EP0255613B1 - Process for manufacturing bipolar or multipolar permanent magnets with a high magnetic energy density - Google Patents

Process for manufacturing bipolar or multipolar permanent magnets with a high magnetic energy density Download PDF

Info

Publication number
EP0255613B1
EP0255613B1 EP19870109822 EP87109822A EP0255613B1 EP 0255613 B1 EP0255613 B1 EP 0255613B1 EP 19870109822 EP19870109822 EP 19870109822 EP 87109822 A EP87109822 A EP 87109822A EP 0255613 B1 EP0255613 B1 EP 0255613B1
Authority
EP
European Patent Office
Prior art keywords
powder
process according
permanent magnets
magnetic
synthetic material
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.)
Revoked
Application number
EP19870109822
Other languages
German (de)
French (fr)
Other versions
EP0255613A3 (en
EP0255613A2 (en
Inventor
Hans E. Ing. Vogt
Valentin Dipl.-Ing. Tanach
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vogt Electronic AG
Original Assignee
Vogt Electronic AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6306662&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0255613(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Vogt Electronic AG filed Critical Vogt Electronic AG
Publication of EP0255613A2 publication Critical patent/EP0255613A2/en
Publication of EP0255613A3 publication Critical patent/EP0255613A3/en
Application granted granted Critical
Publication of EP0255613B1 publication Critical patent/EP0255613B1/en
Anticipated expiration legal-status Critical
Revoked legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/22—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces for producing castings from a slip
    • B22F3/225—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces for producing castings from a slip by injection molding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/22—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces for producing castings from a slip
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/06—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H01F1/08—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
    • H01F1/083—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together in a bonding agent
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/10—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure
    • H01F1/11—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure in the form of particles
    • H01F1/113—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials non-metallic substances, e.g. ferrites, e.g. [(Ba,Sr)O(Fe2O3)6] ferrites with hexagonal structure in the form of particles in a bonding agent
    • 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
    • H01F41/0273—Imparting anisotropy
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy

Definitions

  • the invention relates to a method for producing anisotropic permanent magnets with a high magnetic energy density.
  • the powder is pressed into a shaped body in a magnetic field that impresses the desired preferred direction, and the shaped body is then sintered.
  • high-density permanent magnets of various types can be produced with a preferred direction in the pressing direction or transversely thereto.
  • the known method for producing permanent magnets with a radial preferred direction is restricted to those with a low height / diameter ratio; otherwise, permanent magnets manufactured according to the known method with a radial preferred direction have only weak magnetic properties.
  • Pole-oriented ring magnets can also be produced by the known method, but in this case there are filling problems, poor orientation and cracks in the sintered parts, so that the application the known method is disadvantageous for this purpose.
  • the object of the invention is to achieve an economical, i.e. to create a method that is simple and can be carried out with little effort, which on the one hand permits in particular the multipole lateral anisotropy stamping but also the most varied types of anisotropy such as axial, radial, diametrical and on the other hand the high energy densities that can be achieved for the permanent magnets produced thereafter in particular produced by the known method mentioned in the first place, anisotropic magnets, eg with axial preferential direction, are usually obtained.
  • the method according to the invention can be used for the production of permanent magnets from barium or strontium ferrite powder, from metal alloy powder and also from rare earth magnet powder.

Description

Die Erfindung bezieht sich auf ein Verfahren zur Herstellung von anisotropen Dauermagneten mit hoher magnetischer Energiedichte.The invention relates to a method for producing anisotropic permanent magnets with a high magnetic energy density.

Zur Herstellung anisotroper Dauermagnete sind verschiedene Verfahren bekannt.Various methods are known for producing anisotropic permanent magnets.

