US3418437A - Electro-acoustic transducer having a resonator cavity damped - Google Patents

Electro-acoustic transducer having a resonator cavity damped Download PDF

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Publication number
US3418437A
US3418437A US471367A US47136765A US3418437A US 3418437 A US3418437 A US 3418437A US 471367 A US471367 A US 471367A US 47136765 A US47136765 A US 47136765A US 3418437 A US3418437 A US 3418437A
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US
United States
Prior art keywords
electro
capillary
membrane
diaphragm
acoustic transducer
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
US471367A
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English (en)
Inventor
Munich Helmut Hoffmann
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.)
Siemens AG
Siemens Corp
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Siemens Corp
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Filing date
Publication date
Application filed by Siemens Corp filed Critical Siemens Corp
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Publication of US3418437A publication Critical patent/US3418437A/en
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Classifications

    • 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
    • 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 

Definitions

  • This invention concerns an electro-acoustic transducer, and more particularly, such a transducer having a resonator cavity provided with a coupling opening having a damping cover.
  • Such covers are used, for example, to improve the oscillation behavior of the diaphragm of a transducer such as by compensation for the resonance of the diaphragm.
  • the objects of the invention are achieved through use of the capillary zone of an ionotropic membrane as a damping cover.
  • a membrane can be produced by ionic diffusion into polyelectrolytes in accordance with processes such as those described in German Patents Nos. 1,011,853 and 1,108,665 in the name of Dr. Heinrich Thiele. Such process is also disclosed, inter alia, in British Patent No. 918,626.
  • ionotropic membranes are formed employing polyuronides as polyelectrolytes and polyvalent ions such as lead, copper, cadmium and calcium.
  • the polyvalent ion is permitted to diffuse into the polyelectrolyte to form straight, parallel and uniform capillaries as the polyelectrolyte coagulates into a membrane.
  • a dense primary membrane upon which a droplike separating zone is formed, with an adjoining capillary zone then formed.
  • the diameters of the capillary tubes can be controlled by variation of the chain length and concentration of the polyelectrolyte, as well as the radius and valence of the diffused ion.
  • the capillary zone of the membrane can be separated and stabilized by, for instance, introducing an artificial material into the walls thereof.
  • a damping cover according to the invention can be achieved in a particularly simple fashion.
  • the vibrating diaphragm itself can be formed by an ionotropic capillary membrane, with the previously mentioned dense primary membrane forming the main body of the diaphragm but being removed from the capillary zone thereof over a portion of the membrane corresponding to the coupling opening. The exposed capillary zone then forms the damping cover of the coupling opening, as before.
  • an ionotropic capillary membrane possesses a very desirable structure for use as a vibratory diaphragm, because of the complete uniformity of its construction and because of the low weight thereof due to the large number of capillary tubes therein.
  • the single figure is a cross-sectional view of a dynamic microphone constructed in accordance with the invention.
  • the microphone includes a casing 1 mounting a permanent magnet 2 carrying a central pole plate 3 which is radially inward of an annular pole ring 4 fixed to the casing.
  • a vibration diaphragm 5 carries the usual moving coil 6 and is clamped between spacing rings 7 and 8, covered by perforated lid or cover 9.
  • the annular pole ring 4 has a pair of openings or passages 10 and 11, therethrough, to provide for acoustic coupling to the resonator cavities 12 and 13, respectively. These passages are provided with respective damping covers 14 and 15, the damping covers being formed by the capillary zones of ionotropic capillary membranes.
  • the diaphragm 5 is similarly provided with a coupling opening 16 which couples the outer chamber between the cover 9 and diaphragm 5 with the inner chamber including resonator cavities 12 and 13.
  • the vibratory diaphragm 5 may itself be an ionotropic capillary membrane with the dense primary membrane facing the cover 9, but with a portion of that primary membrane removed to form the coupling opening or passage 16. Then, the remaining capillary zone of the membrane forms the damping cover for such passage.
  • a damping cover for such opening formed by the capillary zone of an ionotropic capillary mem' brane.
  • An electro-acoustic transducer having a resonator chamber and a vibratory diaphragm forming a wall of said chamber and provided with an acoustic passage therethrough for coupling the chamber to a sound source, the diaphragm being an ionotropic capillary membrane having a dense primary membrane layer at one side thereof and a capillary zone at the opposite side, the acoustic passage being formed by a portion of the capillary zone not covered by said primary membrane layer.
  • a dynamic microphone including a casing having a perforate cover thereon for acoustic coupling inward thereof, a permanent magnet, means defining a magnetic circuit for said permanent magnet with a cylindrical air gap therein, a vibratory diaphragm mounted adjacent said cover in said casing and carrying a moving coil extending into said cylindrical air gap to develop .a voltage thereacross in response to vibration of the diaphragm, said diaphragm being an ionotropic capillary membrane having a dense primary membrane layer next adjacent said cover and a capillary zone at the opposite side thereof, and an acoustic passage through said diaphragm formed by a portion of the capillary zone not covered by said primary 15 membrane layer.
  • said means defining a magnetic circuit includes an annular pole ring mourted in said casing and having at least one acoustic passage therethrough for sound coupling purposes, said passage being covered by the capillary zone of an ionotropic capillary membrane.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
  • Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
US471367A 1964-07-29 1965-07-12 Electro-acoustic transducer having a resonator cavity damped Expired - Lifetime US3418437A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DES92326A DE1216367B (de) 1964-07-29 1964-07-29 Elektroakustischer Wandler mit zumindest einem Resonatorraum, der durch eine mit einer Daempfungsabdeckung versehene OEffnung angekoppelt ist
DES92323A DE1259949B (de) 1964-07-29 1964-07-29 Elektroakustischer Wandler mit beiderseits einer Schwingmembran liegenden akustisch wirksamen Raeumen

