EP0370846B1 - Electroacoustic transducer - Google Patents

Electroacoustic transducer Download PDF

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Publication number
EP0370846B1
EP0370846B1 EP89402966A EP89402966A EP0370846B1 EP 0370846 B1 EP0370846 B1 EP 0370846B1 EP 89402966 A EP89402966 A EP 89402966A EP 89402966 A EP89402966 A EP 89402966A EP 0370846 B1 EP0370846 B1 EP 0370846B1
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EP
European Patent Office
Prior art keywords
electrodes
electroacoustic transducer
transducer according
ion
electrode
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Expired - Lifetime
Application number
EP89402966A
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German (de)
French (fr)
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EP0370846A1 (en
Inventor
Jean-Claude Fourriere
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Acieries Du Haut Languedoc SA
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Acieries Du Haut Languedoc SA
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Priority to AT89402966T priority Critical patent/ATE92701T1/en
Publication of EP0370846A1 publication Critical patent/EP0370846A1/en
Application granted granted Critical
Publication of EP0370846B1 publication Critical patent/EP0370846B1/en
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R23/00—Transducers other than those covered by groups H04R9/00 - H04R21/00
    • H04R23/004—Transducers other than those covered by groups H04R9/00 - H04R21/00 using ionised gas

Definitions

  • the present invention relates to an electroacoustic transducer, as well as an acoustic enclosure comprising at least one such transducer.
  • an electroacoustic transducer comprising a wire capable of emitting ions when it is brought to a sufficiently high potential, said wire being arranged between two electrodes, one parallel to the other, connected to a modulator, between which is likely to be created a modulated electric field acting on said ions. Said ions are then set in motion and transmit, by collisions, the energy thus acquired to the surrounding neutral molecules, producing a sound at the frequency of the modulated electric field.
  • the emission of ions is very localized, in the immediate vicinity of the wire, so that the results obtained are hardly satisfactory in practice.
  • an electroacoustic transducer of the type comprising at least one element capable of emitting ions when it is brought to a sufficiently high electrical potential, said element being arranged at neighborhood of two first electrodes, parallel to each other, connected to a modulator, between which a modulated electric field is likely to be created, and at least a second electrode having an electrical potential such as a flux of ions are created between said ion emitter and said second electrode, so that said modulated electric field acts on said ion flux.
  • the present invention aims to improve the latter transducer, and relates to an electroacoustic transducer whose efficiency is greatly improved.
  • the transducer of the type described in document US-A-3 022 385 is characterized in that said ion-emitting element is arranged between said two first electrodes, and in that said second electrode is arranged in the vicinity of said ion emitting element so that said ion flow forms a vibrating membrane between said ion emitting element and said second electrode.
  • said ion flow plays the role of an immaterial vibrating membrane.
  • the ionized fluid, created between the ion-emitting element and the second electrode is attracted by the first electrodes at the rate of the modulation, thereby generating acoustic pressures in the air.
  • said ion emitting element is a wire
  • two said second parallel electrodes are provided on either side of said wire respectively, said second electrodes being orthogonal to said first electrodes.
  • said second electrodes are arranged at equal distances from said wire.
  • the latter in particular in stainless steel or platinum, can have a diameter of between 20 and 50 micrometers.
  • said ion emitting element is a point
  • either a plurality of second point electrodes are arranged in a fan around said point, or said second electrode has approximately the shape of a horseshoe surrounding said point.
  • said first electrodes are arranged at equal distances from said ion emitting element.
  • said first electrodes are grids of rigid textile material covered with carbon.
  • said ion-emitting element is brought to a negative potential of the order of at least -4.5 kV.
  • Figures 1 and 2 illustrate a first embodiment of the electroacoustic transducer of the invention, in which the ion emitting element is a wire.
  • Figures 3 and 4, and 5 and 6 illustrate, respectively, two variants of a second embodiment of the electroacoustic transducer of the invention, in which the ion emitting element is a tip.
  • the electroacoustic transducer 1 comprises a wire 2, connected to a high voltage source 3, capable of emitting ions when it is brought to a sufficiently high electrical potential, for example a negative potential of the order of - 4.5 kV at least, negative potential giving no discharge noises.
  • the wire 2 is arranged between two first electrodes 4,5, parallel to each other, connected to a modulator 6 via a transformer 7.
  • a modulated electric field can thus be created between the two electrodes 4 , 5, to act on said ions.
  • the electrodes 4,5 are advantageously produced in the form of grids of rigid textile material covered with carbon. As a result, the formation of arcs in the presence of strong modulations is extremely rare, and these are not maintained as they would be with metal grids.
  • first 4.5 and second 8.9 electrodes are advantageously arranged at equal distances from the wire, respectively, so as to avoid creating an ionic wind during the application of the negative voltage. of polarization.
  • the modulated electric field created between the first electrodes 4,5 thus acts on the ion flow 10, generated between the wire 2 and the second electrodes 8,9, playing the role of a non-material vibrating membrane.
  • the ionized fluid created between the wire 2 and the ground electrodes 8, 9 is attracted by the grids 4.5 at the rate of the modulation, thereby producing acoustic pressures in the air.
  • the ion-emitting wire is replaced by a tip.
  • the tip 11 is arranged in a support ring 12, so that the tip 11a thereof is located in the center of said ring 12.
  • the tip 11 connected to a high voltage source 13 is capable of emitting ions when it is brought to a sufficiently high electrical potential, for example a negative potential of the order of -4.5 kV.
  • the tip 11, and in particular the tip 11a thereof is arranged between two first electrodes 14,15, parallel to each other, connected to a modulator 16 by means of a transformer 17.
  • These electrodes 14,15 are advantageously of the same type as the electrodes 4,5 described above.
  • a plurality of second point electrodes 18 (for example three electrodes 18), connected to ground, are arranged in a fan around the end 11a of the tip 11.
  • a second single electrode 19 connected to ground, having approximately the shape of a horseshoe surrounds the tip 11a of the tip 11.
  • the modulated electric field created between the first electrodes 14,15 and the tip 11 acts on the ion flow 20, generated between the tip 2 and the second electrode (s) 18,19, playing the role of immaterial vibrating membrane.