Bei dem am meisten verwendeten bekannten Verfahren wird das Pulver in einem die gewünschte Vorzugsrichtung einprägenden Magnetfeld zu einem Formkörper verpreßt und der Formkörper anschließend gesintert. Auf diese Weise können eine hohe Energiedichte aufweisende Dauermagnete verschiedener Art mit Vorzugsrichtung in der Preßrichtung oder quer dazu hergestellt werden. Zum Herstellen von Dauermagneten mit radialer Vorzugsrichtung ist das bekannte Verfahren aber eingeschränkt auf solche mit niedrigem Höhe/Durchmesser-Verhältnis; ansonsten weisen nach dem bekannten Verfahren hergestellte Dauermagnete mit radialer Vorzugsrichtung nur schwache magnetische Eigenschaften auf. Nach dem bekannten Verfahren können auch polorientierte Ringmagnete hergestellt werden, doch ergeben sich in diesem Falle Füllungsprobleme, eine schwache Orientierung und Risse bei den gesinterten Teilen, so daß die Anwendung des bekannten Verfahrens zu diesem Zweck nachteilig ist.In the most frequently used known method, the powder is pressed into a shaped body in a magnetic field that impresses the desired preferred direction, and the shaped body is then sintered. In this way, high-density permanent magnets of various types can be produced with a preferred direction in the pressing direction or transversely thereto. However, the known method for producing permanent magnets with a radial preferred direction is restricted to those with a low height / diameter ratio; otherwise, permanent magnets manufactured according to the known method with a radial preferred direction have only weak magnetic properties. Pole-oriented ring magnets can also be produced by the known method, but in this case there are filling problems, poor orientation and cracks in the sintered parts, so that the application the known method is disadvantageous for this purpose.

Ein anderes bekanntes Verfahren zur Herstellung von anisotropen Dauermagneten ist das Strangziehen in Verbindung mit einem nachträglichen Sinterprozess. Bei diesem Verfahren wird mechanisch eine gewisse radiale Anisotropie erzeugt, aber die resultierende Energiedichte ist nur etwas größer als bei den isotropen Magneten.Another known method for producing anisotropic permanent magnets is the continuous drawing in connection with a subsequent sintering process. This process creates some radial anisotropy mechanically, but the resulting energy density is only slightly greater than that of the isotropic magnets.

Ein weiteres bekanntes Verfahren zur Herstellung von anisotropen Dauermagneten aus Magnetpulvern ist die Bindung der Pulver mit Kunststoff und die Bearbeitung der Masse durch Pressen, Spritzen, Kalandrieren oder Extrudieren und Einprägung der Vorzugsrichtung mit mechanischen oder magnetischen Methoden, wobei der Kunststoff im fertigen Magneten verbleibt. Die so erhaltenen anisotropen kunststoffgebundenen Dauermagnete zeigen in der Regel bessere Eigenschaften als die isotropen Dauermagnete aus dem gleichen magnetischen Werkstoff und können auch verschiedene Vorzugsrichtungen wie axial, diametral, radial sowie mehrpolig lateral am Umfang aufweisen. Durch die Einbettung des Magnetpulvers in dem im fertigen Magneten verbleibenden Kunststoff ist aber die Energiedichte dieser Magnete begrenzt, und die hohen Werte, die bei den entsprechenden, nach dem eingangs besprochenen bekannten Verfahren hergestellten gesinterten Dauermagneten erzielbar sind, können nie erreicht werden.Another known method for producing anisotropic permanent magnets from magnetic powders is the binding of the powders with plastic and the processing of the mass by pressing, spraying, calendering or extruding and impressing the preferred direction using mechanical or magnetic methods, the plastic remaining in the finished magnet. The anisotropic plastic-bonded permanent magnets obtained in this way generally have better properties than the isotropic permanent magnets made of the same magnetic material and can also have different preferred directions such as axial, diametrical, radial and multi-pole laterally on the circumference. By embedding the magnetic powder in the plastic remaining in the finished magnet, however, the energy density of these magnets is limited, and the high values that can be achieved with the corresponding sintered permanent magnets produced by the known methods discussed at the beginning can never be achieved.

Zur Herstellung von Dauermagneten aus Hartferrit-Pulver mit radialer Anisotropie ist schließlich noch ein weiteres Verfahren bekannt geworden, bei dem das Ferrit-Pulver mit einem Kunststoff gemischt, dann in Folien unter Magnetfeld kalandriert, dann auf einem Dorn unter Druck und Magnetfeld gewickelt, dann der Kunststoff beseitig und zuletzt gesintert wird. Die für die so hergestellten Dauermagnete angegebenen magnetischen Werte sind gut, aber das bekannte Verfahren ist kompliziert und sehr aufwendig und nur für radiale Vorzugsrichtung der Magnete geeignet.Another method has finally become known for producing permanent magnets from hard ferrite powder with radial anisotropy, in which the ferrite powder is mixed with a plastic, then calendered in foils under a magnetic field, then wound on a mandrel under pressure and magnetic field, then the Plastic is removed and sintered last. The magnetic values given for the permanent magnets produced in this way are good, but the known method is complicated and very expensive and only suitable for the radial preferred direction of the magnets.

