EP0986073B1 - Noyau de transformateur du type a separation - Google Patents

Noyau de transformateur du type a separation Download PDF

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Publication number
EP0986073B1
EP0986073B1 EP99912044A EP99912044A EP0986073B1 EP 0986073 B1 EP0986073 B1 EP 0986073B1 EP 99912044 A EP99912044 A EP 99912044A EP 99912044 A EP99912044 A EP 99912044A EP 0986073 B1 EP0986073 B1 EP 0986073B1
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EP
European Patent Office
Prior art keywords
soft magnetic
core
magnetic material
isolation transformer
ferrite
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Expired - Lifetime
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EP99912044A
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German (de)
English (en)
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EP0986073A1 (fr
EP0986073A4 (fr
Inventor
Dongzhi The Furukawa Electric Co. Ltd JIN
Fumihiko The Furukawa Electric Co. Ltd ABE
Hajime The Furukawa Electric Co. Ltd MOCHIZUKI
Hideharu The Furukawa Electric Co. Ltd YONEHARA
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Furukawa Electric Co Ltd
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Furukawa Electric Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/18—Rotary transformers
    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/14—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 soft-magnetic materials metals or alloys
    • H01F1/20—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 soft-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H01F1/22—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 soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together
    • H01F1/24—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 soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated
    • H01F1/26—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 soft-magnetic materials metals or alloys in the form of particles, e.g. powder pressed, sintered, or bound together the particles being insulated by macromolecular organic substances
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/24—Magnetic cores
    • H01F27/255—Magnetic cores made from particles
    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/14—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 soft-magnetic materials metals or alloys
    • H01F1/147—Alloys characterised by their composition
    • H01F1/14766—Fe-Si based alloys
    • H01F1/14791—Fe-Si-Al based alloys, e.g. Sendust
    • 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
    • H01F1/12—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 soft-magnetic materials
    • H01F1/34—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 soft-magnetic materials non-metallic substances, e.g. ferrites
    • H01F1/36—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 soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles
    • H01F1/37—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 soft-magnetic materials non-metallic substances, e.g. ferrites 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
    • H01F17/00—Fixed inductances of the signal type 
    • H01F17/04—Fixed inductances of the signal type  with magnetic core
    • H01F2017/048—Fixed inductances of the signal type  with magnetic core with encapsulating core, e.g. made of resin and magnetic powder
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F19/00—Fixed transformers or mutual inductances of the signal type
    • H01F19/04—Transformers or mutual inductances suitable for handling frequencies considerably beyond the audio range
    • H01F19/08—Transformers having magnetic bias, e.g. for handling pulses
    • H01F2019/085—Transformer for galvanic isolation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/14—Inductive couplings