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  • 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)
  • Transducers For Ultrasonic Waves (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)

Abstract

- The present invention relates to an electroacoustic transducer, comprising at least one element (2) capable of emitting ions when it is brought to a sufficiently high electrical potential, the said element being arranged between two first electrodes (4, 5), which are parallel to one another and connected to a modulator (6), and between which a modulated electric field acting on the said ions is capable of being created. - According to the invention, it comprises at least one second electrode (8, 9) which is brought to an electrical potential such that a flux of ions (10) is created between the said emitter of ions (2) and the said second electrode (8, 9), and which is disposed in the vicinity of the said ion emitting element (2) so that the said modulated electric field acts on the said flux of ions (10). - The invention applies to acoustic enclosures. <IMAGE>

Description

La présente invention concerne un transducteur électroacoustique, ainsi qu'une enceinte acoustique comportant au moins un tel transducteur.The present invention relates to an electroacoustic transducer, as well as an acoustic enclosure comprising at least one such transducer.

On connaît déjà, par le document FR-A-2 246 151, un transducteur électroacoustique comportant un fil susceptible d'émettre des ions lorsqu'il est porté à un potentiel suffisamment élevé, ledit fil étant agencé entre deux électrodes, parallèles l'une à l'autre, reliées à un modulateur, entre lesquelles est susceptible d'être créé un champ électrique modulé agissant sur lesdits ions. Lesdits ions sont alors mis en mouvement et transmettent, par collisions, l'énergie ainsi acquise aux molécules neutres environnantes, en produisant un son à la fréquence du champ électrique modulé. Cependant, dans ce cas, l'émission d'ions est très localisée , au voisinage immédiat du fil, de sorte que les résultats obtenus ne sont guère satisfaisants en pratique.Already known from document FR-A-2 246 151, an electroacoustic transducer comprising a wire capable of emitting ions when it is brought to a sufficiently high potential, said wire being arranged between two electrodes, one parallel to the other, connected to a modulator, between which is likely to be created a modulated electric field acting on said ions. Said ions are then set in motion and transmit, by collisions, the energy thus acquired to the surrounding neutral molecules, producing a sound at the frequency of the modulated electric field. However, in this case, the emission of ions is very localized, in the immediate vicinity of the wire, so that the results obtained are hardly satisfactory in practice.

