EP0684084A1 - Verfahren und Wandler zum Ausstrahlen von Breitband- und Niederfrequenz-Schallwellen in unbegrensden Tauchtiefe - Google Patents
Verfahren und Wandler zum Ausstrahlen von Breitband- und Niederfrequenz-Schallwellen in unbegrensden Tauchtiefe Download PDFInfo
- Publication number
- EP0684084A1 EP0684084A1 EP95401229A EP95401229A EP0684084A1 EP 0684084 A1 EP0684084 A1 EP 0684084A1 EP 95401229 A EP95401229 A EP 95401229A EP 95401229 A EP95401229 A EP 95401229A EP 0684084 A1 EP0684084 A1 EP 0684084A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- liquid
- cavity
- housing
- transducer
- bladder
- 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
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
- B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
- B06B1/0611—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements in a pile
- B06B1/0618—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements in a pile of piezo- and non-piezoelectric elements, e.g. 'Tonpilz'
Definitions
- the present invention relates to a method and transducer for emitting wideband and low frequency acoustic waves in unlimited immersion depth.
- the technical sector of the invention is that of the manufacture of electro-acoustic transducers for the emission of acoustic waves in a liquid.
- the main application of the invention is the possibility of emitting acoustic waves at low frequencies, at very great depth and in a fairly wide frequency band.
- Immersible electro-acoustic transducers and in particular piezoelectric transducers, are known, some of which for which the present invention is preferably intended, but without being limited thereto, comprise a rigid cylindrical housing, hollow and open at its two axial ends, and inside which are arranged coaxially with the latter, two identical electro-acoustic motors, placed on either side of a central counter-mass, and whose opposite ends are surrounded by a flag. Said electro-acoustic motors can be produced by two stacks of aligned piezoelectric plates.
- the external faces of the two flags are located in the plane of the axial ends of the housing, so that they are in contact with the liquid, in which the housing is immersed, and the external perimeter of these flags comes as close as possible to the edge. open axial ends of said housing.
- these external faces emit acoustic waves into the liquid when the electro-acoustic motors are electronically excited: these transducers are used in particular to emit low-frequency acoustic waves in water in a determined direction.
- a second category of solution is not wanting to resist external pressure, by admitting it directly inside the housing, without a complex system, such as in the patent applications FR. 2,671,928 and 2,674,927 published on July 24, 1992 and deposited by the French State, General Delegation for the Armament, and entitled "directive electroacoustic transducers”: these comprise a case with cylindrical walls and a bottom, separated by slots closed by a deformable membrane, and closed by a flexible diagram which delimits a cavity filled with oil; this allows a transmission and a balance of pressure inside, but also due to the transparency of the flexible membranes to acoustic waves, the retransmission in the ambient environment of the rear waves which creates a resonance peak of high frequencies, with a drop in emission level between this and that of the base frequencies, reducing the power, and therefore the total range of the emission.
- a third category of solution makes it possible to overcome both the mechanical and / or pneumatic problems of the first solution and the corresponding narrow band of frequency, as well as the problems of drops in emission level and shift towards the highs. frequencies of the second solution: this category is described in the patent application FR.
- a fourth category of solution making it possible not to imitate the depth while keeping a fairly wide and low frequency band, and without complexity of construction, has been developed with a housing made of material resistant to elastic pressure, and comprising an opening, the dimensions of which are determined so that by coupling the elasticity of the housing with the mass of the liquid located in this opening, the Helmholtz frequency of the housing cavity is close to the fundamental frequency of the vibrations of the assembly of the transducer:
- this category of solution has been especially developed for transducers such as those described in the introduction to this description, comprising a cylindrical, rigid and hollow housing open at its two axial ends, and inside which are arranged coaxially with this, two identical electroacoustic motors, placed on either side of a counter central mass, and whose opposite ends are surrounded by a flag.
