EP0657868A1 - Verfahren und Wandler zum Aussenden von sehr niederfrequenten akustischen Wellen mit grosser Leistung - Google Patents

Verfahren und Wandler zum Aussenden von sehr niederfrequenten akustischen Wellen mit grosser Leistung Download PDF

Info

Publication number
EP0657868A1
EP0657868A1 EP94402749A EP94402749A EP0657868A1 EP 0657868 A1 EP0657868 A1 EP 0657868A1 EP 94402749 A EP94402749 A EP 94402749A EP 94402749 A EP94402749 A EP 94402749A EP 0657868 A1 EP0657868 A1 EP 0657868A1
Authority
EP
European Patent Office
Prior art keywords
acoustic
motors
envelope
liquid
transducer according
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.)
Granted
Application number
EP94402749A
Other languages
English (en)
French (fr)
Other versions
EP0657868B1 (de
Inventor
Didier Le Saint Michel Boucher
Gilles Grosso
Alain Scarpitta
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.)
Direction General de lArmement DGA
Gouvernement de la Republique Francaise
Original Assignee
Delegation Generale pour lArmement
Gouvernement de la Republique Francaise
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 Delegation Generale pour lArmement, Gouvernement de la Republique Francaise filed Critical Delegation Generale pour lArmement
Publication of EP0657868A1 publication Critical patent/EP0657868A1/de
Application granted granted Critical
Publication of EP0657868B1 publication Critical patent/EP0657868B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K9/00—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
    • G10K9/12—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated
    • G10K9/121—Flextensional transducers

