EP0794540A1 - Small bistable magnet - Google Patents
Small bistable magnet Download PDFInfo
- Publication number
- EP0794540A1 EP0794540A1 EP97102643A EP97102643A EP0794540A1 EP 0794540 A1 EP0794540 A1 EP 0794540A1 EP 97102643 A EP97102643 A EP 97102643A EP 97102643 A EP97102643 A EP 97102643A EP 0794540 A1 EP0794540 A1 EP 0794540A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- armature
- coil
- permanent magnet
- bistable
- magnet
- 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.)
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/06—Electromagnets; Actuators including electromagnets
- H01F7/08—Electromagnets; Actuators including electromagnets with armatures
- H01F7/16—Rectilinearly-movable armatures
- H01F7/1607—Armatures entering the winding
- H01F7/1615—Armatures or stationary parts of magnetic circuit having permanent magnet
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- E—FIXED CONSTRUCTIONS
- E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
- E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
- E05B47/00—Operating or controlling locks or other fastening devices by electric or magnetic means
- E05B47/0001—Operating or controlling locks or other fastening devices by electric or magnetic means with electric actuators; Constructional features thereof
- E05B47/0002—Operating or controlling locks or other fastening devices by electric or magnetic means with electric actuators; Constructional features thereof with electromagnets
- E05B47/0003—Operating or controlling locks or other fastening devices by electric or magnetic means with electric actuators; Constructional features thereof with electromagnets having a movable core
- E05B47/0004—Operating or controlling locks or other fastening devices by electric or magnetic means with electric actuators; Constructional features thereof with electromagnets having a movable core said core being linearly movable
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- E—FIXED CONSTRUCTIONS
- E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
- E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
- E05B47/00—Operating or controlling locks or other fastening devices by electric or magnetic means
- E05B47/06—Controlling mechanically-operated bolts by electro-magnetically-operated detents
- E05B47/0611—Cylinder locks with electromagnetic control
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/06—Electromagnets; Actuators including electromagnets
- H01F7/08—Electromagnets; Actuators including electromagnets with armatures
- H01F7/16—Rectilinearly-movable armatures
- H01F2007/1669—Armatures actuated by current pulse, e.g. bistable actuators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F7/00—Magnets
- H01F7/06—Electromagnets; Actuators including electromagnets
- H01F7/08—Electromagnets; Actuators including electromagnets with armatures
- H01F7/121—Guiding or setting position of armatures, e.g. retaining armatures in their end position
- H01F7/122—Guiding or setting position of armatures, e.g. retaining armatures in their end position by permanent magnets
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H51/00—Electromagnetic relays
- H01H51/22—Polarised relays
- H01H51/2209—Polarised relays with rectilinearly movable armature
- H01H2051/2218—Polarised relays with rectilinearly movable armature having at least one movable permanent magnet
Definitions
- the invention relates to a bistable small magnet, comprising an armature which is arranged in an axially movable arrangement in a coil arrangement and a fixed pole piece arranged on or in one end of the coil, the armature being drawn into the coil tube and against the pole piece when the coil is suitably energized is and the armature is provided with an axially polarized permanent magnet, which also holds the armature in the drawn position when de-energized and where, when the coil is suitably energized, the adhesive force of the permanent magnet is neutralized and the armature is moved into its starting position (start of stroke) by the force of a spring position) is moved.
- Such small magnets are used in devices with locking or adjustment functions. They are used, for example, to generate mechanical yes-no statements, to drive small levers and parts in precision engineering applications, to control diaphragms in optical systems or to control slit diaphragms in gas and oil burners.
- bistable small magnets are also used in battery-operated systems, such as. B. in the remote controlled locking and unlocking of locking devices and cylinder locks. In such applications, the small magnets must switch with very low power consumption, so that, for. B. the battery life in battery-operated devices is as large as possible.
- a bistable magnet is known from DE 30 19 418 A1, in which a submersible armature is attracted by the supply of an operating current against the force of a spring and is held permanently magnetically and after application of a Counter current is moved back to neutralize the permanent magnetic force effect.
- the permanent magnet for generating the permanent magnetic adhesive force lies entirely in the interior of the coil space. During the working stroke, it is additionally magnetized by the working current and demagnetized by the extinguishing current to return the armature to the starting position. This requires permanent magnets with a very low coercive field strength, although the required remagnetization power is still very high. Scattering of the magnetic material and scattering in the control currents also lead to very different functions / switching times.
- the anchor-cone configuration is also unfavorable for long strokes, since there is too little initial lift force and permanent adhesive force.
- the invention is therefore based on the object of designing a bistable magnet of the type mentioned in such a way that it can be switched over quickly and safely with minimal control power, but long travel distances and high initial stroke forces as well as high permanent magnetic holding forces should also be present.
- the armature has a soft magnetic auxiliary connection for the permanent magnet and that in the stroke start position the center of the permanent magnet - seen in the axial direction - is approximately in the plane of the coil start (the end face of the coil).
