanent magnet bodies 3 are arranged and fixed at equal angular intervals with their magnetization direction being radial. Here, the magnetization directions of adjacent magnet bodies 3 are opposite. Note that the surfaces of the outer wall mold 1 and the inner wall mold 2 facing the cavity 10 are protected by cemented carbide so as to withstand pressure during pressing.
キヤビテイ１０の下方から、下パンチ４が上下
動可能に挿入されており、外壁金型１には、キヤ
ビテイ１０へスラリーを注入する供給孔５が設け
られている。両金型１，２の上部には、スラリー
中の液体を過排水するための過孔６を備えた
過装置７が設置されている。 A lower punch 4 is inserted from below the cavity 10 so as to be movable up and down, and the outer wall mold 1 is provided with a supply hole 5 for injecting slurry into the cavity 10. A filtration device 7 equipped with a filtration hole 6 for draining liquid in the slurry is installed above both molds 1 and 2.
以上の装置において、フエライト粉末のスラリ
ーを矢印のように、供給孔５からキヤビテイ１０
中へ圧入すると、粉末は永久磁石体３の磁力によ
り半径方向に配向される。ここで、永久磁石３の
径方向内側の磁極は互いにきわめて接近している
から短絡されているのとほとんど同じ状態とな
り、それ故、外側のキヤビテイ内に充分高い配向
磁場を形成することができる。この状態で、下パ
ンチを上昇させることにより、スラリーは圧縮さ
れるので、その水分が過孔６から押し出され、
フエライト粉末は脱水され、粗の状態から密の状
態に成型される。 In the above apparatus, the slurry of ferrite powder is supplied from the supply hole 5 to the cavity 10 as shown by the arrow.
When pressed into the powder, the powder is oriented in the radial direction by the magnetic force of the permanent magnet body 3. Here, since the radially inner magnetic poles of the permanent magnet 3 are very close to each other, the state is almost the same as being short-circuited, and therefore a sufficiently high alignment magnetic field can be created in the outer cavity. In this state, by raising the lower punch, the slurry is compressed, and its moisture is pushed out through the holes 6.
The ferrite powder is dehydrated and shaped from a coarse state to a dense state.
本装置を用い磁場印加のための永久磁石体３を
図示のとおり８極として、ストロンチウムフエラ
イト粉末のスラリーを外径36mm、内径16mm、長さ
60mmなる円筒状に成型し、この成型体を1220℃で
焼結後、異方化と同方向に８極の着磁をしたとこ
ろ、表面磁束密度として1400〜1500ガウスを得
た。 Using this device, the permanent magnet 3 for applying a magnetic field has 8 poles as shown in the figure, and the slurry of strontium ferrite powder has an outer diameter of 36 mm, an inner diameter of 16 mm, and a length of
It was molded into a 60 mm cylindrical shape, and after sintering this molded body at 1220°C, it was magnetized with 8 poles in the same direction as the anisotropy, and a surface magnetic flux density of 1400 to 1500 Gauss was obtained.
以上、本発明を実施例について説明したが、本
発明によれば次ぎのような効果を有する。 The present invention has been described above with reference to embodiments, but the present invention has the following effects.
(1) 異方性付与に永久磁石体を用いるため、内壁
金型の小さなスペースにも組み込め、しかも多
極が可能である。(1) Since a permanent magnet is used to impart anisotropy, it can be incorporated into the small space of the inner wall mold, and multiple poles are possible.
(2) 電磁石で行う場合には、コイル発熱、絶縁、
電流容量スペースなどを堪案した設計が必要
で、操作や構造が複雑になるのに対し、本装置
は極めて簡単な機構となり、この結果１台のプ
レスに対して複数の粉末充填キヤビテイを設け
ることも可能となり生産性が向上する。(2) When using an electromagnet, coil heat generation, insulation,
This requires a design that considers the current capacity space, making the operation and structure complicated, but this device has an extremely simple mechanism, and as a result, it is possible to provide multiple powder filling cavities for one press. This also makes it possible to improve productivity.
(3) 湿式法では、これまで実現できなかつた円筒
状の半径方向に多極の磁力で放射方向の異方性
付与が可能であり、これにより、磁石の表面磁
束密度が大となり、30〜60％の性能向上が図
れ、モータにおけるトルクあるいは発電機にお
ける起電力を大幅に向上させることができる。(3) In the wet method, it is possible to impart radial anisotropy using multipolar magnetic force in the radial direction of a cylinder, which has not been possible until now.This increases the surface magnetic flux density of the magnet, and The performance can be improved by 60%, and the torque in the motor or the electromotive force in the generator can be significantly improved.
(4) 湿式法のため、長軸の永久磁石であつても、
軸方向の密度のバラツキなく製造でき、電子複
写機の現像ロール用の異方性永久磁石を一体構
造のものとして簡単に製造することができる。(4) Due to the wet method, even with long-axis permanent magnets,
It can be manufactured without variation in density in the axial direction, and an anisotropic permanent magnet for a developing roll of an electronic copying machine can be easily manufactured as a one-piece structure.
