EP0050303B1 - Process for manufacturing magnetic pole assembly - Google Patents

Process for manufacturing magnetic pole assembly Download PDF

Info

Publication number
EP0050303B1
EP0050303B1 EP81108300A EP81108300A EP0050303B1 EP 0050303 B1 EP0050303 B1 EP 0050303B1 EP 81108300 A EP81108300 A EP 81108300A EP 81108300 A EP81108300 A EP 81108300A EP 0050303 B1 EP0050303 B1 EP 0050303B1
Authority
EP
European Patent Office
Prior art keywords
magnetic
members
magnetic pole
openings
pair
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
Application number
EP81108300A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0050303A1 (en
Inventor
Mamoru Uchikune
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.)
Kanetsu Kogyo KK
Original Assignee
Kanetsu Kogyo KK
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 Kanetsu Kogyo KK filed Critical Kanetsu Kogyo KK
Publication of EP0050303A1 publication Critical patent/EP0050303A1/en
Application granted granted Critical
Publication of EP0050303B1 publication Critical patent/EP0050303B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • 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

Definitions

  • This invention relates to a process for manufacturing a magnetic pole assembly having non-magnetic members and a pair of magnetic pole members coupled together with the non-magnetic members interposed therebetween, and more particularly to a process for manufacturing a magnetic pole assembly suited for a magnetic circuit block for a switchable permanent magnet device.
  • the non-magnetic members are formed in a desired shape beforehand; then a pair of magnetic pole members are disposed with non-magnetic members of a desired configuration interposed therebetween, and the pair of magnetic pole members and the non-magnetic members are integrally coupled to each other by introducing the non-magnetic members into the openings of the pole members.
  • the prior art process requires the steps of forming a non-magnetic member in a desired configuration, and coupling a pair of magnetic pole members to each other, with the non-magnetic members of a desired configuration interposed therebetween.
  • the prior art process has suffered from misalignment of one member from the other particularly in the coupling step, thus requiring a cutting or grinding step for making the surfaces of these components in alignment.
  • an object of the present invention to provide a process for manufacturing a magnetic pole assembly, which is reduced in number of manufacturing. steps, for the simplicity sake.
  • a process for manufacturing a magnetic pole assembly said magnetic pole assembly having non-magnetic members, a pair of magnetic pole members coupled together, with said non-magnetic members interposed between and holding them together in position, the magnetic pole members each including openings each having one end opening into the surface opposing the other magnetic member, characterized by the step of moulding said non-magnetic members by using as part of mould said pair of magnetic pole members disposed in opposed relation to and at a given spacing from each other, thereby coupling said pair of magnetic pole members to each other through the medium of said non-magnetic members.
  • FIG. 1 there is shown in an exploded state a magnet base 12 including a magnetic pole assembly 10 which has been made by the process of the present invention.
  • the magnet base namely switchable permanent magnet device 12, comprises a magnetic pole assembly 10, a columnar permanent magnet 14 rotatably received in a bore 12' in the magnetic pole assembly and magnetized in a diametrical direction, a knob 16 for rotating the permanent magnet, and an end plate 17 for holding the knob thereon rotatably.
  • the knob 16 By turning the knob 16, the bottom surfaces 10a of the magnetic pole assembly 10 becomes magnetized or demagnetized as is well khown.
  • the magnet base 12 in general, is used for supporting various instruments, such as measuring instruments, through the medium of a support pole or leg which is attached to the top surface of the magnetic pole assembly 10, which in turn is attached at the lower surfaces 10a thereof to a magnetic plate by magnetic attraction.
  • the magnetic pole assembly 10 which is a magnetic circuit block for receiving the permanent magnet 14 rotatably, includes a pair of opposing magnetic pole members 18 made of a magnetic material, such as soft iron, and non-magnetic members 20 interposed therebetween.
  • the pair of magnetic pole members 18 are respectively formed in a given configuration, for example, by a cold drawing process.
  • recesses 22 Provided in the opposing surfaces 18a of the pair of magnetic pole members 18 are recesses 22 having a semicircular cross section, so that these recesses cooperate to define the central bore 12' for receiving therein the permanent magnet 14, as best seen in Fig. 2.
  • the recesses 22 are open from the opposite ends of the magnetic pole members 18, respectively.
  • Plural pairs of threaded holes 24 are provided in the opposing magnetic pole members 18 in the upper and lower portions thereof i.e. on the both sides of each recess 22.
  • One threaded hole 24 runs parallel to another threaded hole in each magnetic pole member, with one end open to the surface 18a, and with the other inner end closed. It is possible that each threaded hole 24 be open at the opposite ends thereof. However, in the latter case, after a non-magnetic material has been cast into each threaded hole, which will be described later, a finishing step for closing the other end of each threaded hole is required, so as to provide a neat appearance for the magnetic pole assembly 10.