Definitions

  • the present invention relates to an isolation transformer core, and more specifically to an isolation transformer applicable to an automobile component.
  • An isolation transformer is a transformer in which cores having coils are arranged to face each other to transmit electric power or an electric signal between each other through electromagnetic coupling of the opposite coils in a contactless manner.
  • a rotary transformer in which a primary core is fixed and a secondary core is rotatably arranged is an isolation transformer of this type, and a rotary transformer for a rotary head of a video tape recorder is generally known.
  • the rotary transformer in order to make a coupling coefficient of coils in cores large, cores having a high relative permeability are used and a gap between the cores is restricted to several ⁇ m.
  • the coupling coefficient of the coils when the coupling coefficient of the coils is very large, self-inductance and mutual inductance of the two opposite coils cancel each other, so that input-output impedance of the transformer is small. Therefore, in the rotary transformer, impedance matching between the coils and a load can be easily attained.
  • sintered ferrite cores are generally used as cores of the rotary transformer.
  • the sintered ferrite core is favorable as a core of a high frequency transformer in that it has a very high relative permeability and produces only a very small eddy-current loss.
  • the size of a gap between the cores has a direct influence on manufacturing cost.
  • a rotary transformer having a large coupling coefficient of coils in order to provide a gap between cores of several ⁇ m, high manufacturing precision and high assembling precision of components are required, which cause high manufacturing cost.
  • strict restriction is imposed on manufacturing cost and very strong vibration is produced during driving. Therefore, the rotary transformer for an automobile needs to have a gap of 0.5 mm or larger between the opposite cores.
  • the sintered ferrite core has favorable properties as mentioned above, but has a drawback peculiar to sintered oxide: fragility.
  • sintered ferrite cores are to be used as cores of a connector for an automobile, for example, cores of a connector for an air bag, various consideration is needed, for example, about how to prevent vibration, how to fix the cores and the like. Also in view of manufacturing cost, the sintered ferrite core is difficult to apply to an automobile component.
  • the present invention has been made in view of the above problems.
  • the object thereof is to provide an isolation transformer core which is less fragile and easy to manufacture.
  • U.S. Patent no. 5,160,447 discloses a compressed powder magnetic core having stable magnetic characteristics and the method for manufacturing the same. In order to achieve this object, the sum of the proportions of the void and the resin in the compressed powder magnetic core is limited to the range of 7% to 50% by volume.
  • PATENT ABSTRACTS OF JAPAN, vol. 012, no. 035 (E-579), 2 February 1988 (1988-02-02 ) & JP 62 188303 A (SHIGEO FUKUDA), 17 August 1987 discloses a process of manufacturing a magnetic core or a rotary transformer for use in a videotape recorder.
  • E.P. no. 0 587 142 A2 discloses a rotary transformer having a gap of 50 or 70 ⁇ m that can be used as a signal transmitting element for a rotary head cylinder in a video tape recorder, a digital audiotape recorder and the like.
  • an isolation transformer used as a connector for an air bag needs to be able to make large current flow to an air bag inflating unit under a low voltage of 12V (battery for an automobile) to transmit large power at a high speed.
  • impedance matching between a load and coils is very important.
  • the inventors have researched on the effective relative permeability between coils of an isolation transformer (for example, using generally used sintered ferrite cores having a relative permeability of about 3000 to 10000).
  • the effective relative permeability in the magnetic circuit varies to a large extent, depending on the size of the gap. This means that the coupling state of the coils varies even when the gap between the cores varies only a little due to vibration of the automobile.
  • the effective relative permeability in the magnetic circuit almost exclusively depends on the size of the gap between the cores. Therefore, however high the relative permeability of the core members may be, the effective relative permeability in the magnetic circuit is almost determined by the size of the gap between the cores.
  • the effective relative permeability in the magnetic circuit formed between the coils is determined by the relative permeability of the core members and the size of the gap between the cores, and that the size of the gap between the cores is a factor having a particularly large influence on the effective relative permeability in the magnetic circuit.
  • an isolation transformer using cores of magnetic material of a low relative permeability for example, mixed magnetic material
