US3775841A - Method of adjusting the dimensions of sintered ferromagnetic cores - Google Patents

Method of adjusting the dimensions of sintered ferromagnetic cores Download PDF

Info

Publication number
US3775841A
US3775841A US00184696A US3775841DA US3775841A US 3775841 A US3775841 A US 3775841A US 00184696 A US00184696 A US 00184696A US 3775841D A US3775841D A US 3775841DA US 3775841 A US3775841 A US 3775841A
Authority
US
United States
Prior art keywords
dimensions
core
coil
sintered
adjusting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00184696A
Other languages
English (en)
Inventor
F Lathouwers
Groot J De
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.)
US Philips Corp
Original Assignee
US Philips Corp
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 US Philips Corp filed Critical US Philips Corp
Application granted granted Critical
Publication of US3775841A publication Critical patent/US3775841A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/0206—Manufacturing of magnetic cores by mechanical means
    • H01F41/0246—Manufacturing of magnetic circuits by moulding or by pressing powder
    • 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
    • H01F37/00—Fixed inductances not covered by group H01F17/00
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/0206—Manufacturing of magnetic cores by mechanical means
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/236—Manufacture of magnetic deflecting devices for cathode-ray tubes
    • 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
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/04—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing coils
    • H01F41/06—Coil winding
    • H01F41/071—Winding coils of special form
    • H01F2041/0711—Winding saddle or deflection coils
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49071—Electromagnet, transformer or inductor by winding or coiling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49075—Electromagnet, transformer or inductor including permanent magnet or core
    • Y10T29/49076—From comminuted material

