FR664413A - Improvements to telephones, in particular speakerphones - Google Patents

Improvements to telephones, in particular speakerphones

Info

Publication number
FR664413A
FR664413A FR664413DA FR664413A FR 664413 A FR664413 A FR 664413A FR 664413D A FR664413D A FR 664413DA FR 664413 A FR664413 A FR 664413A
Authority
FR
France
Prior art keywords
speakerphones
telephones
particular speakerphones
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
Other languages
French (fr)
Inventor
Archibald Parker Welch
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 filed Critical
Application granted granted Critical
Publication of FR664413A publication Critical patent/FR664413A/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
    • H04R7/00—Diaphragms for electromechanical transducers; Cones
    • H04R7/16—Mounting or tensioning of diaphragms or cones
    • H04R7/18—Mounting or tensioning of diaphragms or cones at the periphery
    • H04R7/20—Securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
FR664413D 1927-07-19 1928-11-21 Improvements to telephones, in particular speakerphones Expired FR664413A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1916227A GB297539A (en) 1927-07-19 1927-07-19 Improvements in or relating to sound reproducing devices such as loud speakers

Publications (1)

Publication Number Publication Date
FR664413A true FR664413A (en) 1929-09-03

Family

ID=10124790

Family Applications (1)

Application Number Title Priority Date Filing Date
FR664413D Expired FR664413A (en) 1927-07-19 1928-11-21 Improvements to telephones, in particular speakerphones

Country Status (3)

Country Link
CH (1) CH136431A (en)
FR (1) FR664413A (en)
GB (1) GB297539A (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2694463A (en) * 1952-04-07 1954-11-16 Robbins Frank Acoustic system for loud-speakers
DE102007023443B3 (en) * 2007-05-19 2008-11-06 Boris Kobuladze Dynamic loudspeaker for flat devices, particularly flat television, has convex diaphragm, unit for attachment of edge of diaphragm to housing of loudspeaker and pair of permanent magnet and electrical coil

Also Published As

Publication number Publication date
GB297539A (en) 1928-09-27
CH136431A (en) 1929-11-15

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