EP0732708A2 - Magnetic and/or magnetisable bobbin - Google Patents

Magnetic and/or magnetisable bobbin Download PDF

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Publication number
EP0732708A2
EP0732708A2 EP96103352A EP96103352A EP0732708A2 EP 0732708 A2 EP0732708 A2 EP 0732708A2 EP 96103352 A EP96103352 A EP 96103352A EP 96103352 A EP96103352 A EP 96103352A EP 0732708 A2 EP0732708 A2 EP 0732708A2
Authority
EP
European Patent Office
Prior art keywords
magnetic
winding
winding support
coil
core
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.)
Withdrawn
Application number
EP96103352A
Other languages
German (de)
French (fr)
Other versions
EP0732708A3 (en
Inventor
Mauricio Dipl.-Phys. Esguerra
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.)
TDK Electronics AG
Original Assignee
Siemens Matsushita Components GmbH and Co KG
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
Application filed by Siemens Matsushita Components GmbH and Co KG filed Critical Siemens Matsushita Components GmbH and Co KG
Publication of EP0732708A2 publication Critical patent/EP0732708A2/en
Publication of EP0732708A3 publication Critical patent/EP0732708A3/en
Withdrawn legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F17/00—Fixed inductances of the signal type 
    • H01F17/04—Fixed inductances of the signal type  with magnetic core
    • H01F17/045—Fixed inductances of the signal type  with magnetic core with core of cylindric geometry and coil wound along its longitudinal axis, i.e. rod or drum core
    • 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
    • H01F7/20—Electromagnets; Actuators including electromagnets without armatures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F3/00—Cores, Yokes, or armatures
    • H01F3/08—Cores, Yokes, or armatures made from powder

Definitions

  • the invention relates to a magnetic and / or magnetizable winding support for a coil, consisting of a bobbin and an open core made of a magnetic and / or magnetizable material.
  • the coil winding is wound on a plastic body, the coil body, and this is then pushed onto the core.
  • the coil thus produced is then cast in order to fix and protect the components. If a certain inductance value or a distribution of the magnetic external field is important for the application, this depends on an exact positioning of the winding with respect to the core. In the case of short coils, this geometrical influence even exceeds the influence which results from the fluctuations in the material permeability. The geometric fluctuations occur in practice due to mechanical tolerances in the manufacture of the core and bobbin, in the winding and in the assembly of the components.
  • the winding carrier advantageously consists at least partially of an FPC (ferrite-polymer composite).
  • the winding support can either consist entirely of one component, namely the FPC, or it can have at least two different components.
  • winding carrier is produced by means of the injection molding process.
  • FIG. 1 shows the sectional view of a winding carrier 1.
  • the winding support 1 is shaped so that it has two projections 2, 3 which enclose a chamber 4 in which the winding of the coil is applied.
  • the manufacture of the winding support 1 consists of a simultaneous manufacture of the core and the bobbin, preferably by means of the known injection molding process.
  • the winding support 1 is made of one component from, for example, FPC, but it can also consist of at least two consist of various components, all of which are either magnetic or magnetizable, of which at least one can also consist of an electrically insulating, non-magnetic material.
  • one of the projections 2 and 3 is made of non-magnetic material, since this projection belongs to the coil former. Actually, it should therefore be expected that the magnetic field distribution in the vicinity of a coil, which is made with the winding carrier according to the invention, is less favorable than with conventional, two-part winding carriers, since the formation of both projections with a magnetic or magnetizable material concentrates the magnetic field lines, and thus a weakening of the magnetic field, could be expected.
  • FIGS. 2 and 3 show the strength of the magnetic field Bz (T) in the case of a coil fitted around a metal cylinder.
  • FIG. 2 relates to a measuring radius r of 5 mm
  • FIG. 3 is based on a measuring radius r of 15 mm.
  • Curves A relate to a conventional spool with a winding applied to a spool and an open core
  • curves B relate to spools that are produced with a winding support according to the invention.
  • FIGS. 2 and 3 It can be seen from FIGS. 2 and 3 that, surprisingly, higher field strengths are achieved in the vicinity of the coil with a winding support according to the invention than with conventionally produced coils.
  • the magnetic field is to be used for energy transfers, e.g. in applications that are to be operated without a battery, such as immobilizers in motor vehicles.