- the problem is therefore to be able to produce low frequency acoustic transducers in a liquid, without limiting the depth, without weighing down or increasing the volume and / or the complexity of production of these transducers, and with a frequency bandwidth of fairly broad emission, without significant drop in level attenuation over the entire width of this band.
- At least one bladder is filled with a liquid that is more compressible than the liquid; at least one opening is made in said housing allows both the passage of said bladder thus filled; sliding said bladder into said cavity through said opening, so that all or at least part of the volume of said cavity is occupied by at least said bladder.
- transducer for emitting low frequency acoustic waves in a liquid as defined above, or comprising at least one electroacoustic motor vibrating any wall emitting said waves, and a hollow housing enclosing said motor, and delimiting, inter alia, with said vibrating wall, a cavity, which transducer comprises at least one opening making said cavity communicate with the ambient medium, at least one flexible bladder occupying all or at least part of the whole of the volume of said cavity, which bladder being filled with a liquid more compressible than said liquid.
- the compressibility of the liquid is less than 10 9 N / m 2
- the viscosity of the liquid is at most equal to that of water, which has the value 10- 6 m 2 / second: preferably, the viscosity of the liquid is less than 6.5 10- m2 / second.
- a liquid corresponding to the above characteristics is preferably chosen as being a fully fluorinated organic compound, of the C8F18 type, obtained by reaction of C8H18 + 18 HF: its density
- Silicate oil can also be used, the density of which is greater than 920 kg / m 3 , and the speed of propagation of the sound in this oil is greater than 1010 m / second, corresponding to a compressibility module. greater than 0.954 x 10 9 N / m 2 .
- such a method and transducer according to the invention allow in particular to combine the advantages mentioned above in the third and fourth categories of solutions analyzed in the introduction, namely: that of a cavity filled with ambient liquid, and in which closed elastic tubes are placed, making it possible to obtain two resonance peaks determining a fairly wide range of frequency bands, and without loss or attenuation of more than 5 dB between these two peaks; and the solution of an opening of determined dimensions so that the Helmholtz frequency of the cavity is close to that fundamental of the vibrations of the mechanical assembly, which makes it possible to descend in frequency, while resisting unlimited pressures.
- the characteristics of the present invention are applicable to any type of transducers, having a cavity in communication with the ambient medium, such as those described above and taken as examples in the figure below, but also in transducers of the flextensional type: may for example cite for this type of transducer the patent GN-8823245 of JROSWIN which, in the cavity filled with water of a conventional flextensional transducer, adds a Helmholtz resonator; Compliant tubes can be inserted to increase compliance and therefore decrease in frequency.
- the interest of the present invention is maximum whenever it is desired to reduce the loss of efficiency and attenuation of frequencies between two resonance peaks, one of which is linked to the mechanical resonance of the assembly, and the other than that of a cavity.
- the compressible liquid, located, in the present invention, therein, has not at all the same function as those used in the current prior art, which is in fact either a transmission and compensation liquid only for the external pressure, or a coolant, and the choice, arrangement, and criteria had not been determined to date to solve the problem posed in the present invention.
- transducers according to the present invention is to be able to be used in the context of acoustic ocean tomography, for which it is necessary to be able to immerse the transducers up to 2,000 meters of immersion on the one hand, and on the other hand, being able to transmit in fairly wide frequency bands, and at the lowest possible frequencies, to have the farthest propagation of the waves: a publication of the review "Pour la Science" No.
- the single figure is a sectional view of a particular type of transducer, equipped with the characteristic elements of the invention.
- the transducer as shown in section in this figure, comprises in a known manner, two electroacoustic motors 1, aligned along an axis xx ', placed on either side of a central counter mass 2, and coaxially with the inside of a cylindrical housing 5, covering all of said motors 1 up to the flag 3 at the end thereof; the cavity 7 thus defined by the rear of said pavilions and the housing is in communication with the external immersion liquid 4, thanks to openings 6 made in this housing 5.
- Said electroacoustic motors 1 can be of the piezoelectric type, but also magnetostrictive cylinders surrounded by an excitation coil.