Im Zusammenhang mit der Herstellung von Formteilen aus Legierungen (DE-A-3120501) ist es bekannt, ein Pulver der Legierung oder ein Gemisch aus Pulvern der Legierungskomponenten mit Hilfe von Thermoplasten, Duroplasten und Gleitmitteln zu einer spritzfähigen Granulat-Masse aufzubereiten, die spritzfähige Granulatmasse durch Spritzguß zu einem Formteil zu bearbeiten, anschließend den Kunststoff durch eine Wärmebehandlung bis 600° C unter Schutzgas zu entfernen und schließlich den so erhaltenen Formteil zu sintern. Bei diesem bekannten Verfahren kommt es nicht darauf an, als Endprodukt einen Dauermagneten zu erhalten, das z.B. eine bestimmte Vorzugsrichtung hinsichtlich bestimmter physikalischer Eigenschaften aufweist, d.h. anisotrop ist. Es wird lediglich angestrebt, ein Endprodukt mit insgesamt guten mechanischen Eigenschaften, insbesondere hinsichtlich der Schwingungsfestigkeit, zu erhalten.In connection with the production of molded parts from alloys (DE-A-3120501), it is known to prepare a powder of the alloy or a mixture of powders of the alloy components with the aid of thermoplastics, thermosets and lubricants to form an injectable granulate mass, the injectable granulate mass to process by injection molding into a molded part, then to remove the plastic by heat treatment up to 600 ° C under protective gas and finally to sinter the molded part thus obtained. In this known method it is not important to obtain a permanent magnet as the end product, which e.g. has a certain preferred direction with regard to certain physical properties, i.e. is anisotropic. The only aim is to obtain an end product with good mechanical properties overall, in particular with regard to the vibration resistance.

Ausgehend von dem vorgenannten Stand der Technik liegt der Erfindung die Aufgabe zugrunde, ein wirtschaftliches, d.h. einfach und mit einem geringen Aufwand durchführbares, Verfahren zu schaffen, das einerseits insbesondere die mehrpolige laterale Anisotropieprägung aber auch die verschiedensten Arten von Anisotropien wie axial, radial, diametral zuläßt und mit dem andererseits für die danach hergestellten Dauermagnete die hohen Energiedichten erreichbar sind, die bei insbesondere nach dem an erster Stelle genannten bekannten Verfahren hergestellten anisotropen Magneten, z.B. mit axialer Vorzugsrichtung, üblicherweise erhalten werden.On the basis of the aforementioned prior art, the object of the invention is to achieve an economical, i.e. to create a method that is simple and can be carried out with little effort, which on the one hand permits in particular the multipole lateral anisotropy stamping but also the most varied types of anisotropy such as axial, radial, diametrical and on the other hand the high energy densities that can be achieved for the permanent magnets produced thereafter in particular produced by the known method mentioned in the first place, anisotropic magnets, eg with axial preferential direction, are usually obtained.

Die vorstehende Aufgabe wird durch die im Patentanspruch 1 genannten Merkmale gelöst.The above object is achieved by the features mentioned in claim 1.

Das erfindungsgemäße Verfahren umfaßt neben den im Bedarfsfalle üblichen, bei allen bekannten Herstellungsverfahren von Dauermagneten aus Magnetpulverwerkstoff zur Anwendung gelangenden Maßnahmen der mechanischen Nachbearbeitung und Aufmagnetisierung mit Rücksicht auf die eingeprägten Pole im Anschluß an die Herstellung des eigentlichen Magnetkörpers nur drei sehr einfach durchführbare Verfahrensstufen, nämlich

  • die Herstellung des Granulats,
  • das thermoplastische Spritzen des Granulats im Magnetfeld in die gewünschte Form, wobei die im Endzustand gewünschten Vorzugsrichtungen eingeprägt werden, und
  • das Sintern der gesprizten Teile in der üblichen Weise, ohne vorheriges Entfernen des Kunststoffs aus dem Formkörper.
The process according to the invention comprises, in addition to the usual, if necessary, in all known production processes Measures of mechanical post-processing and magnetization used by permanent magnets made of magnetic powder material with regard to the embossed poles following the manufacture of the actual magnetic body are only three very simple process steps, namely
  • the production of the granulate,
  • thermoplastic injection of the granules into the desired shape in the magnetic field, the preferred directions desired in the final state being impressed, and
  • the sintering of the molded parts in the usual manner without first removing the plastic from the molded body.