- bistable magnet can be made very small overall and can be reversed quickly and safely. There are only very few for reversing Services required, the changeover times achieved are very small and the actuating forces of the armature are nevertheless relatively large.
- the power requirement is z. B. only about 15% compared to an execution of the armature without permanent magnet arrangement.
- the magnet-specific parts and materials With appropriate design of the magnet-specific parts and materials, further increases in the responsiveness or the efficiency of the small magnet are possible.
- the small magnet shown in FIGS. 1 and 2 consists essentially of a soft magnetic magnet yoke 1, in which an excitation coil 2 with an armature axially movable in its coil body 3, which is designed as a plunger armature, is installed. At one end of the coil or the coil body, a pole piece 5 is provided, against which the armature is pulled when the current is directed accordingly. A permanent magnet 6 is inserted into the armature 4. This permanent magnet is axially magnetized, as is shown by the identification of the poles with N and S.
- the permanent magnet is designed as an annular magnet, through the middle of which a section 7 of the soft magnetic armature runs. This section acts as a soft magnetic parallel branch.
- a spring 8 On the upper end of the armature 4 there is a spring 8, which is provided here as a truncated cone compression spring with a progressive characteristic. This spring is held or supported in a centering or mounting recess 9 in the front end of the bobbin 3 and acts against a shoulder 10 on the armature.
- This approach is preferably formed by snapping a locking washer onto the anchor. With this approach, a stop or a stroke limitation for the armature in its initial stroke position is realized simultaneously in connection with the correspondingly designed magnetic yoke.
- the armature - driven by the spring - is pushed until the stop is at the front end of the magnetic yoke.
- the lower end of the armature 4 is provided with a truncated cone 12, preferably produced by turning, the larger diameter of the truncated cone being at the outer end of the armature.
- the pole piece 5 has a cylindrical recess 13 into which this truncated cone is immersed when the armature is tightened, a push neck 14 being formed through the recess.
- the push neck is preferably designed conically on its outside, the thinner end of the push neck then being located at its opening.
- the truncated cone 12 of the anchor and the length of the push neck 14 are matched to one another, the height of the truncated cone roughly corresponding to the length of the push neck.
- the position of the permanent magnet within the armature is provided in such a way that when the armature starts at the start of the stroke (see FIG. 1) Pol "is immersed in the coil 2 and the other Pol "is outside the effective copper winding, ie in front of the end face 15 of the coil. It is preferably provided that the center of the permanent magnet is approximately in the plane of the coil end face. 1 and 2 show, the armature 4 is guided on the one hand in the coil body 3 and on the other hand via an armature tap or plunger 16 in a non-magnetic bearing 17. Instead of a small, separate bearing 17, an inexpensive non-magnetic bearing cover 22, in which a through hole forms the bearing point, can optionally also be used, as shown in FIG. 7.
- the polarity reversal of the electromagnetic field can optionally also be carried out by means of a second excitation coil, provided, for. B. the polarity of the coil current should not be reversed.
- the magnet arrangement described above, in conjunction with the spring 8, represents a bistable actuator which can be quickly switched to the other armature end position with short, low-power control pulses, in which it remains without power.
- the soft magnetic yoke 1 is formed by a non-magnetic yoke, such as a plastic injection molded part, including the bearing 17. It has been shown that the basic function of the magnet is nevertheless present.
- armature 4 with differently inserted permanent magnets 6 are shown. All armatures have the common feature that an axially magnetized permanent magnet is located within the armature and that a soft magnetic shunt is provided.
- the armature is provided with an annular groove in which an annular permanent magnet 6 is inserted.
- the middle or section 7 of the armature forms the shunt.
- the permanent magnet can optionally also be introduced into the armature by extrusion coating of a plastic-bonded permanent magnet material
- the armature is provided with a recess 18 into which a permanent magnet 6 in the form of a segment of a circle is inserted.
- the armature section 7 present next to the permanent magnet forms the soft magnetic shunt.
- Fig. 5 is provided that it is assembled from two parts. One part is provided with a recess 19 into which the permanent magnet 6 is inserted. The annular wall 20, which is formed by the recess, then forms the soft magnetic shunt.
- FIG. 6 shows an armature 4, into which a permanent magnet 6 with the same diameter as the armature itself is inserted.
- the soft magnetic shunt is formed by a slid-on, thin sleeve 21 made of soft magnetic material or, if necessary, it can also be provided that the armature and permanent magnet surface is provided with a galvanically applied, soft magnetic coating.