Abstract

The magnetic and/or magnetisable coil carrier is provided for a spool comprising a spool body and an open core of magnetic or magnetisable material. The spool body and the core are formed in one piece. The coil carrier (1) is preferably, at least partly, made of a ferrite polymer composite. The carrier (1) may be made of one or more components. The carrier (1) may be made by injection moulding.

Description

Die Erfindung betrifft einen magnetischen und/oder magnetisierbaren Wickelträger für eine Spule, bestehend aus einem Spulenkörper und einem offenen Kern aus einem magnetischen und/oder magnetisierbaren Werkstoff.The invention relates to a magnetic and / or magnetizable winding support for a coil, consisting of a bobbin and an open core made of a magnetic and / or magnetizable material.

Bei Anwendungen mit offenen Kernen wird (wie auch bei geschlossenen Kernen) die Spulenwicklung auf einen Kunststoffkörper, den Spulenkörper, gewickelt und dieser dann auf den Kern geschoben. Anschließend wird die so hergestellte Spule zur Fixierung und Schutz der Komponenten vergossen. Kommt es bei der Anwendung auf die Einhaltung eines bestimmten Induktivitätswertes oder einer Verteilung des magnetischen Außenfeldes an, so ist dies von einer genauen Positionierung der Wicklung bezüglich des Kerns abhängig. Bei kurzen Spulen übersteigt dieser geometrische Einfluß sogar den Einfluß, der von den Schwankungen der Materialpermeabilität herrührt. Die geometrischen Schwankungen treten in der Praxis aufgrund von mechanischen Toleranzen in der Herstellung von Kern und Spulenkörper, bei der Bewicklung sowie bei der Montage der Komponenten auf.In applications with open cores (as with closed cores), the coil winding is wound on a plastic body, the coil body, and this is then pushed onto the core. The coil thus produced is then cast in order to fix and protect the components. If a certain inductance value or a distribution of the magnetic external field is important for the application, this depends on an exact positioning of the winding with respect to the core. In the case of short coils, this geometrical influence even exceeds the influence which results from the fluctuations in the material permeability. The geometric fluctuations occur in practice due to mechanical tolerances in the manufacture of the core and bobbin, in the winding and in the assembly of the components.

Aufgabe der vorliegenden Erfindung ist es daher, einen magnetischen und/oder magnetisierbaren Wickelträger anzugeben, bei dem die aufgezeigten Schwierigkeiten hinsichtlich der geometrischen Einflüsse weitestgehend beseitigt sind.It is therefore an object of the present invention to provide a magnetic and / or magnetizable winding carrier in which the difficulties identified with regard to the geometric influences have been largely eliminated.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß bei dem eingangs genannten Wickelträger Spulenkörper und Kern einstückig ausgebildet sind.This object is achieved in that the bobbin and core are integrally formed in the winding carrier mentioned above.

Damit wird der Vorteil erzielt, daß die Spulenwicklung in definierter Weise in Bezug auf den Kern positioniert werden kann.This has the advantage that the coil winding can be positioned in a defined manner with respect to the core.

Vorteilhafterweise besteht der Wickelträger zumindest teilweise aus einem FPC (Ferrit-Polymer-Composite). Hierbei kann der Wickelträger entweder ganz aus einer Komponente, nämlich dem FPC, bestehen oder er kann mindestens zwei unterschiedliche Komponenten aufweisen.The winding carrier advantageously consists at least partially of an FPC (ferrite-polymer composite). Here, the winding support can either consist entirely of one component, namely the FPC, or it can have at least two different components.

Vorteilhaft ist es, wenn der Wickelträger mittels des Spritzgußverfahrens hergestellt ist.It is advantageous if the winding carrier is produced by means of the injection molding process.

Der Gegenstand der Erfindung wird anhand der folgenden Ausführungsbeispiele näher erläutert.The object of the invention is explained in more detail with reference to the following exemplary embodiments.