- Such dual motor electroacoustic transducers are also called double Tonpilz.
- said electroacoustic motors 1 and the intermediate counterweight 2 are shown assembled assembled, by means of different connecting parts 11, themselves connected to different fixing parts 12, connecting said electroacoustic motor or housing 5, by any means fixing means, and allowing freedom of movement of the end pavilions 3 relative to said housing, but determining an internal cavity 7 almost closed between the respective edges 13 of said pavilions and said housing.
- the power supply of said electroacoustic motors 1 is supplied by any power cable 10, fixed to said connecting pieces 11 by an electrical connector 14.
- the main characteristic of the method of the present invention and of the transducer according to it, is that it comprises at least one flexible bladder 8, occupying at least a part if not the whole of the entire volume of said cavity 7, and filled with a liquid 9 which is more compressible than the ambient liquid 4.
- the liquid 9 occupying the volumes delimited by the skin of said bladders 8, must fill at best and preferably practically the entire cavity, since its volume must in fact be greater than that of the compliant tubes such as those described in the application for FR patent. 2.665.998 of 05 May 1988, so as to have compressibility characteristics equivalent to that of said tubes as used to date in this type of transducer; in fact, the drop in frequency emission level in the range defined between the two peaks considered above, is precisely related to the elasticity of the volume of this liquid included in the cavity, and whose role is also that of the compliant tubes of the patent cited above.
- the compressibility of said liquid must in fact be less than 10 9 N / m 2 , defined by the product of its density f with the square of the speed of propagation of sound in this liquid C f .
- said opening 6 is such that its dimensions are determined so that by coupling the elasticity of the housing 5 with the mass of the liquid located in this opening 6, the Helmholtz frequency of the cavity 7 of the housing is close to the fundamental frequency of the vibrations of the whole transducer.
- a transducer comprises two electroacoustic motors 1 aligned on an axis xx 'placed on either side of a central counterweight 2 and coaxially inside said housing 5 cylindrical and hollow, covering all of said motors 1 up to the vibrating walls 3 forming an end flag thereof, which opening 6 is made in said housing in the vicinity of its median plane.
- said edges of said opening 6 are each associated with a crown of material resistant to the pressure and forming an integral part of the housing of which they are integral; said crown is not shown in the figure.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Transducers For Ultrasonic Waves (AREA)
- Piezo-Electric Transducers For Audible Bands (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9406439 | 1994-05-27 | ||
| FR9406439A FR2720589B1 (fr) | 1994-05-27 | 1994-05-27 | Procédé et transducteur pour émettre des ondes acoustiques à larges bandes et basses fréquences en profondeur d'immersion illimitée. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0684084A1 true EP0684084A1 (de) | 1995-11-29 |
| EP0684084B1 EP0684084B1 (de) | 1998-11-25 |
Family
ID=9463568
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP95401229A Expired - Lifetime EP0684084B1 (de) | 1994-05-27 | 1995-05-26 | Verfahren und Wandler zum Ausstrahlen von Breitband- und Niederfrequenz-Schallwellen in unbegrenzter Tauchtiefe |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US5579287A (de) |