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Electromagnets (AREA)
- Reciprocating, Oscillating Or Vibrating Motors (AREA)
- Permanent Field Magnets Of Synchronous Machinery (AREA)
Abstract
Description
Die Erfindung betrifft einen bistabilen Kleinmagneten, umfassend einen Anker, der in einer Spulenanordnung axial beweglich angeordnet ist und ein an bzw. in einem Ende der Spule angeordnetes festes Polstück, wobei der Anker bei entsprechender Bestromung der Spule in dessen Spulenrohr hinein und gegen das Polstück gezogen wird und wobei der Anker mit einem axial polarisierten Permanentmagneten versehen ist, der den Anker in der angezogenen Stellung auch stromlos festhält und wobei bei entsprechend gerichteter Bestromung der Spule die Haftkraft des Permanentmagneten neutralisiert wird und der Anker durch die Kraft einer Feder in seine Ausgangslage (Hubanfangs-stellung) bewegt wird.The invention relates to a bistable small magnet, comprising an armature which is arranged in an axially movable arrangement in a coil arrangement and a fixed pole piece arranged on or in one end of the coil, the armature being drawn into the coil tube and against the pole piece when the coil is suitably energized is and the armature is provided with an axially polarized permanent magnet, which also holds the armature in the drawn position when de-energized and where, when the coil is suitably energized, the adhesive force of the permanent magnet is neutralized and the armature is moved into its starting position (start of stroke) by the force of a spring position) is moved.
Derartige Kleinmagnete werden in Geräten mit Verriegelungs- oder Verstellfunktionen eingesetzt. Sie dienen beispielsweise der Erzeugung mechanischer ja-nein- Aussagen, dem Antrieb von kleinen Hebeln und Teilen in feinwerktechnischen Anwendungen, der Blendensteuerung in optischen Systemen oder der Steuerung von Schlitzblenden in Gas- und Ölbrennern. Solche bistabilen Kleinmagnete werden auch in batteriebetriebenen Systemen eingesetzt, wie z. B. bei der ferngesteuerten Ver- und Entriegelung von Schließvorrichtungen und Zylinderschlössern. Bei derartigen Anwendungen müssen die Kleinmagnete mit sehr geringer Leistungsaufnahme umschalten, damit z. B. die Batterie-Lebensdauer bei batteriebetriebenen Einrichtungen möglichst groß ist.Such small magnets are used in devices with locking or adjustment functions. They are used, for example, to generate mechanical yes-no statements, to drive small levers and parts in precision engineering applications, to control diaphragms in optical systems or to control slit diaphragms in gas and oil burners. Such bistable small magnets are also used in battery-operated systems, such as. B. in the remote controlled locking and unlocking of locking devices and cylinder locks. In such applications, the small magnets must switch with very low power consumption, so that, for. B. the battery life in battery-operated devices is as large as possible.
Aus der DE 30 19 418 A1 ist ein bistabiler Magnet bekannt, bei dem ein Tauchanker durch Zufuhr eines Arbeitsstromes gegen die Kraft einer Feder angezogen und permanentmagnetisch gehalten und nach Anlegen eines Gegenstroms zur Neutralisierung der permanentmagnetischen Kraftwirkung zurückbewegt wird.
Bei der bekannten Anordnung liegt der Permanentmagnet zur Erzeugung der permanentmagnetischen Haftkraft vollständig im Inneren des Spulenraumes. Er wird beim Arbeitshub durch den Arbeitsstrom zusätzlich magnetisiert und durch den Löschstrom zur Rückkehr des Ankers in die Ausgangslage entmagnetisiert. Dazu sind Permanentmagnete mit sehr geringer Koerzitivfeldstärke nötig, wobei dennoch die erforderliche Ummagnetisierungsleistung sehr hoch ist. Auch führen Streuungen des Magnetmaterials und Streuungen in den Steuerströmen zu sehr unterschiedlichen Funktionen / Schaltzeiten.
Bei der bekannten Anordnung ist die Anker-Konus-Konfiguration außerdem für lange Hubwege ungünstig, da eine zu geringe Hubanfangskraft sowie permanente Haftkraft vorhanden sind.A bistable magnet is known from DE 30 19 418 A1, in which a submersible armature is attracted by the supply of an operating current against the force of a spring and is held permanently magnetically and after application of a Counter current is moved back to neutralize the permanent magnetic force effect.
In the known arrangement, the permanent magnet for generating the permanent magnetic adhesive force lies entirely in the interior of the coil space. During the working stroke, it is additionally magnetized by the working current and demagnetized by the extinguishing current to return the armature to the starting position. This requires permanent magnets with a very low coercive field strength, although the required remagnetization power is still very high. Scattering of the magnetic material and scattering in the control currents also lead to very different functions / switching times.
In the known arrangement, the anchor-cone configuration is also unfavorable for long strokes, since there is too little initial lift force and permanent adhesive force.
Der Erfindung liegt somit die Aufgabe zugrunde, einen bistabilen Magneten der eingangs genannten Art dahingehend auszubilden, daß dieser bei minimaler Steuerleistung schnell und sicher umgeschaltet werden kann, wobei aber auch lange Hubwege und hohe Hubanfangskräft sowie hohe permanentmagnetische Haftkräfte vorhanden sein sollen.The invention is therefore based on the object of designing a bistable magnet of the type mentioned in such a way that it can be switched over quickly and safely with minimal control power, but long travel distances and high initial stroke forces as well as high permanent magnetic holding forces should also be present.