Par ailleurs, par le document US-A-3 022 385, on connaît un transducteur électroacoustique, du type comportant au moins un élément susceptible d'émettre des ions lorsqu'il est porté à un potentiel électrique suffisamment élevé, ledit élément étant agencé au voisinage de deux premières électrodes, parallèles l'une à l'autre, reliées à un modulateur, entre lesquelles est susceptible d'être créé un champ électrique modulé, et au moins une seconde électrode ayant un potentiel électrique tel qu'un flux d'ions est créé entre ledit émetteur d'ions et ladite seconde électrode, de sorte que ledit champ électrique modulé agisse sur ledit flux d'ions.Furthermore, from document US-A-3 022 385, an electroacoustic transducer is known, of the type comprising at least one element capable of emitting ions when it is brought to a sufficiently high electrical potential, said element being arranged at neighborhood of two first electrodes, parallel to each other, connected to a modulator, between which a modulated electric field is likely to be created, and at least a second electrode having an electrical potential such as a flux of ions are created between said ion emitter and said second electrode, so that said modulated electric field acts on said ion flux.

La présente invention a pour but de perfectionner ce dernier transducteur, et concerne un transducteur électroacoustique dont l'efficacité est largement améliorée.The present invention aims to improve the latter transducer, and relates to an electroacoustic transducer whose efficiency is greatly improved.

A cette fin, selon l'invention, le transducteur du type décrit dans le document US-A-3 022 385, est caractérisé en en que ledit élément émetteur d'ions est agencé entre lesdites deux premières électrodes, et en ce que ladite seconde électrode est agencée au voisinage dudit élément émetteur d'ions de façon que ledit flux d'ions forme une membrane vibrante entre ledit élément émetteur d'ions et ladite seconde électrode.To this end, according to the invention, the transducer of the type described in document US-A-3 022 385, is characterized in that said ion-emitting element is arranged between said two first electrodes, and in that said second electrode is arranged in the vicinity of said ion emitting element so that said ion flow forms a vibrating membrane between said ion emitting element and said second electrode.

Ainsi, ledit flux d'ions joue le rôle d'une membrane vibrante immatérielle. En effet, le fluide ionisé, créé entre l'élément émetteur d'ions et la seconde électrode, est attiré par les premières électrodes au rythme de la modulation, en engendrant ainsi des pressions acoustiques dans l'air.Thus, said ion flow plays the role of an immaterial vibrating membrane. Indeed, the ionized fluid, created between the ion-emitting element and the second electrode, is attracted by the first electrodes at the rate of the modulation, thereby generating acoustic pressures in the air.

Dans le cas où ledit élément émetteur d'ions est un fil, avantageusement, deuxdites secondes électrodes parallèles sont prévues de part et d'autre dudit fil respectivement, lesdites secondes électrodes étant orthogonales auxdites premières électrodes. De préférence, lesdites secondes électrodes sont disposées à des distances égales dudit fil. Ce dernier, notamment en acier inoxydable ou en platine, peut présenter un diamètre compris entre 20 et 50 micromètres.In the case where said ion emitting element is a wire, advantageously, two said second parallel electrodes are provided on either side of said wire respectively, said second electrodes being orthogonal to said first electrodes. Preferably, said second electrodes are arranged at equal distances from said wire. The latter, in particular in stainless steel or platinum, can have a diameter of between 20 and 50 micrometers.

Dans le cas où ledit élément émetteur d'ions est une pointe, soit une pluralité de secondes électrodes ponctuelles sont disposées en éventail autour de ladite pointe, soit ladite seconde électrode présente approximativement la forme d'un fer à cheval entourant ladite pointe.In the case where said ion emitting element is a point, either a plurality of second point electrodes are arranged in a fan around said point, or said second electrode has approximately the shape of a horseshoe surrounding said point.

Selon une autre caractéristique de l'invention, lesdites premières électrodes sont disposées à des distances égales dudit élément émetteur d'ions.According to another characteristic of the invention, said first electrodes are arranged at equal distances from said ion emitting element.

Avantageusement, lesdites premières électrodes sont des grilles en matière textile rigide recouverte de carbone.Advantageously, said first electrodes are grids of rigid textile material covered with carbon.

De préférence, ledit élément émetteur d'ions est porté à un potentiel négatif de l'ordre de -4,5 kV au moins.Preferably, said ion-emitting element is brought to a negative potential of the order of at least -4.5 kV.

Les figures du dessin annexé feront bien comprendre comment l'invention peut être réalisée. Sur ces figures, des références identiques désignent des éléments semblables.The figures of the appended drawing will make it clear how the invention can be implemented. In these figures, identical references designate similar elements.