  • each threaded hole is a blind end.
  • the non-magnetic members 20 between the opposing magnetic pole members 18 are formed by a molding process by using these magnetic pole members 18 as part of the mold. More in detail, the magnetic pole members 18 are incorporated in a molding device (not shown) in a manner that the recess 22 of one magnetic pole member 18 opposes the recess 22 of the other member at a given spacing therefrom. In order to ensure the bore 12', a columnar core (not shown), having an outer diameter slightly larger than the outer diameter of the permanent magnet 14, is placed in the central bore defined by the recesses 22 of the opposing magnetic pole members 18 incorporated in the molding device.
  • non-magnetic molten metal such as aluminum or zinc
  • non-magnetic molten resin such as ABS synthetic resin
  • the non-magnetic members 20 are molded by using the magnetic pole members 18 as part of the mold, as described, a lid 26 closing one end of the bore 12' and molten materials 28 are simultaneously cast into the threaded holes 24 (hereinafter referred to as cast portions) and are integrally formed with the respective non-magnetic members 20 in the manner shown in Fig. 1.
  • the cast portions 28 are firmly retained in corresponding threaded hole 24 due to shrinkage stress resulting from the cooling of these portions.
  • the opposing magnetic pole members 18 are integrally coupled together through the medium of the cast portions 28 of respective non-magnetic members 20.
  • non-magnetic members 20 In order to form the non-magnetic members 20, it is preferable to employ so-called die casting. In case of forming the non-magnetic members 20, it is recommended to provide in the non-magnetic members tapped threaded holes 32 for receiving therein screws 30 for fixing the end plate 17 to the magnetic pole assembly 10 and a female threaded hole 34 for receiving the aforesaid support pole or leg. In this connection, a strong tightening force acts on the female threaded hole 34 when the support pole or leg is threadedly fitted therein, and the strong tightening force is developed into a strong expansion force which would act on the peripheral portion of the threaded hole 34, of the non-magnetic member 20.
  • the pair of cast portions 28 located on the opposite sides of the threaded hole 34 in the coupling portion between the opposing magnetic pole members 18 contribute to preventing the upper non-magnetic member 20 being deformed due to the strong expansion force.
  • the lid 26 is formed integrally with the upper and lower non-magnetic members.20, the lid may be formed separately from the non-magnetic members 20. However, from the viewpoint of simplicity in manufacturing steps, it is recommended to form the lid 26 integrally with the non-magnetic members 20, as described above.
  • the threaded holes 24 provided in respective magnetic pole member 18 may be holes 36 having no threads, as shown in Fig. 3(a). Also, in the case of the non-threaded holes, the opposing magnetic pole members 18 and the non-magnetic members 20 are firmly coupled together by the cast portions 28 due to shrinkage stress resulting from the cooling of these portions, likewise in the threaded holes.
  • a diametrically reduced portion 36a is provided at the circumferential edge of the open end thereof, in the manner shown in Fig. 3(b).
  • the diametrically reduced portions 36a of respective holes 36 ensure a stronger coupling between the magnetic pole members 18 and the non-magnetic members 20.
  • a pair of holes 36 in each magnetic pole member 18 may run, with their axes running non-parallel, as shown in Fig. 4, or otherwise.
  • the adjacent holes 36 may cross each other at the inner ends thereof, as shown in Fig. 5, with the result that a strong coupling between the opposing magnetic pole members and the magnetic members is ensured.
  • the opposing magnetic pole members 18 are integrally coupled together through the medium of the non-magnetic members 20. The number of manufacturing steps is thus reduced.
  • the bore 12' for receiving the permanent magnet 14 is provided with high accuracy by formation of the non-magnetic members 20, so that the non-magnetic members 20 have no likelihood of protruding into the bore 12'.
  • a cutting or grinding step for the inner peripheral wall of the bore is no longer needed.
  • lid 26 for closing one end of the bore 12' is formed integrally with the non-magnetic members 20, a step for closing the ends of the bore by another material is eliminated.
  • the non-magnetic member means is formed between the pair of opposing magnetic pole members having holes in the opposing surfaces thereof, by using the magnetic pole members as part of the mold, whereby the non-magnetic member means is formed, and at the same time, the pair of opposing magnetic pole members and the non-magnetic member means are firmly coupled to each other with high accuracy through the medium of the cast portions in the aforesaid holes, whereby simplicity of the manufacturing process is attained and an inexpensive and highly accurate magnet assembly is obtained.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Electromagnets (AREA)
  • Magnetic Resonance Imaging Apparatus (AREA)
  • Dynamo-Electric Clutches, Dynamo-Electric Brakes (AREA)
EP81108300A 1980-10-17 1981-10-14 Process for manufacturing magnetic pole assembly Expired EP0050303B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP55144455A JPS6029206B2 (ja) 1980-10-17 1980-10-17 磁極体の製造方法
JP144455/80 1980-10-17