Es ist überraschend, daß die während des Spritzvorgangs eingeprägten gewünschten Vorzugsrichtungen ohne besondere zusätzliche Maßnahmen vor dem Sintern durch das Sintern des vorher in einem einfachen Spritzvorgang erhaltenen, den Kunststoff noch enthaltenden Formkörpers nicht beeinträchtigt wird, so daß die magnetischen Eigenschaften entlang den beim Spritzen vorhandenen magnetischen Wegen eine vollständige Anisotropie aufweisen. Die magnetischen Werte liegen ähnlich den anisotropen gepreßten und gesinterten Magneten mit axialer Anisotropie, die nach dem oben an erster Stelle genannten bekannten Verfahren hergestellt sind.It is surprising that the desired preferred directions impressed during the spraying process are not impaired without any special additional measures prior to sintering by the sintering of the shaped body which was previously obtained in a simple spraying process and which still contains the plastic, so that the magnetic properties along the magnetic properties present during spraying Because of complete anisotropy. The magnetic values are similar to the anisotropic pressed and sintered magnets with axial anisotropy, which are produced by the known method mentioned above in the first place.

Das erfindungsgemäße Verfahren kann zur Herstellung von Dauermagneten aus Barium- oder Strontium-Ferritpulver, aus Metallegierungspulver sowie auch aus Seltenerd-Magnetpulvern angewendet werden.The method according to the invention can be used for the production of permanent magnets from barium or strontium ferrite powder, from metal alloy powder and also from rare earth magnet powder.

Die Unteransprüche betreffen bevorzugte Ausgestaltungen des Verfahrens gemäß Patentanspruch 1.The subclaims relate to preferred configurations of the method according to claim 1.

Beispielexample

Aus Sr-Ferritpulver durch Pressen hergestellte Dauermagnete mit axialer Anisotropie zeigen folgende magnetische Eigenschaften:

Remanenz Br
= 390 mT
Koerzitivfeldstärke BHc
= 265 kA/m
Koerzitivfeldstärke JHc
= 272 kA/m
Max. Energiedichte (BH)max
= 28 kJ/m³
Permanent magnets with axial anisotropy produced from Sr ferrite powder by pressing show the following magnetic properties:
Remanence B r
= 390 mT
Coercive field strength B H c
= 265 kA / m
Coercive field strength J H c
= 272 kA / m
Max. Energy density (BH) max
= 28 kJ / m³

Aus gleichem Ferritpulver mit Kunststoff gemischt (Verhältnis 88 Gew% Ferritpulver/12 Gew% Kunststoff) und granuliert, werden Ringmagnete mit den Abmessungen (im Endzustand) Da = 13 mm, Di = 8 mm, und H = 20 mm unter Magnetfeld mit Einprägung von 12 Polen am Ringumfang gespritzt und dann gesintert und geschliffen. Die magnetischen Eigenschaften sind die gleichen wie vorstehend angegeben.From the same ferrite powder mixed with plastic (ratio 88% by weight ferrite powder / 12% by weight plastic) and granulated, ring magnets with the dimensions (in the final state) Da = 13 mm, Di = 8 mm, and H = 20 mm under a magnetic field with an impression of 12 poles injection molded around the ring circumference and then sintered and ground. The magnetic properties are the same as stated above.

Außerdem wird nach 12-poliger Magnetisierung am Umfang der Ringmagnete eine Induktion von ca. 200 mT gemessen.In addition, an induction of approx. 200 mT is measured on the circumference of the ring magnets after 12-pole magnetization.

Claims (9)