In der dazu gehörenden Zeichnung zeigen

Figur 1
ein Schnittbild des Wickelträgers,
Figuren 2 und 3
den Verlauf der magnetischen Feldstärke von Spulen mit dem Wickelträger nach der Erfindung im Vergleich zu herkömmlichen Spulen, die einen geteilten Wickelträger besitzen.
Show in the accompanying drawing
Figure 1
a sectional view of the winding carrier,
Figures 2 and 3
the course of the magnetic field strength of coils with the winding carrier according to the invention compared to conventional coils which have a divided winding carrier.

In der Figur 1 ist das Schnittbild eines Wickelträgers 1 dargestellt. Der Wickelträger 1 ist dabei so geformt, daß er zwei Vorsprünge 2, 3 aufweist, die eine Kammer 4 einschließen, in der die Wicklung der Spule aufgebracht wird. Durch die Ausbildung des Wickelträgers 1 mit in den Kern integrierter Spule, kann die Wicklung direkt aufgebracht werden, so daß der Einfluß der mechanischen Toleranzen der separaten Komponenten auf die Konstanz der magnetischen Funktionen entfällt. Die Fertigung des Wickelträgers 1 besteht aus einer gleichzeitigen Fertigung von Kern- und Spulenkörper, vorzugsweise mittels des bekannten Spritzgußverfahrens.FIG. 1 shows the sectional view of a winding carrier 1. The winding support 1 is shaped so that it has two projections 2, 3 which enclose a chamber 4 in which the winding of the coil is applied. By designing the winding support 1 with a coil integrated in the core, the winding can be applied directly, so that the influence of the mechanical tolerances of the separate components on the constancy of the magnetic functions is eliminated. The manufacture of the winding support 1 consists of a simultaneous manufacture of the core and the bobbin, preferably by means of the known injection molding process.

Vorteilhafterweise ist der Wickelträger 1 einkomponentig aus z.B. FPC ausgebildet, er kann aber auch aus zumindest zwei verschiedenen Komponenten bestehen, die entweder alle magnetisch bzw. magnetisierbar sind, von denen mindestens eine aber auch aus einem elektrisch isolierendem, nicht magnetischem Material bestehen kann.Advantageously, the winding support 1 is made of one component from, for example, FPC, but it can also consist of at least two consist of various components, all of which are either magnetic or magnetizable, of which at least one can also consist of an electrically insulating, non-magnetic material.

Bei herkömmlichen, zweistückigen Wickelträgern ist einer der Vorsprünge 2 bzw. 3 aus nichtmagnetischem Material, da dieser Vorsprung zum Spulenkörper gehört. Eigentlich sollte deshalb erwartet werden, daß die magnetische Feldverteilung im Umkreis einer Spule, die mit dem Wickelträger nach der Erfindung hergestellt ist, ungünstiger ist, als bei herkömmlichen, zweistückigen Wickelträgern, da durch die Ausbildung beider Vorsprünge mit magnetischem bzw. magnetisierbarem Werkstoff eine Konzentrierung der magnetischen Feldlinien, und damit eine Abschwächung des Magnetfeldes, erwartet werden könnte.In conventional, two-piece winding carriers, one of the projections 2 and 3 is made of non-magnetic material, since this projection belongs to the coil former. Actually, it should therefore be expected that the magnetic field distribution in the vicinity of a coil, which is made with the winding carrier according to the invention, is less favorable than with conventional, two-part winding carriers, since the formation of both projections with a magnetic or magnetizable material concentrates the magnetic field lines, and thus a weakening of the magnetic field, could be expected.

Überraschenderweise hat sich aber herausgestellt, daß mit dem einstückigen Wickelträger nach der Erfindung die Feldstärkenverteilung in der Umgebung günstiger als bei herkömmlichen Wickelträgern ist.Surprisingly, however, it has been found that the field strength distribution in the area is more favorable than with conventional winding carriers with the one-piece winding carrier according to the invention.