  • having a larger gap between the cores shows an effective relative permeability in the magnetic circuit between the coils slightly lower than that of an isolation transformer using conventional sintered ferrite cores, but that it is suited to, transmit large power in a moment and has advantages of improved vibration resistance and lowered manufacturing cost (suited for mass production).
  • the present invention has been made to obtain an isolation transformer core suitable for a connector for an air bag which is installed in an automobile and needs to be able to transmit large power in a moment.
  • the isolation transformer core of the present invention comprises a coil and a core member according to claim 1.
  • FIG. 1 is a cross-sectional view of an isolation transformer core used in the present invention
  • FIG. 2 is a graph showing the relation between the soft magnetic ferrite content of mixed soft magnetic material and the melt flow rate of the mixed soft magnetic material
  • FIG. 3 is a graph showing the relation between the soft magnetic ferrite content of mixed soft magnetic material and the relative permeability of a core member formed thereof
  • FIG. 4 shows volume resistivity characteristic curves indicating the relation between the soft magnetic ferrite content (volume %) of mixed soft magnetic material and the volume resistivity ( ⁇ cm) of the mixed soft magnetic material
  • FIG. 5 shows relative permeability characteristic curves indicating the relation between the soft magnetic material (soft magnetic ferrite, Sendust, permalloy) content (volume %) and the relative permeability.
  • an isolation transformer core 1 used in the present invention comprises a core member 2 and a coil 3.
  • the core member 2 is made of a mixed soft magnetic material which is a mixture of an insulating material having an electrical insulating property and a soft magnetic material, and formed into a desired core shape.
  • the soft magnetic material content of the mixed soft magnetic material is lower than 10 volume %, the relative permeability of the core member formed thereof is lower than 2, so that it is difficult to attain the required transmission efficiency of an isolation transformer.
  • the soft magnetic material content is higher than 70 volume %, the relative permeability of the core member formed thereof is high (it may be higher than 20, depending on the kind and grain diameter of soft magnetic material). This is favorable to raise the transmission efficiency of an isolation transformer, but the core itself is fragile.
  • synthetic resin (described later) is used as the insulating material, flowability lowers, which makes injection molding difficult. Therefore, the soft magnetic material content of the mixed soft magnetic material is chosen in the range of 10 to 70 volume %.
  • synthetic resin is favorable to be used as the insulating material.
  • a thermoplastic resin such as nylon 6, nylon 66, nylon 11, nylon 12, polypropylene, polyphenylene sulfide or polyolefine, a thermoplastic rubber such as urethane, polyester or olefine, a thermosetting resin such as silicone rubber, epoxy resin, phenolic resin or diallyl phthalete, or two-liquid mixing adhesive can be used.
  • injection molding or the like can be applied to the mixed soft magnetic material. Therefore, a core member of a desired shape can be formed easily. Further, since the synthetic resin has flexibility, shock resistance of the formed core member is improved, and therefore the vibration resistance of the isolation transformer core itself is improved.
  • ceramic is favorable to be used as the insulating material.
  • Zirconia ceramic or silicon nitride ceramic which have high strength and high toughness can be used.
  • zirconia ceramic partial stabilized zirconia ceramic is in particular favorable.
  • powdered ceramic and powdered soft magnetic material are mixed to produce a mixed soft magnetic material.
  • the mixed soft magnetic material is formed into a desired shape and subjected to press sintering or HIP (hot isostatic pressing) to produce a desired isolation transformer core.
  • the isolation transformer core produced this way has better heat resistance and wear resistance due to the ceramic.
  • nylon is favorable in that it is inexpensive, fuses well with the soft magnetic material, and exhibits good flowability in injection molding.
  • soft magnetic material for example, soft magnetic ferrite, Sendust, permalloy, high-permeability amorphous material or the like can be used.
  • the soft magnetic ferrite for example, spinel ferrite represented by a general expression MO ⁇ Fe 2 O 3 (where M is at least one element chosen from Zn, Mn, Ni, Cu and Fe), or compound ferrite made of several kinds of the above spinel ferrites can be used.
  • Mn-Zn ferrite, Ni-Zn ferrite and Ni-Zn-Cu ferrite are in particular favorable.
  • the soft magnetic ferrite is used in a powdered state, and powdered soft magnetic ferrite whose maximum grain diameter is 100 ⁇ m or smaller is favorable. Powdered soft magnetic ferrite having an average grain diameter of 3.8 ⁇ m is more favorable