Publications (2)

Publication Number Publication Date
EP0050303A1 EP0050303A1 (en) 1982-04-28
EP0050303B1 true EP0050303B1 (en) 1985-05-02

Family

ID=15362642

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81108300A Expired EP0050303B1 (en) 1980-10-17 1981-10-14 Process for manufacturing magnetic pole assembly

Country Status (7)

Country Link
EP (1) EP0050303B1 (enExample)
JP (1) JPS6029206B2 (enExample)
KR (1) KR850000858B1 (enExample)
BR (1) BR8100718A (enExample)
DE (1) DE3170319D1 (enExample)
GB (1) GB2085659B (enExample)
IN (1) IN153290B (enExample)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010106409A1 (en) * 2009-03-19 2010-09-23 Robert Bosch Gmbh Magnetic locking system

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB523747A (en) * 1938-12-03 1940-07-22 Landis & Gyr Ag Improvements in or relating to permanent brake magnets of high coercive force
GB894518A (en) * 1959-09-16 1962-04-26 Ass Elect Ind Improvements in or relating to permanent magnets
GB1571057A (en) * 1976-01-28 1980-07-09 Sev Marchal Magnetic circuits

Also Published As

Publication number Publication date
BR8100718A (pt) 1982-08-17
JPS5769713A (en) 1982-04-28
EP0050303A1 (en) 1982-04-28
GB2085659B (en) 1984-05-31
JPS6029206B2 (ja) 1985-07-09
KR850000858B1 (ko) 1985-06-17
DE3170319D1 (en) 1985-06-05
GB2085659A (en) 1982-04-28
IN153290B (enExample) 1984-06-30
KR830008356A (ko) 1983-11-18

Similar Documents

Publication Publication Date Title
US4575117A (en) Striking energy absorbing structure for steering wheel and method of manufacturing the same
EP0050303B1 (en) Process for manufacturing magnetic pole assembly
US3530022A (en) Method of making interchangeable medallions for plastic mat-forming molds
JPS5961008A (ja) リング状異方性磁石の製造方法
US5318095A (en) Die cast magnet assembly and method of manufacture
US5637327A (en) Mold with recess for convex insert portion
JPH0239368B2 (ja) Jushifushigatahandotaisochiseikeiyomoorudokanagata
JPS5919412Y2 (ja) リング状樹脂マグネットの成形金型
JPH0714903Y2 (ja) 可動磁石型計器
JPS6355768B2 (enExample)
JPS5919411Y2 (ja) リング状樹脂マグネットの成形金型
JPH02305A (ja) プラスチック磁石
JP2800458B2 (ja) 異方性プラスチックマグネットの磁場成形装置
JPS61266216A (ja) 射出成形用金型
JPH0727833B2 (ja) プラスチツク磁石の製造方法
JPS55123117A (en) Molded stationary equipment and its manufacte
JPS60933B2 (ja) 電磁鉄心のインサ−ト成型方法
KR890004157Y1 (ko) 플라스틱 밸브의 플렌지 보울트공 성형장치
SU939229A1 (ru) Литьева пресс-форма дл изготовлени полых изделий сложной конфигурации
JPH0529464Y2 (enExample)
KR101189453B1 (ko) 왕복동식 모터의 마그네트프레임 구조 및 그 금형
JP3398946B2 (ja) 記録ディスクのシャッター成形用金型装置
JPS59151421U (ja) 異方性樹脂磁石の射出成形用金型
JPH02213110A (ja) コイルボビンの製造型
JPH06210673A (ja) 異方性樹脂磁石成形用金型

Legal Events

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

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): DE FR IT NL

ITCL It: translation for ep claims filed

Representative=s name: INGG. GUZZI RAVIZZA

17P Request for examination filed

Effective date: 19820406

TCNL Nl: translation of patent claims filed
DET De: translation of patent claims
ITF It: translation for a ep patent filed
GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): DE FR IT NL

REF Corresponds to:

Ref document number: 3170319

Country of ref document: DE

Date of ref document: 19850605

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
ITTA It: last paid annual fee
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19991018

Year of fee payment: 19

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

Ref country code: NL

Payment date: 19991027

Year of fee payment: 19

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

Ref country code: DE

Payment date: 19991129

Year of fee payment: 19

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010501

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010629

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20010501

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010703

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST