GB319942A - Improvements relating to loud speaker telephone instruments - Google Patents

Improvements relating to loud speaker telephone instruments

Info

Publication number
GB319942A
GB319942A GB2919728A GB2919728A GB319942A GB 319942 A GB319942 A GB 319942A GB 2919728 A GB2919728 A GB 2919728A GB 2919728 A GB2919728 A GB 2919728A GB 319942 A GB319942 A GB 319942A
Authority
GB
United Kingdom
Prior art keywords
diaphragm
attached
coils
pole plates
supported
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
GB2919728A
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.)
JOHN IVER BERNARD
Original Assignee
JOHN IVER BERNARD
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 JOHN IVER BERNARD filed Critical JOHN IVER BERNARD
Priority to GB2919728A priority Critical patent/GB319942A/en
Publication of GB319942A publication Critical patent/GB319942A/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
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only 
    • H04R1/24—Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges

Landscapes

  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
  • Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)

Abstract

319,942. Bernard, J. I. Oct. 10, 1928. Loud-speakers; magnetic instruments; diaphragms. - A soundreproducer of the moving-coil type has a diaphragm consisting of two or more re-entrant portions of conical shape to which are attached two or more driving coils located at different distances from the centre of the diaphragm. The diaphragm shown in Fig. 2, has re-entrant conical portions with coils k<1>, k<2>, and has an outer corrugated portion d attached to the baffle board l. The coils k<1>, k<2> may be wound on metallic spools to induce damping. The magnetic system consists of four electro or permanent magnets n<1> - - n<4>, Fig. 1, having pole plates p attached to the limbs q, the pole plates being supported on a framework r. The field coils m<5>, m<6>, Figs. 3, 4, may, be concentric with the diaphragm which may be supported by flexible arms e, attached at one end to the diaphragm, and at the other to the casing. The pole plates p have openings t to avoid closed air pockets. The Provisional Specification states that the diaphragm need not be of uniform thickness.
GB2919728A 1928-10-10 1928-10-10 Improvements relating to loud speaker telephone instruments Expired GB319942A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2919728A GB319942A (en) 1928-10-10 1928-10-10 Improvements relating to loud speaker telephone instruments

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2919728A GB319942A (en) 1928-10-10 1928-10-10 Improvements relating to loud speaker telephone instruments

Publications (1)

Publication Number Publication Date
GB319942A true GB319942A (en) 1929-10-03

Family

ID=10287679

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2919728A Expired GB319942A (en) 1928-10-10 1928-10-10 Improvements relating to loud speaker telephone instruments

Country Status (1)

Country Link
GB (1) GB319942A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2789161A (en) * 1951-04-05 1957-04-16 Joseph B Brennan Loud-speakers
US7515723B2 (en) 2000-12-26 2009-04-07 Anders Sagren Electro-acoustic converter with demountable diaphragm and voice coil assembly

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2789161A (en) * 1951-04-05 1957-04-16 Joseph B Brennan Loud-speakers
US7515723B2 (en) 2000-12-26 2009-04-07 Anders Sagren Electro-acoustic converter with demountable diaphragm and voice coil assembly
US7551746B2 (en) 2000-12-26 2009-06-23 Anders Sagren Drive unit for electro-acoustic converter with radially magnetized permanent magnetic bars

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