  • Fe-Si-Al alloy containing about 6 to 11 weight % of Si and about 4 to 6 weight % of Al can be used. 9.62 weight % Si-5.38 weight % Al-bal.Fe alloy is in particular favorable.
  • the Sendust is used in a powdered state. Powdered Sendust having an average grain diameter of 10 ⁇ m or smaller is favorable.
  • Fe-Ni alloy containing 35 to 80 weight % of Ni can be used as the permalloy. 78 weight % Ni permalloy, 48 weight % Ni permalloy, and supermalloy (79 weight % Ni-5 weight % Mo-0.3 weight % Mn-bal.Fe) are favorable.
  • the permalloy is used in a powdered state. Powdered permalloy whose maximum grain diameter is 100 ⁇ m or smaller is favorable.
  • high-permeability amorphous material Fe amorphous material or Co amorphous material can be used.
  • the high-permeability amorphous material is also used in a powdered state having an average grain diameter of 1 to 500 ⁇ m.
  • an insulating material and a soft magnetic material are mixed and fused to produce a mixed soft magnetic material 2.
  • the mixed soft magnetic material 2 exhibits good flowability when it is heated to fuse. Therefore, it can be easily formed by injection molding into a desired shape, for example, into a disc-shaped core member 2 having a though-hole 2a at the center and a coil groove 2b for receiving a coil 3 in the disc face, as shown in FIG. 1 .
  • a coil 3 having a predetermined number of turns is placed in the coil groove 2b of the formed core member 2 to form an isolation transformer core 1.
  • an isolation transformer core may be molded from the mixed soft magnetic material together with the coil 3 having a predetermined number of turns.
  • the isolation transformer cores each having a coil placed therein are arranged to face each other to form an isolation transformer.
  • the isolation transformer is used, for example, as a connector for an air bag.
  • a primary transformer core is set on a fixed portion (a column side) and a secondary transformer core is set on a rotary portion (steering portion).
  • the primary and secondary transformer cores are arranged to face each other with a gap of 1mm ⁇ 0.5mm therebetween.
  • a primary-side coil is connected with a control unit for controlling an air bag inflating unit, and a secondary-side coil is connected with the air bag inflating unit.
  • the core members of the present invention have a relatively low relative permeability (for example, the relative permeability of a core member made of a mixed soft magnetic material comprising soft magnetic ferrite (MnFe 2 O 4 -ZnFe 2 O 4 ) and nylon 6 is about 3 to 12). Therefore, the inductance of the coils is small, and therefore impedance matching between the coils and a load, that is, the inflating unit can be easily attained.
  • the isolation transformer using the isolation transformer cores comprising the core members described above is suited to transmit large power in a moment.
  • Mn-Zn soft magnetic ferrite (MnFe 2 O 4 -ZnFe 2 O 4 ) powder and Ni-Zn soft magnetic ferrite (NiO-ZnO-Fe 2 O 3 ) powder whose maximum grain diameter was 50 ⁇ m were prepared.
  • insulating materials having an insulating property nylon pellets (nylon 6) and polypropylene pellets as used in 10 ordinary injection molding and the like were prepared. Using these materials, several kinds of mixed powders having different soft magnetic ferrite powder contents were prepared. Each mixed powder was then fused, so that several kinds of mixed soft magnetic materials having different soft magnetic ferrite contents were prepared.
  • the melt flow rate of mixed soft magnetic materials containing nylon 6 as an insulating material was measured by a melt index test in accordance with JIS K 7210. Measurement was performed under the condition that measurement temperature was 270°C and a load was 98.0N (10.0 kg ⁇ f). When the soft magnetic ferrite content was 5 volume % or lower, the soft magnetic ferrite content had little influence on the melt flow rate. When the soft magnetic ferrite content was 70 volume % or higher, mixing to produce a mixed soft magnetic material was difficult. Therefore, the melt flow rate of mixed soft magnetic materials having the soft magnetic ferrite content of 5 to 65 volume % was measured by the melt index test. The results are shown in FIG. 2 .
  • core members were formed as follows:
  • the relative permeability of formed core members was measured in accordance with JIS C2561. The results are shown as the relation between the soft magnetic ferrite content (volume %) and the relative permeability of a core member in FIG. 3 , where black circles represent core members using nylon 6 as an insulating material and white circles represent core members using polypropylene as an insulating material.