Diese Aufgabe wird dadurch gelöst, daß der Anker einen weichmagnetischen Nebenanschluß für den Permanentmagneten aufweist und daß bei Hubanfangsstellung die Mitte des Permanentmagneten - in axialer Richtung gesehen - sich etwa in der Ebene des Spulenanfangs (der Stirnfläche der Spule) befindet.This object is achieved in that the armature has a soft magnetic auxiliary connection for the permanent magnet and that in the stroke start position the center of the permanent magnet - seen in the axial direction - is approximately in the plane of the coil start (the end face of the coil).
Vorteilhafte Ausgestaltungen der Erfindung sind in den Ansprüchen 2 bis 10 angegeben.Advantageous embodiments of the invention are specified in
Die mit der Erfindung erzielten Vorteile bestehen insbesondere darin, daß der bistabile Magnet insgesamt sehr klein ausgebildet und dabei schnell und sicher umgesteuert werden kann. Dabei sind zur Umsteuerung nur sehr geringe Leistungen nötig, wobei die erzielten Umsteuerzeiten sehr klein und die Betätigungskräfte des Ankers dennoch relativ groß sind.The advantages achieved by the invention consist in particular in that the bistable magnet can be made very small overall and can be reversed quickly and safely. There are only very few for reversing Services required, the changeover times achieved are very small and the actuating forces of the armature are nevertheless relatively large.
Durch die erfindungsgemäße Ausbildung des Ankers des Kleinmagneten liegt der Leistungsbedarf z. B. nur noch bei ca. 15 % gegenüber einer Ausführung des Ankers ohne Permanentmagnetanordnung. Bei entsprechender konstruktiver Auslegung der magnetspezifischen Teile und Materialien sind noch weitere Steigerungen der Ansprechempfindlichkeit bzw. des Wirkungsgrades des Kleinmagneten möglich.Due to the inventive design of the armature of the small magnet, the power requirement is z. B. only about 15% compared to an execution of the armature without permanent magnet arrangement. With appropriate design of the magnet-specific parts and materials, further increases in the responsiveness or the efficiency of the small magnet are possible.
Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und wird im folgenden näher erläutert. Es zeigen
- Fig. 1
- die Ansicht eines bistabilen Kleinmagneten im Schnitt in der Hubanfangsstellung,
- Fig. 2
- die Ansicht des Kleinmagneten gern. Fig. 1 in der Hubendstellung,
- Fig. 3
- die Ansicht eines Magnetankers,
- Fig. 4
- die Ansicht eines modifizierten Ankers,
- Fig. 5
- die Ansicht eines weiteren modifizierten Ankers,
- Fig. 6
- die Ansicht eines weiteren modifizierten Ankers, und
- Fig. 7
- die Ansicht eines modifizierten Kleinmagneten im Schnitt in der Hubanfangsstellung.
- Fig. 1
- the view of a bistable small magnet in section in the start of stroke position,
- Fig. 2
- like the view of the small magnet. 1 in the stroke end position,
- Fig. 3
- the view of a magnet armature,
- Fig. 4
- the view of a modified anchor,
- Fig. 5
- the view of another modified anchor,
- Fig. 6
- the view of another modified anchor, and
- Fig. 7
- the view of a modified small magnet in section in the stroke start position.
Der in den Fig. 1 und 2 dargestellte Kleinmagnet besteht im wesentlichen aus einem weichmagnetischen Magnetjoch 1, in das eine Erregerspule 2 mit einem in deren Spulenkörper 3 axial beweglichen Anker, der als Tauchanker ausgebildet ist, eingebaut ist. An einem Ende der Spule bzw. des Spulenkörpers ist ein Polstück 5 vorgesehen, gegen das der Anker bei entsprechend gerichteter Bestromung gezogen wird.
In den Anker 4 ist ein Permanentmagnet 6 eingefügt. Dabei ist dieser Permanentmagnet axial magnetisiert, wie durch die Kennzeichnung der Pole mit N und S verdeutlicht ist.The small magnet shown in FIGS. 1 and 2 consists essentially of a soft
A
In den Fig. 1 und 2 ist der Permanentmagnet als ringförmiger Magnet ausgebildet, durch dessen Mitte ein Teilstück 7 des weichmagnetischen Ankers verläuft. Dieses Teilstück wirkt als weichmagnetischer Parallelzweig.
Auf dem oberen Ende des Ankers 4 befindet sich eine Feder 8, die hier als Kegelstumpf-Druckfeder mit progressiver Kennlinie vorgesehen ist. Diese Feder ist in einer Zentrier- bzw. Halterungsausnehmung 9 im vorderen Ende des Spulenkörpers 3 gehalten bzw. abgestützt und wirkt gegen einen Ansatz 10 am Anker. Dieser Ansatz wird vorzugsweise durch Aufschnappen einer Sicherungsscheibe auf den Anker gebildet. Durch diesen Ansatz wird gleichzeitig in Verbindung mit dem entsprechend ausgebildeten Magnetjoch ein Anschlag bzw. eine Hubbegrenzung für den Anker in dessen Hubanfangsstellung realisiert.