Definitions

  • ABSTRACT r A method of adjusting the dimensions of sintered ferromagnetic coil cores by coating the cores in a mold with a layerrof coating material consisting of a binder Y and a ferromagnetic powder.
  • gthiS. object is achieved in that after sintering, before'the core is provided with a; winding to form a coil or transformer, at least a portion of the surface of the core is coated ina mold with a layer of coating material consisting of a mixture of a binder and a ferromagnetic powder The coating material can be pressed or injected into the mold in a known. manner. The ultimate surface of the.
  • coated portion of the core isan accurate impression of the corresponding surface of thernould.
  • The. coating material generally-has a lower magnetic permeability-than the sintered material of the .core. This means that in coils having an air gap" whose width isto be accurately defined, also'the thickness and the permeability of the coating materialhave t'o be'taken int'oaccount'for' calculatingthe-widthof the "air gap.
  • FIG. 1 is an axial sectional view of a cylindrical coil whose core is manufactured by the method according to the invention
  • FIG. 2 is a partly axial sectional view of a deflection coil assembly, the yoke ringofwhich has not been treated aftersintering, and
  • FIG. 3 is a partly axial sectional view .ofa deflection coil assembly whose yoke ringhas been given the correct' dimensions after sintering by themethod according to the invention.
  • the coil shown in FIG. 1 comprises a cylindrical winding 1 which is wound on a central cylinder 3 hav-' ing connecting wires 4.
  • This central cylinder will generally be ferromagnetic. If the central cylinder 3 is sintered from ferromagnetic material,-the dimensions of its outer surfacecan be controlled-without much difficulty, for example, by'centerless grinding. As a result, the outer diameter of the winding 1 has a small tolerance..
  • a hollow,.outer cylinder 5 made of sintered ferromagnetic material, said cylinder constituting the core of the coil in co'njunction with the central cylinder 3.
  • an air gap 6 Between the hollow outer cylinder 5 and the winding 1 is situated an air gap 6, the width tolerance of which is determined mainly by the variations possible in the inner diameter of the'outer cylinder 5.
  • the inner side of the outer cyIinderS is raised in a mold. by providing a layer of coating material 7,
  • a binder for example,polythene
  • a a thickness'd corresponds toi'an airgap having a width d/pJ.
  • a favorable compromise can .be ob-' tained by means of a coating material whose permeabilferromagnetic powder,'for example, ferrite;
  • the layer 7 partly fills the air gap 6.
  • Variations in the dimensions of the outer cylinder 5 merely cause thickness variations inthe layer 7, without affecting the width of the air-filledportion 8 of. the air gap 6.
  • the total effective width of the air gap 6 is equal to the width of the airfilled portion 8 plus the thickness of the layer 7, divided by the permeability of the coatingfmateriaLsaid permeability preferably amounting to 10;.
  • This rneansthat a variation of 0.1 .mm inthe-thickness of layer ,7, caused by the tolerance of the l1ollow. outer cylinder 5, corresponds to a'variation. of"only 0.0l .mm. inthe total'effective width of the air gap 6.
  • each of the connecting wires 4 can be secured-in'the (hollow) central cylinder by means of a plug 9 of the same material as the layer 7.
  • Th e plug 9 can be conity has a value of approximately 10 after hardening of the'binder. Thickness variations in the coating material tion of the plug 9 extending outsidethe central cylinthen correspond to 'width variations of the air gap whichfare 10 times as small, which is in view of the usual tolerances of sintered cores fullyacceptable for most applications.
  • r i It is to be noted that the surrounding of a coil bya moulding compound is known, for example, from Swiss Pat. Spec; No. 228,763. The windings of the coil, however, are then embedded in 'the moulding compound, after'they have been provided on the core, so as to increase the inductance, thus forming an integral unit.
  • Providing the winding 1 on the central cylinder 3 can be facilitated by imparting a conical surface to the porj der, so that a gradual change-over from the diameter of of saddle coils 11 for the frame deflection (the pair of line deflection coils provided within the frame coils is omitted for the sake of clarity).
  • the coil pair 11 is surrounded by a yoke ring-13 of sintered ferrite, having a flared inner surface which has not been treated after sintering.
  • the Figure clearly illustrates that a yoke ring 13 which has shrunk only slightly more than the ring 13, will take in a position which has shifted considerably in the axial direction.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Formation Of Various Coating Films On Cathode Ray Tubes And Lamps (AREA)
  • Soft Magnetic Materials (AREA)
  • Powder Metallurgy (AREA)
US00184696A 1970-10-09 1971-09-29 Method of adjusting the dimensions of sintered ferromagnetic cores Expired - Lifetime US3775841A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
NL7014813A NL7014813A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1970-10-09 1970-10-09
US18469671A 1971-09-29 1971-09-29
US00388256A US3829806A (en) 1970-10-09 1973-08-14 Sintered ferromagnetic core having accurately adjusted dimensions

Publications (1)

Publication Number Publication Date
US3775841A true US3775841A (en) 1973-12-04

Family

ID=27351608

Family Applications (2)

Application Number Title Priority Date Filing Date
US00184696A Expired - Lifetime US3775841A (en) 1970-10-09 1971-09-29 Method of adjusting the dimensions of sintered ferromagnetic cores
US00388256A Expired - Lifetime US3829806A (en) 1970-10-09 1973-08-14 Sintered ferromagnetic core having accurately adjusted dimensions

Family Applications After (1)

Application Number Title Priority Date Filing Date
US00388256A Expired - Lifetime US3829806A (en) 1970-10-09 1973-08-14 Sintered ferromagnetic core having accurately adjusted dimensions

Country Status (5)

Country Link
US (2) US3775841A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
DE (1) DE2146113A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
FR (1) FR2110320B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
GB (1) GB1322092A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
NL (1) NL7014813A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4264683A (en) * 1978-07-26 1981-04-28 Permacoraltair, Inc. Metallic inductor cores
US4647890A (en) * 1986-05-15 1987-03-03 Battelle Development Corporation Molded ferromagnetic return circuit for a solenoid