  • volume resistivity of mixed soft magnetic materials was measured in accordance with JIS H 0505. The results are shown as the relation between the soft magnetic ferrite content (volume %) and the volume resistivity ( ⁇ cm) of mixed soft magnetic materials in FIG. 4 , where black circles represent mixed soft magnetic materials using Mn-Zn ferrite as a soft magnetic ferrite and white circles represent mixed soft magnetic materials using Ni-Zn ferrite as a soft magnetic ferrite.
  • FIG. 5 shows the relation between the soft magnetic ferrite content (volume %) and the relative permeability, the Sendust content (volume %) and the relative permeability and the permalloy content (volume %) and the relative permeability. This was obtained by calculation based on the measurement results of the soft magnetic ferrite content (volume %) and the relative permeability shown in FIG. 3 , using general data on Sendust and permalloy. Soft magnetic ferrite, Sendust and permalloy were used as soft magnetic materials.
  • the soft magnetic ferrite content is higher than 70 volume %, mixing is difficult, and injection molding is difficult due to low flowability. Further, due to an increase of ferrite component having high hardness, a mold for injection molding wears quickly, the mechanical strength of a formed isolation transformer core is much lower, and a core is more difficult to form. Thus, the mixed soft magnetic material having the soft magnetic ferrite content higher than 70 volume % is unsuitable for a transformer core.
  • the soft magnetic ferrite content is in the range of 60 to 70 volume %, the relative permeability of a formed core member is high, but the flowability of a mixed soft magnetic material is relatively low.
  • the mixed soft magnetic material having the soft magnetic ferrite content of this range is suitable for a core which is used in an isolation transformer requiring a relatively high transmission efficiency and does not have a very complicated shape.
  • the soft magnetic ferrite content is in the range of 10 to 60 volume %, the relative permeability of a formed core member is relatively low, but the flowability of a mixed soft magnetic material is high.
  • the mixed soft magnetic material having the soft magnetic ferrite content of this range is suitable for a core which is used in an isolation transformer not requiring a high transmission efficiency and has such a complicated shape that it can be formed only of material having a high flowability.
  • a mixed soft magnetic material containing Ni-Zn ferrite has a high volume resistivity, though it is expensive. It is desirable to use a mixed soft magnetic material containing Ni-Zn ferrite when a mixed soft magnetic material containing Mn-Zn ferrite does not satisfy a required volume resistivity.
  • mixed soft magnetic material having the Mn-Zn soft magnetic ferrite content of 50 ⁇ 3 volume % is particularly favorable.
  • This mixed soft magnetic material has a good flowability and a relatively high melt flow rate, and injection molding thereof is easy.
  • the relative permeability of a core member formed thereof is about 10.
  • an isolation transformer core formed of this mixed soft magnetic material is suitable for a connector for an air bag which has two cores arranged to face each other with a gap of 1 mm therebeteween and needs to be able to surely transmit large power in a moment even if a gap varies in the range of ⁇ 0.5 mm.
  • a core member is made of a mixed soft magnetic material comprising an insulating material having an electrical insulating property and a soft magnetic material.
  • the isolation transformer core has an improved vibration resistance and a lowered fragility.
  • the relative permeability of a coil is relatively low. Therefore, the isolation transformer cores are suited to be arranged to face each other with a gap of about 1 mm therebeteween and transmit large power in a moment.
  • the isolation transformer core of the present invention has the relative permeability required for transmitting large power in a moment, and at the same time a mechanical strength higher than that of a core made of sintered ferrite alone.
  • the isolation transformer core of the present invention uses, as a soft magnetic material, soft magnetic ferrite or Sendust.
  • the isolation transformer core using soft magnetic ferrite is suitable for a high-frequency transformer, because it has only a small eddy-current loss.
  • the isolation transformer core using Sendust is advantageous in that it can be of a small size because it has a high saturation magnetic flux density (twice as high as that of ferrite).
  • the isolation transformer core uses, as an insulating material, any of thermoplastic resin (present invention), thermoplastic rubber, silicone rubber, thermosetting resin and adhesive which all have flexibility and good formability. Therefore, the isolation transformer core has large shock resistance, and is easy to form even when it has a complicated shape. Thus, the vibration resistance of the isolation transformer core is much improved and manufacturing cost is lowered.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Dispersion Chemistry (AREA)
  • Soft Magnetic Materials (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Insulating Of Coils (AREA)