| EP (1) | EP0684084B1 (de) |
| CA (1) | CA2150297C (de) |
| DE (1) | DE69506169T2 (de) |
| DK (1) | DK0684084T3 (de) |
| ES (1) | ES2124507T3 (de) |
| FR (1) | FR2720589B1 (de) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2971112A1 (fr) * | 2011-02-01 | 2012-08-03 | Ixblue | Transducteur electro-acoustique basse frequence et procede de generation d'ondes acoustiques. |
| CN116532349A (zh) * | 2023-06-07 | 2023-08-04 | 中国科学院声学研究所 | 复合驱动的亥姆赫兹换能器 |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2818754B1 (fr) * | 2000-12-21 | 2004-06-18 | Inst Francais Du Petrole | Dispositif pour engendrer des ondes elastiques focalisees dans un milieu materiel tel que le sous-sol, et methode pour sa mise en oeuvre |
| EP1612728A3 (de) * | 2001-04-06 | 2008-06-11 | Océ Printing Systems GmbH | Verfahren, System und Computerprogramm zum Erstellen eines elektronischen Dokuments aus gerasterten Bilddaten |
| DE10345533A1 (de) * | 2003-09-30 | 2005-05-04 | Fraunhofer Ges Forschung | Ultraschallwandler zum Betrieb in einem unter erhöhtem Druck stehenden Medium |
| GB2508206B (en) * | 2012-11-23 | 2017-06-28 | Thales Holdings Uk Plc | A transducer for a locator beacon and an underwater locator beacon |
| US9995834B2 (en) * | 2013-05-07 | 2018-06-12 | Pgs Geophysical As | Variable mass load marine vibrator |
| US10488542B2 (en) | 2014-12-02 | 2019-11-26 | Pgs Geophysical As | Use of external driver to energize a seismic source |
| US20160202365A1 (en) * | 2015-01-08 | 2016-07-14 | Pgs Geophysical As | Compliance chamber with linear motor for marine acoustic vibrators |
| FR3042134B1 (fr) | 2015-10-09 | 2020-10-09 | Ixblue | Dispositif d'emission/reception acoustique sous-marine a large bande |
| US12345154B2 (en) | 2022-09-14 | 2025-07-01 | Saudi Arabian Oil Company | Untethered logging devices and related methods of logging a wellbore |
| US11913329B1 (en) | 2022-09-21 | 2024-02-27 | Saudi Arabian Oil Company | Untethered logging devices and related methods of logging a wellbore |
| CN117299517B (zh) * | 2023-09-22 | 2026-04-24 | 中国船舶集团有限公司第七一五研究所 | 一种深水溢流式弯曲圆盘换能器 |
| US12486762B2 (en) | 2024-01-11 | 2025-12-02 | Saudi Arabian Oil Company | Systems and methods for untethered wellbore investigation using modular autonomous device |
| US12644373B2 (en) | 2024-06-14 | 2026-06-02 | Saudi Arabian Oil Company | Systems and methods for multi-offset seismic profiling |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3274537A (en) * | 1963-10-17 | 1966-09-20 | William J Toulis | Flexural-extensional electro-mechanical transducer |
| FR2498867A1 (fr) * | 1981-01-27 | 1982-07-30 | Tech Radioelect Electro Fs | Transducteur electroacoustique de puissance concu pour les immersions a grande profondeur |
| FR2569326A1 (fr) * | 1984-08-16 | 1986-02-21 | France Etat Armement | Transducteurs piezo-electriques et antennes de sonar pouvant etre immerges a grande profondeur |
| EP0363032A2 (de) * | 1988-10-04 | 1990-04-11 | British Aerospace Public Limited Company | Flexeinsgespannter Wandler |
| EP0596763A1 (de) * | 1992-11-05 | 1994-05-11 | ETAT-FRANCAIS représenté par le DELEGUE GENERAL POUR L'ARMEMENT (DPAG) | Verfahren und Wandler zum Aussenden von niederfrequenten akustischen Wellen, welcher in einer Flüssigkeit unbeschränkt eingetaucht ist |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4875199A (en) * | 1986-09-09 | 1989-10-17 | Hutchins Roger W | Deep water transient sound generator |