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5230113A (en) * 1975-09-02 1977-03-07 Sony Corp Deflecting device of in-line type color cathode-ray tube
DE2805562C2 (de) * 1978-02-10 1984-08-02 Kuka Schweissanlagen + Roboter Gmbh, 8900 Augsburg Vorrichtung zum Anschweißen eines Werkstücks mit rohrförmigem Querschnitt an der Schweißstelle an ein zweites Werkstück
NL8004200A (nl) * 1980-07-22 1982-02-16 Philips Nv Kunststofgebonden electromagnetische component en werkwijze voor het vervaardigen daarvan.
US5166655A (en) * 1988-02-16 1992-11-24 Gowanda Electronics Corporation Shielded inductor
US5015982A (en) * 1989-08-10 1991-05-14 General Motors Corporation Ignition coil
CN113776337B (zh) * 2021-10-15 2024-01-16 海宁市海铖电子有限公司 一种防开裂显微结构锰锌铁氧体磁芯均热烧结装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US476816A (en) * 1892-06-14 And alfred pfxnn
US683954A (en) * 1900-11-30 1901-10-08 Frederick Rohnert Telephone-transformer.
GB214780A (en) * 1923-11-13 1924-05-01 Sydney Harold Varnals Improvements in stationary electrical transformers
US2118291A (en) * 1936-05-06 1938-05-24 Commw Mfg Company Arc welding unit
US3325760A (en) * 1965-10-01 1967-06-13 Gen Motors Corp Electromagnet with resinous ferromagnetic cladding

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US476816A (en) * 1892-06-14 And alfred pfxnn
US683954A (en) * 1900-11-30 1901-10-08 Frederick Rohnert Telephone-transformer.
GB214780A (en) * 1923-11-13 1924-05-01 Sydney Harold Varnals Improvements in stationary electrical transformers
US2118291A (en) * 1936-05-06 1938-05-24 Commw Mfg Company Arc welding unit
US3325760A (en) * 1965-10-01 1967-06-13 Gen Motors Corp Electromagnet with resinous ferromagnetic cladding

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4264683A (en) * 1978-07-26 1981-04-28 Permacoraltair, Inc. Metallic inductor cores
US4647890A (en) * 1986-05-15 1987-03-03 Battelle Development Corporation Molded ferromagnetic return circuit for a solenoid

Also Published As

Publication number Publication date
NL7014813A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1972-04-11
FR2110320A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1972-06-02
GB1322092A (en) 1973-07-04
DE2146113A1 (de) 1972-04-13
FR2110320B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1976-06-04
US3829806A (en) 1974-08-13

Similar Documents

Publication Publication Date Title
US3775841A (en) Method of adjusting the dimensions of sintered ferromagnetic cores
GB2044550A (en) Case inductive circuit components
US4260974A (en) Deflection unit for a cathode-ray tube
GB1421988A (en) Toroidal deflection yoke having conductors wound in flyback manner
JPS60206122A (ja) チヨ−クコイル
JPH023288B2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
US3875543A (en) Toroidal core-coil combination with in situ molded end rings
JPS5916251A (ja) 偏向ヨ−クコアの製造方法
JP2656541B2 (ja) ロータリートランス
JPH0140171Y2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
JP2973440B2 (ja) ロータリートランスの製造方法
US3859719A (en) Method of making a toroidal core-coil combination with in situ molded end rings
JPS5970154A (ja) 小形電動機
KR100228437B1 (ko) Pcs 장치
JPS59128736A (ja) 偏向ヨ−クコアの製造方法
JPH062252Y2 (ja) チップインダクタンス素子
JPS634326B2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
JPH06260328A (ja) 円筒状異方性磁石およびその製造方法
SU54152A1 (ru) Способ изготовлени магнитных сердечников
JPH09180650A (ja) 偏向ヨーク
JPH01315118A (ja) 回転トランス部品の製造方法
KR0144201B1 (ko) 브라운관용 편향요크 코아
JPS62128507A (ja) ロ−タリ−トランス
JPS61126743A (ja) 陰極線管用磁気ヨ−ク
JPH03225901A (ja) ロータリートランス及びその製造方法