Dabei wird der Anker - getrieben durch die Feder - so weit verschoben, bis der Anschlag am vorderen Ende des Magnetjochs anliegt.
Das untere Ende des Ankers 4 ist mit einem vorzugsweise durch Drehbearbeitung erzeugten Kegelstumpf 12 versehen, wobei der größere Durchmesser des Kegelstumpfes sich am äußeren Ende des Ankers befindet.
Das Polstück 5 weist eine zylindrische Ausnehmung 13 auf, in die dieser Kegelstumpf bei Anzug des Ankers eintaucht, wobei durch die Ausnehmung ein Schubhals 14 ausgebildet ist. Vorzugsweise ist der Schubhals auf seiner Außenseite konisch ausgeführt, wobei dann das dünnere Ende des Schubhalses sich an dessen Öffnung befindet.1 and 2, the permanent magnet is designed as an annular magnet, through the middle of which a
On the upper end of the
The armature - driven by the spring - is pushed until the stop is at the front end of the magnetic yoke.
The lower end of the
The
Der Kegelstumpf 12 des Ankers und die Länge des Schubhalses 14 sind aufeinander abgestimmt, wobei die Höhe des Kegelstumpfes in etwa der Länge des Schubhalses entspricht.
Durch die Gestaltung des Ankerendes als Kegelstumpf wird in Verbindung mit dem Schubhals ein besonders günstiger Kraft-Weg-Kennlinienverlauf erzielt, wobei je nach Dimensionierung von Kegelstumpf und Schubhals eine Kraftanhebung bei Hubanfang, im Mittelbereich des Hubes oder an einer anderen Stelle des Hubes bewirkt werden kann.The
By designing the anchor end as a truncated cone, a particularly favorable force-displacement characteristic curve is achieved in connection with the thrust neck, whereby depending on the dimensioning of the truncated cone and thrust neck, an increase in force can be brought about at the start of the stroke, in the central region of the stroke or at another point on the stroke .
Die Lage des Permanentmagneten innerhalb des Ankers ist so vorgesehen, daß bei der Hubanfangsstellung des Ankers (s. Fig. 1) ein Pol" in der Spule 2 eingetaucht ist und der andere Pol" sich außerhalb der wirksamen Kupferwicklung, d. h. vor der Stirnseite 15 der Spule befindet. Vorzugsweise ist vorgesehen, daß sich die Mitte des Permanentmagneten in etwa in der Ebene der Spulenstirnseite befindet.
Wie die Fig. 1 und 2 zeigen, ist der Anker 4 einerseits im Spulenkörper 3 und andererseits über einen Ankerabgriff bzw. Stößel 16 in einem nichtmagnetischen Lager 17 leichtgängig geführt.
Anstelle eines kleinen, separaten Lagers 17 kann ggf. auch ein kostengünstiger herstellbarer nichtmagnetischer Lagerdeckel 22, bei dem eine Durchgangsöffnung die Lagerstelle bildet, eingesetzt werden, wie in der Fig. 7 dargestellt.
Wird die Erregerspule 2 in einer solchen Richtung bestromt, daß das elektromagnetische Feld das Feld des Permanentmagneten gleichsinnig verstärkt, wird der Anker 4 in Richtung des Polstückes 5 gezogen. Neben dem elektromagnetischen und permanentmagnetischen Arbeitsfeld, welche sich im Luftspalt zwischen Polstück 5 und Anker 4 aufbaut, wird dabei zusätzlich eine gleichsinnige Kraftwirkung auf den Permanentmagneten 6 ausgeübt.
Vgl. Fig. 1: Nordpol N wird in die Spule hineingezogen, der in der Spule befindliche Südpol wird von dem am diesbezüglichen Spulensüdpol, der sich an der Stirnseite 15 der Spule aufbaut, abgestoßen und weiter in Richtung Spulenmitte getrieben. Es entsteht also ein Antriebsschub an beiden Polen des Permanentmagneten (Ankers) in gleicher Richtung.
Durch diese Kombination der vorstehend erläuterten Antriebsmechanismen wird eine hohe Ansprechempfindlichkeit erzielt und damit der Wirkungsgrad des Magnetsystems wesentlich erhöht.
Nach dem Bestromen der Erregerspule in der vorstehend geschilderten Richtung nimmt der Anker die in der Fig. 2 dargestellte permanentmagnetische Haftstellung ein. Diese wird nach Erreichen auch ohne weitere Bestromung der Erregerspule dauerhaft beibehalten.
Das Zurückschalten in die Hubanfangslage des Ankers wird durch Umpolen des elektromagnetischen Feldes ausgelöst. Hierdurch wird dann der magnetische Fluß in dem Polbereich des Polstückes 5 und dem Anker-Kegelstumpf 12 neutralisiert und verdrängt. Hierbei wird ein großer Anteil des permanentmagnetischen Flusses über den weichmagnetischen Parallelzweig 7 verdrängt. Die Umpolung des elektromagnetischen Feldes kann ggf. auch mittels einer zweiten Erregerspule erfolgen, sofern z. B. ein Umpolen des Spulenstroms nicht erfolgen soll.
Die vorstehend beschriebene Magnetanordnung stellt in Verbindung mit der Feder 8 einen bistabilen Aktuator dar, der sich mit kurzen, leistungsarmen Steuerimpulsen schnell in die jeweils andere Ankerendstellung umschalten läßt, in der er jeweils leistungslos verharrt.
Für die kostengünstige Herstellung großer Mengen dieser Magnete kann ggf. vorgesehen sein, daß das weichmagnetische Magnetjoch 1 durch ein nichtmagnetisches Joch, wie z.B. ein Kunststoffspritzteil, auch das Lager 17 mit umfassend, gebildet wird. Es hat sich gezeigt, daß die grundsätzliche Funktion des Magneten dennoch vorhanden ist.The position of the permanent magnet within the armature is provided in such a way that when the armature starts at the start of the stroke (see FIG. 1) Pol "is immersed in the
1 and 2 show, the
Instead of a small,
If the
See Fig. 1: North pole N is pulled into the coil, the south pole located in the coil is repelled by the corresponding south pole of the coil, which builds up on the
This combination of the drive mechanisms explained above achieves a high level of responsiveness and thus significantly increases the efficiency of the magnet system.
After energization of the excitation coil in the direction described above, the armature assumes the permanent magnetic holding position shown in FIG. 2. After reaching this, the excitation coil is permanently maintained even without further energization.
Switching back to the initial stroke position of the armature is triggered by reversing the polarity of the electromagnetic field. This then becomes the magnetic one Flow in the pole area of the
The magnet arrangement described above, in conjunction with the
For the cost-effective production of large quantities of these magnets, it may be provided that the soft
In den Fig. 3 bis 6 sind Anker 4 mit unterschiedlich eingefügten Permanentmagneten 6 dargestellt. Alle Anker weisen das gemeinsame Merkmal auf, daß sich ein axial magnetisierter Permanentmagnet innerhalb des Ankers befindet und daß ein weichmagnetischer Nebenschluß vorgesehen ist.3 to 6,
Bei dem Anker gern. Fig. 3 ist der Anker mit einer Ringnut versehen, in der ein ringförmiger Permanentmagnet 6 eingefügt ist. Dabei bildet das Mittel- bzw. Teilstück 7 des Ankers den Nebenschluß. Zur Herstellung des Ankers kann vorgesehen sein, daß entweder der Anker zweiteilig oder der ringförmige Permanentmagnet zweiteilig ausgebildet ist.
Der Permanentmagnet kann ggf. auch durch Umspritzung eines kunststoffgebundenen Permanentmagnetmaterials in den Anker eingebracht werdenHappy with the anchor. Fig. 3, the armature is provided with an annular groove in which an annular
The permanent magnet can optionally also be introduced into the armature by extrusion coating of a plastic-bonded permanent magnet material
Bei dem Anker gern. Fig. 4 ist der Anker mit einer Ausnehmung 18 versehen in die ein kreissegmentförmiger Permanentmagnet 6 eingefügt ist. Das neben dem Permanentmagneten vorhandene Anker-Teilstück 7 bildet dabei den weichmagnetischen Nebenschluß.Happy with the anchor. 4, the armature is provided with a
Bei dem Anker gern. Fig. 5 ist vorgesehen, daß dieser aus zwei Teilen zusammengefügt ist. Dabei ist das eine Teil mit einer Ausnehmung 19 versehen, in die der Permanentmagnet 6 eingesetzt ist. Die ringförmige Wand 20, die durch die Ausnehmung ausgebildet ist, bildet dabei dann den weichmagnetischen Nebenschluß.Happy with the anchor. Fig. 5 is provided that it is assembled from two parts. One part is provided with a recess 19 into which the
Schließlich zeigt Fig. 6 noch einen Anker 4, in den ein Permanentmagnet 6 mit dem gleichen Durchmesser wie der Anker selbst eingefügt ist. Der weichmagnetische Nebenschluß wird hierbei durch eine aufgeschobene, dünne Hülse 21 aus weichmagnetischem Material gebildet oder ggf. kann auch vorgesehen sein, daß die Anker- und Permanentmagnetoberfläche mit einem galvanisch aufgebrachten, weichmagnetischen Überzug versehen ist.Finally, FIG. 6 shows an
Claims (10)
dadurch gekennzeichnet,
characterized,
dadurch gekennzeichnet,
characterized,
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19608953A DE19608953A1 (en) | 1996-03-08 | 1996-03-08 | Bistable small magnet |
DE19608953 | 1996-03-08 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0794540A1 true EP0794540A1 (en) | 1997-09-10 |
EP0794540B1 EP0794540B1 (en) | 1999-04-28 |
Family
ID=7787586
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP97102643A Expired - Lifetime EP0794540B1 (en) | 1996-03-08 | 1997-02-19 | Small bistable magnet |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0794540B1 (en) |
AT (1) | ATE179546T1 (en) |
DE (2) | DE19608953A1 (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
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EP1022415A1 (en) * | 1999-01-19 | 2000-07-26 | Aug. Winkhaus GmbH & Co. KG | Electromagnetic actuated locking mechanism |
EP1022416A1 (en) * | 1999-01-19 | 2000-07-26 | Aug. Winkhaus GmbH & Co. KG | Electromagnetic actuated locking mechanism |
WO2000048207A2 (en) * | 1999-02-09 | 2000-08-17 | Nikolai Sergeevich Babich | Electromagnet and use thereof in closure devices |
DE102004047980B3 (en) * | 2004-10-01 | 2006-03-16 | Schliessanlagen Gmbh Pfaffenhain | Locking mechanism operated electromagnetically e.g. for key cylinder of mortise dead lock, has housing with cylinder core for key with electromagnets loaded in housing and tappet loaded and cooperates with linked spring |
WO2008096355A1 (en) * | 2007-02-08 | 2008-08-14 | Knock N'lock Ltd. | Solenoid-operated electromechanical lock |
FR2934923A1 (en) * | 2008-08-11 | 2010-02-12 | Schneider Electric Ind Sas | HYBRID ELECTROMAGNETIC ACTUATOR WITH FIXED COIL |
EP2428472A1 (en) * | 2010-09-14 | 2012-03-14 | Günther Zimmer | Separator with electrodynamic positioning member |
EP2452857A1 (en) * | 2010-11-16 | 2012-05-16 | JTEKT Corporation | Lock device and electric power steering system |
WO2012160262A1 (en) * | 2011-05-25 | 2012-11-29 | Ixtur Oy | Magnet, attaching device, attaching arrangement and method for attaching to an object |
CN102905845A (en) * | 2010-05-25 | 2013-01-30 | Ixtur有限公司 | Attaching device, attaching arrangement and method for attaching object to be worked to working base |
WO2014023451A1 (en) * | 2012-08-08 | 2014-02-13 | Eto Magnetic Gmbh | Bistable electromagnetic actuating apparatus, armature assembly and camshaft adjustment apparatus |
EP3185256A1 (en) * | 2015-12-14 | 2017-06-28 | SVM Schultz Verwaltungs-GmbH & Co. KG | Electromagnet |
WO2017114990A1 (en) * | 2015-12-28 | 2017-07-06 | Electrobolt Sistemas De Seguridad Sl | Remotely actuated electromagnetic locking device |
WO2018141817A1 (en) * | 2017-02-01 | 2018-08-09 | Rhefor Gbr | Electromagnetic stopper for an article conveyor system |
WO2018219529A1 (en) * | 2017-05-29 | 2018-12-06 | Robert Bosch Gmbh | Bistable solenoid valve for a hydraulic braking system and corresponding hydraulic braking system |
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DE20114466U1 (en) * | 2001-09-01 | 2002-01-03 | Eto Magnetic Kg | Electromagnetic actuator |
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EP0406957A2 (en) * | 1989-07-05 | 1991-01-09 | North American Philips Corporation | Hammer solenoid |
DE4327180A1 (en) * | 1993-08-13 | 1995-02-16 | Inopex Ges Fuer Produktentwick | Electromagnet |
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DE1489088A1 (en) * | 1964-10-30 | 1969-05-29 | List Dipl Ing Heinrich | Polarized electromagnetic propulsion system |
JPS5829754U (en) * | 1981-08-21 | 1983-02-26 | 日立金属株式会社 | Actuator for door lock |
-
1996
- 1996-03-08 DE DE19608953A patent/DE19608953A1/en not_active Withdrawn
-
1997
- 1997-02-19 AT AT97102643T patent/ATE179546T1/en not_active IP Right Cessation
- 1997-02-19 EP EP97102643A patent/EP0794540B1/en not_active Expired - Lifetime
- 1997-02-19 DE DE59700140T patent/DE59700140D1/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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DE3019418A1 (en) * | 1980-05-21 | 1981-11-26 | Hosiden Electronics Co | Double-coil self-holding solenoid - has fixed and moving armature with shaped interlocking ends and incorporates permanent magnet |
EP0406957A2 (en) * | 1989-07-05 | 1991-01-09 | North American Philips Corporation | Hammer solenoid |
DE4327180A1 (en) * | 1993-08-13 | 1995-02-16 | Inopex Ges Fuer Produktentwick | Electromagnet |
Cited By (31)
Publication number | Priority date | Publication date | Assignee | Title |
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EP1022416A1 (en) * | 1999-01-19 | 2000-07-26 | Aug. Winkhaus GmbH & Co. KG | Electromagnetic actuated locking mechanism |
EP1022415A1 (en) * | 1999-01-19 | 2000-07-26 | Aug. Winkhaus GmbH & Co. KG | Electromagnetic actuated locking mechanism |