Les figures 1 et 2 illustrent un premier exemple de réalisation du transducteur électroacoustique de l'invention, dans lequel l'élément émetteur d'ions est un fil.Figures 1 and 2 illustrate a first embodiment of the electroacoustic transducer of the invention, in which the ion emitting element is a wire.

Les figures 3 et 4, et 5 et 6 illustrent, respectivement, deux variantes d'un second exemple de réalisation du transducteur électroacoustique de l'invention, dans lequel l'élément émetteur d'ions est une pointe.Figures 3 and 4, and 5 and 6 illustrate, respectively, two variants of a second embodiment of the electroacoustic transducer of the invention, in which the ion emitting element is a tip.

En se référant aux figures 1 et 2, le transducteur électroacoustique 1 comporte un fil 2, relié à une source de haute tension 3, susceptible d'émettre des ions lorsqu'il est porté à un potentiel électrique suffisamment élevé, par exemple un potentiel négatif de l'ordre de - 4,5 kV au moins, potentiel négatif ne donnant pas de bruits de décharge. Le fil 2 est agencé entre deux premières électrodes 4,5, parallèles l'une à l'autre, reliées à un modulateur 6 par l'intermédiaire d'un transformateur 7. Un champ électrique modulé peut ainsi être créé entre les deux électrodes 4,5, pour agir sur lesdits ions. Les électrodes 4,5 sont avantageusement réalisées sous forme de grilles en matière textile rigide recouverte de carbone. De ce fait, la formation d'arcs en présence de fortes modulations est rarissime, et ceux-ci ne sont pas entretenus comme ils le seraient avec des grilles métalliques.Referring to Figures 1 and 2, the electroacoustic transducer 1 comprises a wire 2, connected to a high voltage source 3, capable of emitting ions when it is brought to a sufficiently high electrical potential, for example a negative potential of the order of - 4.5 kV at least, negative potential giving no discharge noises. The wire 2 is arranged between two first electrodes 4,5, parallel to each other, connected to a modulator 6 via a transformer 7. A modulated electric field can thus be created between the two electrodes 4 , 5, to act on said ions. The electrodes 4,5 are advantageously produced in the form of grids of rigid textile material covered with carbon. As a result, the formation of arcs in the presence of strong modulations is extremely rare, and these are not maintained as they would be with metal grids.

Par ailleurs, deux secondes électrodes 8,9, parallèles l'une à l'autre, reliées à la masse sont disposées de part et d'autre dudit fil 2 respectivement, lesdites secondes électrodes 8,9 étant orthogonales auxdites premières électrodes 4,5. Il convient de noter, de plus, que les premières 4,5 et secondes 8,9 électrodes sont avantageusement disposées à des distances égales du fil, respectivement, de façon à éviter de créer un vent ionique lors de l'application de la tension négative de polarisation.Furthermore, two second electrodes 8,9, parallel to one another, connected to ground are disposed on either side of said wire 2 respectively, said second electrodes 8,9 being orthogonal to said first electrodes 4,5 . It should be noted, moreover, that the first 4.5 and second 8.9 electrodes are advantageously arranged at equal distances from the wire, respectively, so as to avoid creating an ionic wind during the application of the negative voltage. of polarization.

Le champ électrique modulé créé entre les premières électrodes 4,5 agit ainsi sur le flux d'ions 10, engendré entre le fil 2 et les secondes électrodes 8,9, jouant le rôle d'une membrane vibrante immatérielle. En d'autres termes, le fluide ionisé créé entre le fil 2 et les électrodes de masse 8,9 est attiré par les grilles 4,5 au rythme de la modulation, en produisant ainsi des pressions acoustiques dans l'air.The modulated electric field created between the first electrodes 4,5 thus acts on the ion flow 10, generated between the wire 2 and the second electrodes 8,9, playing the role of a non-material vibrating membrane. In other words, the ionized fluid created between the wire 2 and the ground electrodes 8, 9 is attracted by the grids 4.5 at the rate of the modulation, thereby producing acoustic pressures in the air.

Dans les deux variantes de l'exemple de réalisation du transducteur électroacoustique 1 illustrées par les figures 3 à 6, le fil émetteur d'ions est remplacé par une pointe.In the two variants of the embodiment of the electroacoustic transducer 1 illustrated by FIGS. 3 to 6, the ion-emitting wire is replaced by a tip.