Definitions

  • the present invention relates to a method of transmitting very low frequency acoustic waves at high power, and corresponding transducers.
  • the technical sector of the invention is that of the production of electro-acoustic transducers for the emission of acoustic waves immersed in a liquid.
  • the main application of the invention is the possibility of emitting acoustic waves of very low frequencies and at high power, whatever the immersion depth.
  • flextensionals which comprise one or more electro-acoustic motors, generally piezoelectric motors, which are placed in the same plane at inside or in the peripheral crown of a flexible envelope or shell. It is this shell placed in contact with water, which then constitutes the emission surface of the acoustic waves.
  • transducers convert the oscillations of the hull generated in the plane where the electro-acoustic motors are located, and due to the effects of their expansion-compression, in oscillations perpendicular to this plane and therefore of flexion of the hull, hence their name flextensional transducers. They thus amplify the amplitude of the motor oscillations by a factor of 3 and even 4 and thus obtain very low frequencies.
  • the present invention relates more particularly, but not exclusively, to flextensional transducers of classes IV and V above.
  • All flextensional transducers have many advantages, for the emission of low and very low frequency waves, but they also have certain disadvantages, including that of requiring that the shells or envelopes are either closed and waterproof, or open and not waterproof, but then with particular devices which to date limit the effects of this non-sealing.
  • this shell can be closed and full of gas: it must then resist the immersion pressure; this however limits the use of such transducers to shallow depths, because if one wishes to increase the resistance of the shell to resist the pressure of great depths, one loses elasticity and therefore the possibility of emission; to avoid having to increase this resistance and keep this elasticity, specific devices were then developed and some were even the subject of various patents.
  • the emission is disturbed, especially in the range of very low frequencies and more, contrary to the objectives of the present application.
  • the emission level is lowered, which limits the possibility of transmitting at high power.
  • the objective of the present invention is indeed to be able to emit acoustic waves of very low frequencies into a liquid, without being hindered by the depth, without complicating the production of the transducers which for these frequency ranges are of the flextensional type and while allowing high power emissions.
  • the objective of the present invention is also achieved with a transducer of the same type known as that above, and in which its enclosure formed by part of said envelope has at least any opening allowing said liquid to penetrate the entire interior cavity delimited by said enclosure and a baffle made of alveolar material resistant to immersion pressure occupying most of the volume of the cavity, the external surface of which is at a constant distance from that of the vibrating envelope, and which is integral with the device assembly of electro-acoustic motors.
  • said cellular material has an acoustic impedance of less than 0.7 times that of water, for example a material of cellular plastic type based on P.V.C. (polyvinyl chloride) and with closed porosities.
  • a material of cellular plastic type based on P.V.C. polyvinyl chloride
  • the envelope in which the envelope is of shape and type ellipsoid, it consists of two discs placed opposite one another, convex, and connected at their periphery by at least one toroid-shaped part, such that these two discs are just supported and immobilized at their periphery, each in a groove of said toric piece.
  • the result is a new method of transmitting very low frequency and high power acoustic waves, as well as corresponding new transducers, allowing such emissions.
  • the total immersion of all the parts of the transducer and in particular of the cavity allows better cooling of the electro-acoustic motors by diffusion. calorific facilitated by the presence of the external fluid which is water, while in systems filled with air, this cooling is of course more difficult.
  • Figure 1 is a perspective view of a class IV flextensional transducer as it may exist to date.
  • Figure 2 is a sectional view of a class V flextensional transducer produced in accordance with the present invention.
  • the transducers shown are therefore by way of example for FIG. 1 a type IV transducer, and for FIG. 2 a type V transducer: they comprise, in a known manner. one or more electro-acoustic motors 1, placed along the same plane defined by the axes xx '/ yy', inside which relates to FIG. 1 and in the peripheral ring with regard to FIG. 2 of a flexible envelope 5, of which they are integral, at least at one of their ends by any assembly device, either in FIG. 1 for the parts or masses of connection 2, and in FIG.
  • said electro-acoustic motors 1 and their counter-masses 9 transmit their vibrations to said flexible envelope 5 which is in contact with said external liquid 4, constituting the surface for emitting acoustic waves; said flattened ellipsoid shape of said surface makes it possible to amplify the amplitude of the vibrations and to obtain a range of waves of very low frequencies.
  • the transducer of type IV shown, has a flexible envelope 5 of elongated cylinder shape, the cross section of which is in the shape of an ellipse, and the electro-acoustic motors 1 represented in number of three in this example, are parallel to each other. along an axis yy 'and their axes are placed in transverse planes perpendicular to the generatrices of the cylinder along the axis xx' of the envelope 5.
  • each motor is mechanically and acoustically coupled by the connecting pieces 2 with the cylindrical shell 5, but in other cases, in particular when it is a class II transducer according to the shape of the shell thereof, said motors 1 may be integral only at one of their ends, the other being able to bear on a central pillar acting as counterweight.
  • one of said end flanges 3 comprises at least one opening 6, the dimensions of which, according to the systems existing to date, associated with the characteristics of the casing 5, are determined so that by coupling the elasticity of this envelope with the mass of the liquid 4 located in said opening 6, the Helmholtz frequency of the cavity 7 is close to the fundamental frequency of the vibrations of the assembly formed by said electro-acoustic motors 1 and of any element associated with these, such as the connecting pieces 2.
  • such a type IV transducer according to FIG. 1 could be fitted according to the present invention with an internal baffle 15, as shown in the example in FIG. 2, and connected to the central part, for example electro-acoustic motors 1, since such a baffle must not be able to be driven by the external envelope 5 and can vibrate with it.
  • the latter comprises a motor ring 13 formed of a crown of several ceramic pillars or electro-acoustic motors 1 in number for example of eight, and associated with counter-masses 9, connected by various assembly screws 8 allowing, the continuity of the peripheral driving crown 13.
  • central rods 18 ensure the prestressing of the ceramic pillars 1 .
  • this crown motor element is not further specified in the context of the present description, since it is not an object of the invention, and there are already today various transducer systems using such a provision.
  • the casing 5 forming said vibrating shell is composed of two convex discs connected at their periphery by at least one part 10 in the form of a torus, so that these two convex discs 5 are just supported and immobilized at their periphery each in a groove 17 of the part 10.
  • the two convex discs can be turned both outwards, but also and possibly both inwards or one outwards and the other towards inside, but preferably, the orientation of the convexity of the two discs towards the outside will be chosen as shown in the figure.
  • Each of the grooves 17 is in fact carried by elements arranged in a crown, and constituting the parts 10, independent of each other for each of the two opposite and convex discs, and connected two by two, on either side of the plane in which are the acoustic motors 1, by any means 11 for adjusting relative distance; which crowns of parts 10 each have a conical surface 12, cooperating with a surface of the same shape, carried by another peripheral continuous outer ring 13, so that the action of bringing together elements of the part 10 by the means 11 , decreases the length of the circumference of the grooves 17 by pinching effect and provides prestressing of the discs 5.
  • the enclosure comprising the envelope 5, thus constituted comprises any opening, not shown in this section of figure, but being able to let said liquid 4 penetrate in all the interior cavity 7 delimited by the envelope, such as for example an opening between two motors 1 in the outer ring 13.
  • a baffle 15 of cellular material resistant to immersion pressure occupies most of the volume of the cavity 7, the external surface of which is at a constant distance 14 from that of the envelope 5, and which is integral with the device d assembly 8 of the electro-acoustic motors 1 in a ring 13.
  • This assembly can be carried out by elastic studs 16 spaced apart on the rear structure of the transducers 1, such as that formed by the supports and the counter-masses 9 over the entire periphery of this outer crown 13.
  • the elastic material constituting said studs 16 has elastic characteristics such that its radial speed of displacement in compression is less than ten times that of electro-acoustic motors.
  • said distance 14 separating the surfaces of the baffle 15 from the casing 5 and filled with liquid 4 is between 3 to 6 mm.
  • the acoustic and specific impedance again called characteristic impedance of the material which constitutes it, and defined by the product of its density rm and the speed Cm of wave propagation in the material, ie such that: (rm x Cm) of the material ⁇ 0.7 of (ro x Co) water.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Transducers For Ultrasonic Waves (AREA)
  • Piezo-Electric Transducers For Audible Bands (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
EP94402749A 1993-12-03 1994-12-01 Verfahren und Wandler zum Aussenden von sehr niederfrequenten akustischen Wellen mit grosser Leistung Expired - Lifetime EP0657868B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9314503A FR2713430B1 (fr) 1993-12-03 1993-12-03 Procédé d'émission d'ondes acoustiques très basses fréquences à forte puissance, et transducteurs correspondants.
FR9314503 1993-12-03

