GB403778A - Improvements in or relating to permanent magnets - Google Patents

Improvements in or relating to permanent magnets

Info

Publication number
GB403778A
GB403778A GB2609432A GB2609432A GB403778A GB 403778 A GB403778 A GB 403778A GB 2609432 A GB2609432 A GB 2609432A GB 2609432 A GB2609432 A GB 2609432A GB 403778 A GB403778 A GB 403778A
Authority
GB
United Kingdom
Prior art keywords
magnet
piece
totley
steel
sheffield
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
GB2609432A
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.)
DARWINS Ltd
WALTER LEWIS MARRISON
Original Assignee
DARWINS Ltd
WALTER LEWIS MARRISON
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 DARWINS Ltd, WALTER LEWIS MARRISON filed Critical DARWINS Ltd
Priority to GB2609432A priority Critical patent/GB403778A/en
Publication of GB403778A publication Critical patent/GB403778A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R31/00—Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor
    • H04R31/006—Interconnection of transducer parts
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/02—Details
    • H04R9/025—Magnetic circuit
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2209/00—Details of transducers of the moving-coil, moving-strip, or moving-wire type covered by H04R9/00 but not provided for in any of its subgroups
    • H04R2209/024—Manufacturing aspects of the magnetic circuit of loudspeaker or microphone transducers

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Manufacturing & Machinery (AREA)
  • Road Signs Or Road Markings (AREA)
  • Hard Magnetic Materials (AREA)
  • Permanent Field Magnets Of Synchronous Machinery (AREA)

Abstract

403,778. Loud-speakers. DARWINS, Ltd., Fitzwilliam Works, Templeborough, Sheffield, and MARRISON, W. L., Prospect House, Totley Brook Road, Totley Rise, near Sheffield. Sept. 20, 1932, No. 26094. [Class 40 (iv).] A portion of a permanent magnet with a narrow air gap, such as is employed in loudspeakers &c., consists of magnet steel which is hardened by heat treatment, the part next the gap being further treated to soften it. In the arrangement shown the steel portion of the magnet consists of a cylinder 10 with a reduced end 11. The piece 10 is heated to about 1100‹ C. and air cooled or quenched and the end 11 then dipped into molten salt or lead at 790-840‹ C. The ends 14 of the magnet and second pole-piece 15 may be of soft iron. The junction of the pieces 10, 11 may be tapered. The body 10 may be screened by a ring of asbestos &c., during the second treatment. In a modification the piece 15 may be of magnet steel and the portion surrounding the air gap softened by a flame &c.
GB2609432A 1932-09-20 1932-09-20 Improvements in or relating to permanent magnets Expired GB403778A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2609432A GB403778A (en) 1932-09-20 1932-09-20 Improvements in or relating to permanent magnets

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2609432A GB403778A (en) 1932-09-20 1932-09-20 Improvements in or relating to permanent magnets

Publications (1)

Publication Number Publication Date
GB403778A true GB403778A (en) 1934-01-04

Family

ID=10238261

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2609432A Expired GB403778A (en) 1932-09-20 1932-09-20 Improvements in or relating to permanent magnets

Country Status (1)

Country Link
GB (1) GB403778A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2534819A (en) * 1947-02-27 1950-12-19 Jensen Mfg Company Magnetic structure for speakers
US3247331A (en) * 1954-07-30 1966-04-19 Rca Corp Magnetic structure for a loudspeaker

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2534819A (en) * 1947-02-27 1950-12-19 Jensen Mfg Company Magnetic structure for speakers
US3247331A (en) * 1954-07-30 1966-04-19 Rca Corp Magnetic structure for a loudspeaker

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