In den Figuren 2 und 3 ist die Stärke des Magnetfeldes Bz(T) für den Fall einer um einen Metallzylinder angebrachten Spule dargestellt. Die Figur 2 bezieht sich dabei auf einen Meßradius r von 5 mm, während der Figur 3 ein Meßradius r von 15 mm zugrundeliegt. Die Kurven A beziehen sich dabei auf eine herkömmliche Spule mit auf einen Spulenkörper aufgebrachter Wicklung und offenem Kern, während sich die Kurven B auf Spulen beziehen, die mit einem Wickelträger nach der Erfindung hergestellt sind.FIGS. 2 and 3 show the strength of the magnetic field Bz (T) in the case of a coil fitted around a metal cylinder. FIG. 2 relates to a measuring radius r of 5 mm, while FIG. 3 is based on a measuring radius r of 15 mm. Curves A relate to a conventional spool with a winding applied to a spool and an open core, while curves B relate to spools that are produced with a winding support according to the invention.

Den Figuren 2 und 3 ist zu entnehmen, daß überraschenderweise in der Umgebung der Spule mit einem Wickelträger nach der Erfindung höhere Feldstärken erreicht werden als bei herkömmlich hergestellten Spulen.It can be seen from FIGS. 2 and 3 that, surprisingly, higher field strengths are achieved in the vicinity of the coil with a winding support according to the invention than with conventionally produced coils.

Dies ist insbesondere dann von Interesse, wenn mit Hilfe des Magnetfeldes Energieübertragungen vorgenommen werden sollen, z.B. bei Anwendungen, die ohne Batterie betrieben werden sollen, wie Wegfahrsperren in Kraftfahrzeugen.This is of particular interest if the magnetic field is to be used for energy transfers, e.g. in applications that are to be operated without a battery, such as immobilizers in motor vehicles.

Claims (5)

Magnetischer und/oder magnetisierbarer Wickelträger für eine Spule, bestehend aus einem Spulenkörper und einem offenen Kern aus einem magnetischen bzw. magnetisierbaren Werkstoff,
dadurch gekennzeichnet, daß Spulenkörper und Kern einstückig ausgebildet sind.Magnetic and / or magnetizable winding support for a coil, consisting of a coil body and an open core made of a magnetic or magnetizable material,
characterized in that the bobbin and core are integrally formed. Magnetischer Wickelträger nach Anspruch 1,
dadurch gekennzeichnet, daß der Wickelträger (1) zumindest teilweise aus einem FPC (Ferrit-Polymer-Composite) besteht.Magnetic winding support according to claim 1,
characterized in that the winding support (1) consists at least partially of an FPC (ferrite-polymer composite). Magnetischer Wickelträger nach Anspruch 2,
dadurch gekennzeichnet, daß der Wickelträger (1) aus einer Komponente besteht.Magnetic winding support according to claim 2,
characterized in that the winding support (1) consists of one component. Magnetischer Wickelträger nach Anspruch 2,
dadurch gekennzeichnet, daß der Wickelträger (1) aus zumindest zwei unterschiedlichen Komponenten besteht.Magnetic winding support according to claim 2,
characterized in that the winding support (1) consists of at least two different components. Magnetischer Wickelträger nach einem der Ansprüche 1 bis 4,
dadurch gekennzeichnet, daß er mittels Spritzguß hergestellt ist.Magnetic winding support according to one of claims 1 to 4,
characterized in that it is made by injection molding.
EP96103352A 1995-03-15 1996-03-04 Magnetic and/or magnetisable bobbin Withdrawn EP0732708A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19509264A DE19509264A1 (en) 1995-03-15 1995-03-15 Magnetic and / or magnetizable winding carrier
DE19509264 1995-03-15

Publications (2)

Publication Number Publication Date
EP0732708A2 true EP0732708A2 (en) 1996-09-18
EP0732708A3 EP0732708A3 (en) 1996-09-25

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EP96103352A Withdrawn EP0732708A3 (en) 1995-03-15 1996-03-04 Magnetic and/or magnetisable bobbin