Abstract

L'invention concerne un noyau de transformateur (1) du type à séparation qui comprend une bobine (3) et un matériau de noyau (2), ledit matériau de noyau (2) comportant un matériau isolant manifestant des propriétés d'isolation électrique ainsi qu'un matériau magnétique souple mixte, la part du matériau magnétique souple étant égale ou supérieure à 10 % en volume et inférieure ou égale à 70 % en volume.

Claims (4)

  1. Transformateur d'isolement, comprenant :
    des noyaux de transformateur (1), placés en regard les uns des autres avec un intervalle entre eux, pour former un circuit magnétique et comprenant chacun une bobine (3) et un élément de noyau (2) logeant la bobine (3), les éléments de noyau (2) contiennent chacun une poudre de matériau magnétique doux, le matériau isolant de l'électricité étant constitué de résine thermoplastique, caractérisé en ce que l'intervalle est supérieur ou égal à 0,5 mm, et
    les éléments de noyau (2) contiennent chacun de 10 à 70 % en volume de ladite poudre de matériau magnétique doux et ont chacun une perméable relative dans la fourchette comprise entre 2 et 20.
  2. Transformateur d'isolement selon la revendication 1, caractérisé en ce que la poudre de matériau magnétique doux est une ferrite magnétique douce ou du Sendust.
  3. Transformateur d'isolement selon la revendication 1, caractérisé en ce que les éléments de noyau (2) contiennent chacun de 10 à 60 % en volume de la poudre de matériau magnétique doux.
  4. Transformateur d'isolement selon la revendication 3, caractérisé en ce que les éléments de noyau (2) ont chacun une perméabilité relative dans la fourchette de 3 à 12.
EP99912044A 1998-03-27 1999-03-26 Noyau de transformateur du type a separation Expired - Lifetime EP0986073B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP8165198 1998-03-27
JP8165198 1998-03-27
PCT/JP1999/001567 WO1999050858A1 (fr) 1998-03-27 1999-03-26 Noyau de transformateur du type a separation

Publications (3)

Publication Number Publication Date
EP0986073A1 EP0986073A1 (fr) 2000-03-15
EP0986073A4 EP0986073A4 (fr) 2006-09-20
EP0986073B1 true EP0986073B1 (fr) 2011-02-09

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EP99912044A Expired - Lifetime EP0986073B1 (fr) 1998-03-27 1999-03-26 Noyau de transformateur du type a separation

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EP (1) EP0986073B1 (fr)
JP (1) JP4278719B2 (fr)
KR (1) KR100533494B1 (fr)
CA (1) CA2291104C (fr)
DE (1) DE69943179D1 (fr)
WO (1) WO1999050858A1 (fr)

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JP4593053B2 (ja) * 2000-03-08 2010-12-08 古河電気工業株式会社 分離型トランス用の異常診断方法及びその装置
FR2976152B1 (fr) * 2011-05-31 2013-06-28 Renault Sa Ecran de blindage magnetique pour charge sans contact d'une batterie d'un vehicule automobile
US20160276079A1 (en) * 2013-11-01 2016-09-22 Toda Kogyo Corp. Soft magnetic ferrite resin composition, soft magnetic ferrite resin composition molded product, and power transmission device for non-contact power feeder system
KR102166881B1 (ko) * 2014-04-03 2020-10-16 엘지이노텍 주식회사 무선 전력 송신 장치
WO2015173196A1 (fr) * 2014-05-14 2015-11-19 Dsm Ip Assets B.V. Composition de matériau magnétique doux et composant constitué du matériau
KR102283168B1 (ko) * 2014-11-17 2021-07-29 엘지이노텍 주식회사 연자성 합금, 이를 포함하는 무선 전력 송신 장치 및 무선 전력 수신 장치

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EP0986073A1 (fr) 2000-03-15
DE69943179D1 (de) 2011-03-24
JP4278719B2 (ja) 2009-06-17
KR20010012948A (ko) 2001-02-26
WO1999050858A1 (fr) 1999-10-07
CA2291104A1 (fr) 1999-10-07
CA2291104C (fr) 2010-11-30
KR100533494B1 (ko) 2005-12-06
EP0986073A4 (fr) 2006-09-20
WO1999050858A8 (fr) 1999-12-02

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