  1. Process for the manufacture of anisotropic permanent magnets with high energy density from powder of a magnetic material, comprising the sequence in which
    a) the powder is mixed with a suitable synthetic material under application of heat,
    b) the compound obtained in the process step (a) is granulated,
    c) the granulate obtained in the process step (b) is thermoplastically injection-moulded into the desired form under loading by one or several magnetic fields for the impressing of the desired preferential direction(s), and
    d) a sintering process of the moulded body obtained in the process step (c) with the synthetic material contained therein is undertaken.
  2. Process according to claim 1, characterised thereby that the sintered moulded body is mechanically finished.
  3. Process according to claim 1 or 2, characterised thereby that the sintered moulded body is magnetised corresponding to the pole impressing.
  4. Process according to one of the preceding claims, characterised thereby that barium ferrite powder, strontium ferrite powder, metallic alloy powder or a rare earth magnetic powder is used as magnetic powder.
  5. Process according to claim 4, characterised thereby that the metallic alloy powder has Al, Ni and Co.
  6. Process according to claim 4, characterised thereby that the rare earth magnetic powder has Sm, Nd.
  7. Process according to one of the preceding claims, characterised thereby that the ratio by weight of magnetic powder to synthetic material amounts to 1:1 to 20:1.
  8. Process according to one of the preceding claims, characterised thereby, that the synthetic material is polyamide, polyurethane, polypropylene, polyethylene or polystyrene.
  9. Process according to one of the preceding claims, characterised thereby that the preferential direction is impressed to be axially, diametrally, radially, laterally unipolar or multipolar.
EP19870109822 1986-08-04 1987-07-08 Process for manufacturing bipolar or multipolar permanent magnets with a high magnetic energy density Revoked EP0255613B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19863626360 DE3626360C2 (en) 1986-08-04 1986-08-04 Manufacturing process for two-pole and multi-pole permanent magnets with high magnetic energy density
DE3626360 1986-08-04

Publications (3)

Publication Number Publication Date
EP0255613A2 EP0255613A2 (en) 1988-02-10
EP0255613A3 EP0255613A3 (en) 1988-07-13
EP0255613B1 true EP0255613B1 (en) 1992-05-13

Family

ID=6306662

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19870109822 Revoked EP0255613B1 (en) 1986-08-04 1987-07-08 Process for manufacturing bipolar or multipolar permanent magnets with a high magnetic energy density

Country Status (2)

Country Link
EP (1) EP0255613B1 (en)
DE (1) DE3626360C2 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0540504B1 (en) * 1988-02-29 1995-05-31 Matsushita Electric Industrial Co., Ltd. Method for making a resin bonded magnet article
US5049053A (en) * 1988-08-18 1991-09-17 Hitachi Metals, Ltd. Metal mold for molding anisotropic permanent magnets
DE4420318C2 (en) * 1994-06-11 1996-04-11 Schulman A Gmbh Polymer-based composition for the production of magnetic and magnetizable moldings
DE4434471C1 (en) * 1994-09-27 1996-03-28 Bosch Gmbh Robert Process for the production of moldings from hard ferrites
DE102008052804A1 (en) * 2008-10-22 2010-04-29 Windhorst Beteiligungsgesellschaft Mbh Magnetic rotary encoder for detection of angle- or rotation of shaft in e.g. household appliance, has front side at which angle sensors are fixedly arranged on rotational axis, where encoder is made of anisotropic hard ferrite
DK2632809T3 (en) 2010-10-27 2016-02-15 Intercontinental Great Brands Llc MAGNETIC closable PRODUCT RECEIVING PACKAGING
US20170100862A1 (en) * 2015-10-09 2017-04-13 Lexmark International, Inc. Injection-Molded Physical Unclonable Function
US10035095B2 (en) 2016-03-04 2018-07-31 General Electric Company Diverted pulse jet cleaning device and system

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1284531B (en) * 1957-04-27 1968-12-05 Baermann Max Method and device for the production of plastic-bonded anisotropic permanent magnets
DE1464249A1 (en) * 1963-11-16 1969-02-20 Leyman Corp Process for the production of permanent magnets
DE1764279A1 (en) * 1968-05-08 1972-01-27 Magnetfab Bonn Gmbh Process for the production of permanent magnets from anisotropic permanent magnet powder
DE2401934C3 (en) * 1974-01-16 1981-05-14 Fuji Electrochemical Co., Ltd., Tokyo Method of manufacturing an anisotropic ferrite magnet
DE3021607A1 (en) * 1980-06-09 1981-12-17 Philips Patentverwaltung Gmbh, 2000 Hamburg Permanent magnet rotor for electrical machines - esp. bicycle dynamo, using ferrite magnet which is either sintered or bonded with polymer, and is joined to stub axle
DE3047701A1 (en) * 1980-12-18 1982-07-15 Magnetfabrik Bonn Gmbh Vorm. Gewerkschaft Windhorst, 5300 Bonn METHOD FOR PRODUCING ANISOTROPAL PERMANENT MAGNETS AND TUBULAR PERMANENT MAGNETS PRODUCED THEREFORE
DE3120501C2 (en) * 1981-05-22 1983-02-10 MTU Motoren- und Turbinen-Union München GmbH, 8000 München "Process and device for the production of molded parts"