Publications (1)

Publication Number Publication Date
US3418437A true US3418437A (en) 1968-12-24

Family

ID=25997735

Family Applications (1)

Application Number Title Priority Date Filing Date
US471367A Expired - Lifetime US3418437A (en) 1964-07-29 1965-07-12 Electro-acoustic transducer having a resonator cavity damped

Country Status (6)

Country Link
US (1) US3418437A (en:Method)
BE (1) BE667646A (en:Method)
DE (2) DE1216367B (en:Method)
GB (1) GB1082433A (en:Method)
NL (1) NL6509262A (en:Method)
SE (1) SE313598B (en:Method)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3646281A (en) * 1969-06-02 1972-02-29 Rdf West Electrostatic transducer with vented diaphragm
US3930560A (en) * 1974-07-15 1976-01-06 Industrial Research Products, Inc. Damping element
US4005278A (en) * 1974-09-16 1977-01-25 Akg Akustische U. Kino-Gerate Gesellschaft M.B.H. Headphone
US4030564A (en) * 1973-06-28 1977-06-21 Pioneer Electronic Corporation Loud speaker with stable damping
US4602245A (en) * 1983-04-29 1986-07-22 Ensco, Inc. General purpose modular acoustic signal generator
US4843628A (en) * 1986-07-10 1989-06-27 Stanton Magnetics, Inc. Inertial microphone/receiver with extended frequency response
US4858719A (en) * 1986-01-16 1989-08-22 Akg Akustische U. Kino-Gerate Gesellschaft M.B.H. Pressure gradient pickup
US20060254852A1 (en) * 2005-05-11 2006-11-16 Yen-Shan Chen Integral audio module
US8479992B2 (en) 2003-11-13 2013-07-09 Metrologic Instruments, Inc. Optical code symbol reading system employing an acoustic-waveguide structure for coupling sonic energy, produced from an electro-transducer, to sound wave ports formed in the system housing
US20150256922A1 (en) * 2012-10-18 2015-09-10 Nokia Technologies Oy Resonance Damping for Audio Transducer Systems
US10299030B2 (en) * 2015-03-25 2019-05-21 Goertek Inc. Speaker module with sealed cavity and a communicating hole
USD867346S1 (en) * 2018-01-19 2019-11-19 Dynamic Ear Company B.V. Ambient filter

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3530869A1 (de) * 1985-08-29 1987-03-12 Sennheiser Electronic Membran fuer einen elektroakustischen wiedergabewandler

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1011953B (de) 1956-04-07 1957-07-11 Rosenthal Isolatoren Ges Mit B Befestigungsvorrichtung fuer ein elektrisches Freileitungsseil an einem Stuetzenisolator

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3646281A (en) * 1969-06-02 1972-02-29 Rdf West Electrostatic transducer with vented diaphragm
US4030564A (en) * 1973-06-28 1977-06-21 Pioneer Electronic Corporation Loud speaker with stable damping
US3930560A (en) * 1974-07-15 1976-01-06 Industrial Research Products, Inc. Damping element
US4005278A (en) * 1974-09-16 1977-01-25 Akg Akustische U. Kino-Gerate Gesellschaft M.B.H. Headphone
US4602245A (en) * 1983-04-29 1986-07-22 Ensco, Inc. General purpose modular acoustic signal generator
US4858719A (en) * 1986-01-16 1989-08-22 Akg Akustische U. Kino-Gerate Gesellschaft M.B.H. Pressure gradient pickup
US4843628A (en) * 1986-07-10 1989-06-27 Stanton Magnetics, Inc. Inertial microphone/receiver with extended frequency response
US8479992B2 (en) 2003-11-13 2013-07-09 Metrologic Instruments, Inc. Optical code symbol reading system employing an acoustic-waveguide structure for coupling sonic energy, produced from an electro-transducer, to sound wave ports formed in the system housing
US9104930B2 (en) 2003-11-13 2015-08-11 Metrologic Instruments, Inc. Code symbol reading system
US20060254852A1 (en) * 2005-05-11 2006-11-16 Yen-Shan Chen Integral audio module
US20150256922A1 (en) * 2012-10-18 2015-09-10 Nokia Technologies Oy Resonance Damping for Audio Transducer Systems
US20170289674A1 (en) * 2012-10-18 2017-10-05 Nokia Technologies Oy Resonance Damping for Audio Transducer Systems
US9813802B2 (en) * 2012-10-18 2017-11-07 Nokia Technologies Oy Resonance damping for audio transducer systems
US10085086B2 (en) * 2012-10-18 2018-09-25 Nokia Technologies Oy Resonance damping for audio transducer systems
US10299030B2 (en) * 2015-03-25 2019-05-21 Goertek Inc. Speaker module with sealed cavity and a communicating hole
USD867346S1 (en) * 2018-01-19 2019-11-19 Dynamic Ear Company B.V. Ambient filter

Also Published As

Publication number Publication date
GB1082433A (en) 1967-09-06
SE313598B (en:Method) 1969-08-18
DE1259949B (de) 1968-02-01
DE1216367B (de) 1966-05-12
NL6509262A (en:Method) 1966-01-31
BE667646A (en:Method) 1966-01-31

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