Publications (2)

Publication Number Publication Date
EP0657868A1 true EP0657868A1 (de) 1995-06-14
EP0657868B1 EP0657868B1 (de) 1999-08-11

Family

ID=9453523

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94402749A Expired - Lifetime EP0657868B1 (de) 1993-12-03 1994-12-01 Verfahren und Wandler zum Aussenden von sehr niederfrequenten akustischen Wellen mit grosser Leistung

Country Status (7)

Country Link
US (1) US5469406A (de)
EP (1) EP0657868B1 (de)
CA (1) CA2137187C (de)
DE (1) DE69420019T2 (de)
DK (1) DK0657868T3 (de)
ES (1) ES2135552T3 (de)
FR (1) FR2713430B1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0716407A3 (de) * 1994-12-10 1996-07-17 Stn Atlas Elektronik Gmbh

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7081699B2 (en) * 2003-03-31 2006-07-25 The Penn State Research Foundation Thermoacoustic piezoelectric generator
EP4094251B1 (de) 2020-01-21 2025-12-17 ADBM Corp. Gleichzeitiges dämpfen hoher frequenzen und verstärken niedriger frequenzen von unterwassergeräuschen

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0363032A2 (de) * 1988-10-04 1990-04-11 British Aerospace Public Limited Company Flexeinsgespannter Wandler
EP0421613A2 (de) * 1989-10-06 1991-04-10 British Aerospace Public Limited Company Schallerzeugender Wandler

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4135142A (en) * 1977-08-08 1979-01-16 The United States Of America As Represented By The Secretary Of The Navy Non-linear acoustic transducer
CA1171950A (en) * 1981-12-22 1984-07-31 Garfield W. Mcmahon Underwater transducer with depth compensation
US4853905A (en) * 1988-02-05 1989-08-01 Conoco Inc. Seal for marine seismic source
FR2634292B1 (fr) * 1988-07-15 1990-10-19 Grosso Gilles Procede et dispositifs pour maintenir le gaz contenu dans une enceinte immergee en equilibre de pression avec l'exterieur
US5223570A (en) * 1990-02-07 1993-06-29 Basf Corporation Method for the preparation of graft polymer dispersions having broad particle size distribution without wildly fluctuating viscosities
FR2665814B1 (fr) * 1990-08-10 1993-06-11 Thomson Csf Transducteur electroacoustique destine a etre immerge et comportant un systeme de compensation automatique de la pression d'immersion.
FR2671927B1 (fr) * 1991-01-22 1995-10-06 France Etat Armement Transducteurs electro-acoustiques directifs et procedes et dispositifs de fabrication.
US5268879A (en) * 1991-12-03 1993-12-07 Raytheon Company Electro-acostic transducers
US5224074A (en) * 1992-07-08 1993-06-29 The United States Of America As Represented By The Secretary Of The Navy Sonobuoy for forming virtual vertical sensing arrays