(5) また、本発明では内壁金型内に組込んだ永久
磁石は、内壁金型の軸方向と直角方向に着磁さ
れた４つ以上の永久磁石で、NS極が交互に内
壁金型の外周面に沿つて並ぶように配置された
ものであるので、各永久磁石の径方向内側の磁
極は互いに接近し、磁気的に短絡されたとほと
んど同様の状態となるので、外側のキヤビテイ
内に充分高い配向磁場を形成することができる
ため、径方向多極（４極以上）に高い異方性を
付与された成形体を容易に得ることができる。(5) In addition, in the present invention, the permanent magnets incorporated into the inner wall mold are four or more permanent magnets magnetized in a direction perpendicular to the axial direction of the inner wall mold, and the NS poles are alternately arranged in the inner wall mold. The radially inner magnetic poles of each permanent magnet are placed close to each other, creating a state almost similar to that of being magnetically short-circuited. Since a sufficiently high orientation magnetic field can be formed, a molded article with high anisotropy in radial multipoles (four or more poles) can be easily obtained.
第１図は、本発明における半径方向磁場の印加
を説明するためのモデル図、第２図は、本発明の
一実施例を示す図で、ａ図は縦断面図、ｂ図は横
断面図である。
１……外壁金型、２……内壁金型、３……永久
磁石、４……下パンチ、５……供給孔、６……
過孔、７……過装置、１０……キヤビテイ。
FIG. 1 is a model diagram for explaining the application of a radial magnetic field in the present invention, and FIG. 2 is a diagram showing an embodiment of the present invention, in which figure a is a longitudinal cross-sectional view and figure b is a cross-sectional view. It is. 1... Outer wall mold, 2... Inner wall mold, 3... Permanent magnet, 4... Lower punch, 5... Supply hole, 6...
Overhole, 7... Over device, 10... Cavity.
Claims (1)
型するフエライトスラリーの磁場中成型装置であ
つて、孔部を有する外壁金型と、該孔部に配置さ
れた上記外壁金型との間に円筒状のキヤビテイを
形成する内壁金型と、該円筒状のキヤビテイに半
径方向の磁力を作用させるように該内壁金型内に
その軸方向と直角方向に着磁された４つ以上の永
久磁石をNS極が交互に内壁金型の外周面に沿つ
て並ぶように配置して組み込まれた該４つ以上の
永久磁石と、上記円筒状キヤビテイにフエライト
粉末のスラリーを供給する機構と、該円筒状キヤ
ビテイに出入りする下パンチと、該キヤビテイの
下パンチと反対側で両金型に設置されたスラリー
中の液体の過のための過装置とを有すること
を特徴とするフエライトスラリーの磁場中成型装
置。1. A magnetic field molding device for ferrite slurry that performs pressure molding while applying a magnetic field in the radial direction of a cylindrical shape, in which an outer wall mold having a hole and the outer wall mold disposed in the hole are provided. An inner wall mold forming a cylindrical cavity, and four or more permanent magnets magnetized in the inner wall mold in a direction perpendicular to the axial direction of the inner wall mold so as to apply a radial magnetic force to the cylindrical cavity. a mechanism for supplying slurry of ferrite powder to the cylindrical cavity; Molding of ferrite slurry in a magnetic field, characterized by having a lower punch that enters and exits a shaped cavity, and a filtration device for filtration of liquid in the slurry, which is installed in both molds on the opposite side of the lower punch of the cavity. Device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57184369A JPS5972703A (en) | 1982-10-20 | 1982-10-20 | Molding device of ferrite slurry in magnetic field |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57184369A JPS5972703A (en) | 1982-10-20 | 1982-10-20 | Molding device of ferrite slurry in magnetic field |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5972703A JPS5972703A (en) | 1984-04-24 |
| JPS64808B2 true JPS64808B2 (en) | 1989-01-09 |
Family
ID=16152014
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57184369A Granted JPS5972703A (en) | 1982-10-20 | 1982-10-20 | Molding device of ferrite slurry in magnetic field |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5972703A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6455814A (en) * | 1987-08-26 | 1989-03-02 | Fuji Electrochemical Co Ltd | Manufacture of anisotropic bonding magnet |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS593245B2 (en) * | 1975-04-09 | 1984-01-23 | 日立金属株式会社 | Tojiki Oyobi Sonoseizohouhou |
| JPS55156309A (en) * | 1979-05-24 | 1980-12-05 | Matsushita Electric Ind Co Ltd | Magnetization of annular magnet |
| JPS5669805A (en) * | 1979-11-10 | 1981-06-11 | Tdk Corp | Manufacture of anisotropic plastic magnet |
-
1982
- 1982-10-20 JP JP57184369A patent/JPS5972703A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5972703A (en) | 1984-04-24 |
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