WO2000048207A2 (en) * | 1999-02-09 | 2000-08-17 | Nikolai Sergeevich Babich | Electromagnet and use thereof in closure devices |
WO2000048207A3 (en) * | 1999-02-09 | 2001-10-04 | Nikolai Sergeevich Babich | Electromagnet and use thereof in closure devices |
DE102004047980B3 (en) * | 2004-10-01 | 2006-03-16 | Schliessanlagen Gmbh Pfaffenhain | Locking mechanism operated electromagnetically e.g. for key cylinder of mortise dead lock, has housing with cylinder core for key with electromagnets loaded in housing and tappet loaded and cooperates with linked spring |
US8375753B2 (en) | 2007-02-08 | 2013-02-19 | Knock N'lock Ltd. | Solenoid-operated electromechanical lock |
WO2008096355A1 (en) * | 2007-02-08 | 2008-08-14 | Knock N'lock Ltd. | Solenoid-operated electromechanical lock |
EP2570574A1 (en) * | 2007-02-08 | 2013-03-20 | Knock N'Lock Ltd. | Solenoid operated electromechanical lock |
WO2010018030A1 (en) * | 2008-08-11 | 2010-02-18 | Schneider Electric Industries Sas | Hybrid electromagnetic actuator with fixed coil |
FR2934923A1 (en) * | 2008-08-11 | 2010-02-12 | Schneider Electric Ind Sas | HYBRID ELECTROMAGNETIC ACTUATOR WITH FIXED COIL |
US9067290B2 (en) | 2010-05-25 | 2015-06-30 | Ixtur Oy | Attaching device, attaching arrangement and method for attaching an object to be worked to a working base |
CN102905845A (en) * | 2010-05-25 | 2013-01-30 | Ixtur有限公司 | Attaching device, attaching arrangement and method for attaching object to be worked to working base |
EP2428472A1 (en) * | 2010-09-14 | 2012-03-14 | Günther Zimmer | Separator with electrodynamic positioning member |
CN102529889B (en) * | 2010-11-16 | 2015-12-02 | 株式会社捷太格特 | Blocking device and electric power-assisted steering apparatus |
US8528688B2 (en) | 2010-11-16 | 2013-09-10 | Jtekt Corporation | Lock device and electric power steering system |
CN102529889A (en) * | 2010-11-16 | 2012-07-04 | 株式会社捷太格特 | Lock device and electric power steering system |
EP2452857A1 (en) * | 2010-11-16 | 2012-05-16 | JTEKT Corporation | Lock device and electric power steering system |
WO2012160262A1 (en) * | 2011-05-25 | 2012-11-29 | Ixtur Oy | Magnet, attaching device, attaching arrangement and method for attaching to an object |
WO2014023451A1 (en) * | 2012-08-08 | 2014-02-13 | Eto Magnetic Gmbh | Bistable electromagnetic actuating apparatus, armature assembly and camshaft adjustment apparatus |
CN104520947A (en) * | 2012-08-08 | 2015-04-15 | Eto电磁有限责任公司 | Bistable electromagnetic actuating apparatus, armature assembly and camshaft adjustment apparatus |
US9305693B2 (en) | 2012-08-08 | 2016-04-05 | Eto Magnetic Gmbh | Bistable electromagnetic actuating apparatus, armature assembly and camshaft adjustment apparatus |
EP3185256A1 (en) * | 2015-12-14 | 2017-06-28 | SVM Schultz Verwaltungs-GmbH & Co. KG | Electromagnet |
WO2017114990A1 (en) * | 2015-12-28 | 2017-07-06 | Electrobolt Sistemas De Seguridad Sl | Remotely actuated electromagnetic locking device |
WO2018141817A1 (en) * | 2017-02-01 | 2018-08-09 | Rhefor Gbr | Electromagnetic stopper for an article conveyor system |
CN110461740A (en) * | 2017-02-01 | 2019-11-15 | 雷福尔公司 | Electromagnetism retainer for freight conveyer system |
US10994946B2 (en) | 2017-02-01 | 2021-05-04 | Rhefor Gbr | Electromagnetic stopper for a cargo conveyor system |
CN110461740B (en) * | 2017-02-01 | 2022-01-18 | 雷福尔公司 | Electromagnetic stop for cargo conveyor system |
WO2018219529A1 (en) * | 2017-05-29 | 2018-12-06 | Robert Bosch Gmbh | Bistable solenoid valve for a hydraulic braking system and corresponding hydraulic braking system |
WO2018219530A1 (en) * | 2017-05-29 | 2018-12-06 | Robert Bosch Gmbh | Bistable solenoid valve for a hydraulic braking system and corresponding hydraulic braking system |
CN110709297A (en) * | 2017-05-29 | 2020-01-17 | 罗伯特·博世有限公司 | Bistable solenoid valve for a hydraulic brake system and corresponding hydraulic brake system |
CN110709297B (en) * | 2017-05-29 | 2021-12-21 | 罗伯特·博世有限公司 | Bistable solenoid valve for a hydraulic brake system and corresponding hydraulic brake system |
Also Published As
Publication number | Publication date |
---|---|
DE59700140D1 (en) | 1999-06-02 |
ATE179546T1 (en) | 1999-05-15 |
DE19608953A1 (en) | 1997-09-11 |
EP0794540B1 (en) | 1999-04-28 |
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