La pointe 11 est agencée dans une bague de support 12, de sorte que le bout 11a de celle-ci se trouve au centre de ladite bague 12. Comme dans le cas précédent, la pointe 11 reliée à une source de haute tension 13, est susceptible d'émettre des ions lorsqu'elle est portée à un potentiel électrique suffisamment élevé, par exemple un potentiel négatif de l'ordre de -4,5 kV. Egalement la pointe 11, et en particulier le bout 11a de celle-ci, est agencée entre deux premières électrodes 14,15, parallèles l'une à l'autre, reliées à un modulateur 16 par l'intermédiaire d'un transformateur 17. Ces électrodes 14,15 sont avantageusement du même type que les électrodes 4,5 décrites précédemment.The tip 11 is arranged in a support ring 12, so that the tip 11a thereof is located in the center of said ring 12. As in the previous case, the tip 11 connected to a high voltage source 13, is capable of emitting ions when it is brought to a sufficiently high electrical potential, for example a negative potential of the order of -4.5 kV. Also the tip 11, and in particular the tip 11a thereof, is arranged between two first electrodes 14,15, parallel to each other, connected to a modulator 16 by means of a transformer 17. These electrodes 14,15 are advantageously of the same type as the electrodes 4,5 described above.

Dans une première variante illustrée par les figures 3 et 4, une pluralité de secondes électrodes ponctuelles 18 (par exemple trois électrodes 18), reliées à la masse, sont disposées en éventail autour du bout 11a de la pointe 11. Dans la seconde variante illustrée par les figures 5 et 6, une seconde électrode unique 19, reliée à la masse, présentant approximativement la forme d'un fer à cheval entoure le bout 11a de la pointe 11.In a first variant illustrated by FIGS. 3 and 4, a plurality of second point electrodes 18 (for example three electrodes 18), connected to ground, are arranged in a fan around the end 11a of the tip 11. In the second illustrated variant by FIGS. 5 and 6, a second single electrode 19, connected to ground, having approximately the shape of a horseshoe surrounds the tip 11a of the tip 11.

Comme dans le cas précédent, le champ électrique modulé créé entre les premières électrodes 14,15 et la pointe 11 agit sur le flux d'ions 20, engendré entre la pointe 2 et la ou les secondes électrodes 18,19, jouant le rôle de membrane vibrante immatérielle.As in the previous case, the modulated electric field created between the first electrodes 14,15 and the tip 11 acts on the ion flow 20, generated between the tip 2 and the second electrode (s) 18,19, playing the role of immaterial vibrating membrane.

Claims (10)

  1. Electroacoustic transducer, of the type comprising at least one element (2, 11) which is capable of emitting ions when it is taken to a sufficiently high electrical potential, the said element (2, 11) being arranged in the vicinity of two first electrodes (4, 5; 14, 15), parallel to each other, linked to a modulator, and between which a modulated electric field is capable of being created, and at least one second electrode (8, 9; 18; 19) having an electrical potential such that an ion flux (10, 20) is created between the said ion emitter (2, 11) and the said second electrode (8, 9; 18; 19), in such a way that the said modulated electric field acts on the said ion flux (10, 20), characterised in that the said ion emitter element (2, 11) is arranged between the said two first electrodes (4, 5; 14, 15), and in that the said second electrode (8, 9; 18; 19) is arranged in the vicinity of the said ion emitter element (2, 11) in such a way that the said ion flux (10, 20) forms a virtual vibrating membrane between the said ion emitter element (2, 11) and the said second electrode (8, 9; 18; 19).
  2. Electroacoustic transducer according to Claim 1, in which the said ion emitter element is a wire, characterised in that two said second, parallel electrodes (8, 9) are provided on either side of the said wire (2) respectively, the said second electrodes (8, 9) being orthogonal to the said first electrodes (4, 5).
  3. Electroacoustic transducer according to Claim 2, characterised in that the said second electrodes (8, 9) are arranged at equal distances from the said wire (2).
  4. Electroacoustic transducer according to Claim 2 or Claim 3, characterised in that the said wire (2), preferably made of stainless steel or platinum, exhibits a diameter lying between 20 and 50 micrometres.
  5. Electroacoustic transducer according to Claim 1, in which the said ion emitter element is a pin, characterised in that a plurality of second point electrodes (18) are arranged in a fan around the said pin (11).
  6. Electroacoustic transducer according to Claim 1, in which the said ion emitter element is a pin, characterised in that the said second electrode (19) exhibits approximately the shape of a horseshoe surrounding the said pin (11).
  7. Electroacoustic transducer according to any one of Claims 1 to 6, characterised in that the said first electrodes (4, 5; 14, 15) are arranged at equal distances from the said ion emitter element (2, 11).
  8. Electroacoustic transducer according to any one of Claims 1 to 7, characterised in that the said first electrodes (4, 5; 14, 15) are grids made of rigid textile material covered with carbon.
  9. Electroacoustic transducer according to any one of Claims 1 to 8, characterised in that the said ion emitter element (2, 11) is taken to a negative potential of the order of at least -4.5 kV.
  10. Acoustic enclosure, characterised in that it comprises at least one electroacoustic transducer according to any one of Claims 1 to 9.
EP89402966A 1988-11-10 1989-10-26 Electroacoustic transducer Expired - Lifetime EP0370846B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT89402966T ATE92701T1 (en) 1988-11-10 1989-10-26 ELECTROACOUSTIC TRANSDUCER.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8814696 1988-11-10
FR8814696A FR2638930B1 (en) 1988-11-10 1988-11-10 ELECTROACOUSTIC TRANSDUCER