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0363032A2 (de) * 1988-10-04 1990-04-11 British Aerospace Public Limited Company Flexeinsgespannter Wandler
EP0421613A2 (de) * 1989-10-06 1991-04-10 British Aerospace Public Limited Company Schallerzeugender Wandler

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0716407A3 (de) * 1994-12-10 1996-07-17 Stn Atlas Elektronik Gmbh

Also Published As

Publication number Publication date
EP0657868B1 (de) 1999-08-11
FR2713430A1 (fr) 1995-06-09
US5469406A (en) 1995-11-21
CA2137187C (fr) 2003-10-21
CA2137187A1 (fr) 1995-06-04
DE69420019D1 (de) 1999-09-16
ES2135552T3 (es) 1999-11-01
DE69420019T2 (de) 1999-12-09
FR2713430B1 (fr) 1996-03-08
DK0657868T3 (da) 2000-03-06

Similar Documents

Publication Publication Date Title
EP2670536B1 (de) Elektroakustischer niederfrequenzwandler und verfahren zur erzeugung von schallwellen
EP2707779B1 (de) Uhr mit akustischem mechanismus
EP0684084B1 (de) Verfahren und Wandler zum Ausstrahlen von Breitband- und Niederfrequenz-Schallwellen in unbegrenzter Tauchtiefe
EP0002161A2 (de) Piezoelektrischer Übertrager und Verfahren zu seiner Herstellung
CH667356A5 (fr) Transducteur de vibration cylindrique du type a cintrage.
EP2858760A2 (de) Vorrichtung und verfahren zum fokussieren von impulsen
FR2557704A1 (fr) Source sismique marine
EP0728535B1 (de) Verfahren und Vorrichtung zur Verminderung der Resonanzfrequenz von Hohlräumen von Unterwasserwandlern
CA2137187C (fr) Procede d'emission d'ondes acoustiques tres basses frequences a forte puissance, et transducteurs correspondants
CH691335A5 (fr) Appareil susceptible d'être immergé et comprenant un transducteur sonore.
EP3677051B1 (de) Wasserschallgehäuse
FR2609337A1 (fr) Transducteur electroacoustique a decharges electriques disruptives pour analyse de sondages
CH710166A2 (fr) Agencement à membranes de rayonnement acoustique pour une montre musicale ou à sonnerie.
EP0656232A1 (de) Verfahren zum Hochleistungsemission von akustischen Wellen und damit übereinstimmende Wandlerhorne
CA2109466C (fr) Procede et transducteurs pour emettre des ondes acoustiques basse frequence dans un liquide en immersion illimitee
EP0114764B1 (de) Vorrichtung zur Reflexion von akustischen Wellen
FR2697710A1 (fr) Procédé et transducteur pour émettre des ondes acoustiques de très basses fréquences, dans un liquide en immersion illimitée.
EP0881001B1 (de) Elektrodynamischer Wandler für Unterwasser-Akustik
CA2109465C (fr) Dispositif d'etancheite de moteurs electro-acoustiques
EP0728534B1 (de) Verfahren und in einer Flussigkeit versekter Handler mit leichten Strahler zum Aussenden von niederfrequenten akustischen Wellen
FR2664782A1 (fr) Enceinte acoustique omnidirectionnelle.
CA2038737C (fr) Procedes et transducteurs electro-acoustiques pour emettre des ondes acoustiques a basse frequence dans un liquide
EP0728533A1 (de) Verfahren und Wandler zum Aussenden von akustischen Wellen in einer Flüssigkeit mit einer betonten Richtcharakteristik bei Niederfrequenzen
FR2664868A1 (fr) Revetement anechouide, en particulier pour coques de navires et de sous-marins.
EP2700247A1 (de) Vorrichtung zum aussenden von schallwellen

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19941227

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE DK ES GB IT NL SE

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

17Q First examination report despatched

Effective date: 19981209

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE DK ES GB IT NL SE

ITF It: translation for a ep patent filed
GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19990812

REF Corresponds to:

Ref document number: 69420019

Country of ref document: DE

Date of ref document: 19990916

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2135552

Country of ref document: ES

Kind code of ref document: T3

REG Reference to a national code

Ref country code: DK

Ref legal event code: T3

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20031031

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20031203

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20031230

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 20031231

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20040216

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DK

Payment date: 20041026

Year of fee payment: 11

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20041201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20041202

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20041202

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050701

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050701

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20041201

EUG Se: european patent has lapsed
NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20050701

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20051201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DK

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060102

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20041202

REG Reference to a national code

Ref country code: DK

Ref legal event code: EBP