Also Published As

Publication number Publication date
EP0255613A3 (en) 1988-07-13
DE3626360C2 (en) 1995-06-22
DE3626360A1 (en) 1988-02-11
EP0255613A2 (en) 1988-02-10

Similar Documents

Publication Publication Date Title
EP1444706B1 (en) Inductive component and method for producing same
DE19728418C2 (en) Manufacturing process for anisotropic resin-bonded magnets
DE4420318C2 (en) Polymer-based composition for the production of magnetic and magnetizable moldings
DE2756626C2 (en) "Process for the production of a rotor for an electrical machine"
DE1538731A1 (en) Small electric machine
DE10128004A1 (en) Wound inductive device has soft magnetic core of ferromagnetic powder composite of amorphous or nanocrystalline ferromagnetic alloy powder, ferromagnetic dielectric powder and polymer
DE10050703A1 (en) Production of a rotating electromagnetic body with regions of different magnetic properties comprises compressing a soft magnetic powder and a permanent magnet material and partially sintering
EP0255613B1 (en) Process for manufacturing bipolar or multipolar permanent magnets with a high magnetic energy density
DE3047701A1 (en) METHOD FOR PRODUCING ANISOTROPAL PERMANENT MAGNETS AND TUBULAR PERMANENT MAGNETS PRODUCED THEREFORE
DE102011105867A1 (en) Rotor for permanent magnetically excited electrical machines e.g. electromotor, has rotor main structure comprising several magnetic poles that are provided corresponding to number of projections provided in ferromagnetic baffle
DE112011104619T5 (en) Arctic magnet with polar anisotropic orientation and method and form of formation for its manufacture
DE10112464A1 (en) Magnet, process for its manufacture and motor using it
DE19925322B4 (en) Extrusion-molded magnetic body made of samarium-iron-nitrogen magnetic particles
DE102011105324A1 (en) Injection molding tool for manufacturing ring magnet that is molded on shaft, has orientation magnets aligning magnetic material particles in molding material, where magnets are aligned in accordance with two-piece halbach arrangement
DE19953650A1 (en) Process for the production and storage of individual magnetic components and their assembly for the production of miniaturized magnet systems and such magnet systems
DE4021990C2 (en) Process for manufacturing a permanent magnet
DE4228519B4 (en) Process for the production of plastic-bonded anisotropic permanent magnet moldings
DE4228520C2 (en) Process for the production of thin-walled plastic-bonded permanent magnet molded parts, such as shell magnets
DE10246719A1 (en) Manufacture of multipole ring magnet from rare-earth alloy by pressing powder of magnetically oriented material in ring-shape using press cavity of die, orienting and sintering
WO2007045545A1 (en) Rotor for an electric machine
EP3373418A1 (en) Electromechanical component
DE102021006524B4 (en) Method of manufacturing a raw magnet
EP1022929B1 (en) Loudspeaker with a jacketed magnetic core
DE102021201414A1 (en) Process for producing a raw magnet from a magnetic raw material
DE10316176A1 (en) Production of a cylindrical coded element comprises molding an annular rubber element, placing on the pot section of a lower metal mold, pressing the rubber element to fill a cavity, cutting away the molded sections, and magnetizing

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): FR GB IT NL

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

RHK1 Main classification (correction)

Ipc: H01F 7/06

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): FR GB IT NL

17P Request for examination filed

Effective date: 19881229

17Q First examination report despatched

Effective date: 19910406

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): FR GB IT NL

ITF It: translation for a ep patent filed

Owner name: BUGNION S.P.A.

ET Fr: translation filed
ITTA It: last paid annual fee
GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: SIEMENS AKTIENGESELLSCHAFT, BERLIN UND MUENCHEN

Effective date: 19930210

NLR1 Nl: opposition has been filed with the epo

Opponent name: SIEMENS AG.

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19950630

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19950710

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19950731

Year of fee payment: 9

RDAG Patent revoked

Free format text: ORIGINAL CODE: 0009271

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: PATENT REVOKED

27W Patent revoked

Effective date: 19960219

GBPR Gb: patent revoked under art. 102 of the ep convention designating the uk as contracting state

Free format text: 960219

NLR2 Nl: decision of opposition