Publications (2)

Publication Number Publication Date
EP0370846A1 EP0370846A1 (en) 1990-05-30
EP0370846B1 true EP0370846B1 (en) 1993-08-04

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Application Number Title Priority Date Filing Date
EP89402966A Expired - Lifetime EP0370846B1 (en) 1988-11-10 1989-10-26 Electroacoustic transducer

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EP (1) EP0370846B1 (en)
JP (1) JPH02174398A (en)
AT (1) ATE92701T1 (en)
AU (1) AU621948B2 (en)
CA (1) CA2002803A1 (en)
DE (1) DE68908100D1 (en)
FR (1) FR2638930B1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2685156A1 (en) * 1991-12-16 1993-06-18 Languedoc Acieries Haut Electroacoustic transducer, and acoustic enclosure including at least one such transducer
GB2312590B (en) * 1996-04-26 2000-05-17 Keith Duncan Howard Loudspeaker
FR2782595B1 (en) * 1998-08-18 2001-04-20 Marc Charbonneaux ELECTRIC ACOUSTIC TRANSDUCER HARMONIC AMPLIFIER
WO2012002924A1 (en) * 2010-06-30 2012-01-05 Chijov Maksim Viktorovich Method for generating acoustic waves and device for carrying out said method
CN110430515B (en) * 2019-08-23 2021-03-23 苏州锐丰建声灯光音响器材工程安装有限公司 Improved plasma loudspeaker

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2793324A (en) * 1956-08-28 1957-05-21 Michael N Halus Ionic triode speaker
US3022385A (en) * 1958-08-25 1962-02-20 Takis N Panay Sound producer
FR1427695A (en) * 1963-09-25 1966-02-11 Electrokinetics Inc Electrohydrodynamic sound device
FR2246151A1 (en) * 1973-08-24 1975-04-25 Doucet Henri Guide-band plasma-type loudspeaker - modulates gas ionised by radioactive surface with audio-frequencies to radiate sound
FR2506551A1 (en) * 1981-05-21 1982-11-26 Bondar Henri METHOD AND DEVICE FOR TRANSFORMING A PERIODIC BF ELECTRICAL VOLTAGE INTO ACOUSTIC WAVES OR REVERSE
FR2559636A1 (en) * 1984-02-15 1985-08-16 Valois Distribution Electroacoustic transducer with ion emission.
FR2581497B1 (en) * 1985-05-02 1987-10-09 Valois Distribution ELECTRO-ACOUSTIC TRANSDUCER WITH ION EMISSION

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Publication number Publication date
CA2002803A1 (en) 1990-05-10
FR2638930B1 (en) 1991-05-31
AU621948B2 (en) 1992-03-26
EP0370846A1 (en) 1990-05-30
ATE92701T1 (en) 1993-08-15
AU4431689A (en) 1990-05-17
FR2638930A1 (en) 1990-05-11
DE68908100D1 (en) 1993-09-09
JPH02174398A (en) 1990-07-05

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