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EP (1) EP0732708A3 (en)
JP (1) JPH08264315A (en)
KR (1) KR960035676A (en)
AU (1) AU4810096A (en)
CA (1) CA2171700A1 (en)
DE (1) DE19509264A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10139446A1 (en) * 2001-08-10 2003-02-20 Conti Temic Microelectronic Magnetisable or magnetic coil body for magnetic coils for valve control has unmagnetized intermediate body part arranged axially between magnetic or magnetisable parts of coil body
DE102010044812A1 (en) * 2010-09-09 2012-03-15 Eto Magnetic Gmbh Electromagnetic positioning device has bobbin which is comprised of magnetizable material such that permanent magnetization is obtained according to energization of winding, with predetermined magnetizing coil current of bobbin

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102020207000B4 (en) 2019-06-19 2023-02-23 Universität Stuttgart, Körperschaft Des Öffentlichen Rechts Electrically excited machine and arrangement for an electrically excited machine

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0112577A1 (en) * 1982-12-27 1984-07-04 Kabushiki Kaisha Toshiba Magnetic core and method of producing the same
JPH0437104A (en) * 1990-06-01 1992-02-07 Tokin Corp Ferrite core for rotary transformer and manufacture thereof
JPH04297007A (en) * 1991-03-26 1992-10-21 Sony Corp Coil bobbin and coil base
US5184105A (en) * 1990-05-11 1993-02-02 Toko Kabushiki Kaisha Bobbin for multiple-connected inductor
EP0642142A2 (en) * 1993-09-01 1995-03-08 Philips Electronique Grand Public Self-inductance coil

Family Cites Families (3)

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Publication number Priority date Publication date Assignee Title
US1762544A (en) * 1928-07-16 1930-06-10 Warner Electric Brake Corp Magnet construction
US2648124A (en) * 1947-08-09 1953-08-11 Duyck Georges Method of manufacturing electromagnets
CH621428A5 (en) * 1977-12-15 1981-01-30 Sulzer Ag

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0112577A1 (en) * 1982-12-27 1984-07-04 Kabushiki Kaisha Toshiba Magnetic core and method of producing the same
US5184105A (en) * 1990-05-11 1993-02-02 Toko Kabushiki Kaisha Bobbin for multiple-connected inductor
JPH0437104A (en) * 1990-06-01 1992-02-07 Tokin Corp Ferrite core for rotary transformer and manufacture thereof
JPH04297007A (en) * 1991-03-26 1992-10-21 Sony Corp Coil bobbin and coil base
EP0642142A2 (en) * 1993-09-01 1995-03-08 Philips Electronique Grand Public Self-inductance coil

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 016, no. 221 (E-1205), 22.Mai 1992 & JP-A-04 037104 (TOKIN CORP), 7.Februar 1992, *
PATENT ABSTRACTS OF JAPAN vol. 017, no. 115 (E-1330), 10.März 1993 & JP-A-04 297007 (SONY CORP), 21.Oktober 1992, *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10139446A1 (en) * 2001-08-10 2003-02-20 Conti Temic Microelectronic Magnetisable or magnetic coil body for magnetic coils for valve control has unmagnetized intermediate body part arranged axially between magnetic or magnetisable parts of coil body
DE10139446B4 (en) * 2001-08-10 2021-05-20 Conti Temic Microelectronic Gmbh Bobbin
DE102010044812A1 (en) * 2010-09-09 2012-03-15 Eto Magnetic Gmbh Electromagnetic positioning device has bobbin which is comprised of magnetizable material such that permanent magnetization is obtained according to energization of winding, with predetermined magnetizing coil current of bobbin
DE102010044812B4 (en) * 2010-09-09 2012-11-29 Eto Magnetic Gmbh A method of manufacturing an electromagnetic actuator and an electromagnetic actuator manufactured thereby

Also Published As

Publication number Publication date
EP0732708A3 (en) 1996-09-25
KR960035676A (en) 1996-10-24
JPH08264315A (en) 1996-10-11
AU4810096A (en) 1996-09-26
CA2171700A1 (en) 1996-09-16
DE19509264A1 (en) 1996-09-19

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