| FR2665998B1 (fr) * | 1988-05-05 | 1993-10-29 | Etat Francais Delegue Armement | Procedes et transducteurs electro-acoustiques pour emettre des ondes acoustiques a basse frequence dans un liquide. |
| 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 |
| US4868799A (en) * | 1988-10-11 | 1989-09-19 | Frank Massa | Means for equalizing the internal pressure in an underwater transducer employing a vibratile piston to permit operation of the transducer at water depths in excess of a few hundred feet |
| 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. |
| US5291461A (en) * | 1990-11-28 | 1994-03-01 | Raytheon Company | Elastomer structure for transducers |
| FR2671928B1 (fr) * | 1991-01-22 | 1995-10-20 | France Etat Armement | Transducteurs electro-acoustiques directifs. |
| DE4111296A1 (de) * | 1991-04-08 | 1992-10-22 | Gkn Automotive Ag | Verstellvorrichtung fuer eine reibungskupplung |
-
1994
- 1994-05-27 FR FR9406439A patent/FR2720589B1/fr not_active Expired - Fee Related
-
1995
- 1995-05-26 ES ES95401229T patent/ES2124507T3/es not_active Expired - Lifetime
- 1995-05-26 CA CA002150297A patent/CA2150297C/fr not_active Expired - Fee Related
- 1995-05-26 DK DK95401229T patent/DK0684084T3/da active
- 1995-05-26 DE DE69506169T patent/DE69506169T2/de not_active Expired - Fee Related
- 1995-05-26 EP EP95401229A patent/EP0684084B1/de not_active Expired - Lifetime
- 1995-05-30 US US08/452,854 patent/US5579287A/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3274537A (en) * | 1963-10-17 | 1966-09-20 | William J Toulis | Flexural-extensional electro-mechanical transducer |
| FR2498867A1 (fr) * | 1981-01-27 | 1982-07-30 | Tech Radioelect Electro Fs | Transducteur electroacoustique de puissance concu pour les immersions a grande profondeur |
| FR2569326A1 (fr) * | 1984-08-16 | 1986-02-21 | France Etat Armement | Transducteurs piezo-electriques et antennes de sonar pouvant etre immerges a grande profondeur |
| EP0363032A2 (de) * | 1988-10-04 | 1990-04-11 | British Aerospace Public Limited Company | Flexeinsgespannter Wandler |
| EP0596763A1 (de) * | 1992-11-05 | 1994-05-11 | ETAT-FRANCAIS représenté par le DELEGUE GENERAL POUR L'ARMEMENT (DPAG) | Verfahren und Wandler zum Aussenden von niederfrequenten akustischen Wellen, welcher in einer Flüssigkeit unbeschränkt eingetaucht ist |
Non-Patent Citations (1)
| Title |
|---|
| Y. LE GALL: "Transducteur basse fréquence, grande immersion, large bande et à rendement élevé, pour l'océanographie acoustique", ONDE ELECTRIQUE, vol. 74, no. 5, PARIS FR, pages 22 - 28, XP000468469 * |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2971112A1 (fr) * | 2011-02-01 | 2012-08-03 | Ixblue | Transducteur electro-acoustique basse frequence et procede de generation d'ondes acoustiques. |
| WO2012104549A3 (fr) * | 2011-02-01 | 2013-01-24 | Ixblue | Transducteur electro-acoustique basse frequence et procede de generation d'ondes acoustiques |
| CN103492090A (zh) * | 2011-02-01 | 2014-01-01 | 埃艾克斯布鲁公司 | 低频电声换能器和产生声波的方法 |
| CN103492090B (zh) * | 2011-02-01 | 2016-06-01 | 埃艾克斯布鲁公司 | 低频电声换能器和产生声波的方法 |
| US9387514B2 (en) | 2011-02-01 | 2016-07-12 | Ixblue | Low frequency electro acoustic transducer and method of generating acoustic waves |
| EP2670536B1 (de) * | 2011-02-01 | 2021-07-28 | Ixblue | Elektroakustischer niederfrequenzwandler und verfahren zur erzeugung von schallwellen |
| CN116532349A (zh) * | 2023-06-07 | 2023-08-04 | 中国科学院声学研究所 | 复合驱动的亥姆赫兹换能器 |
| CN116532349B (zh) * | 2023-06-07 | 2024-01-30 | 中国科学院声学研究所 | 复合驱动的亥姆赫兹换能器 |
Also Published As
| Publication number | Publication date |
|---|---|
| DE69506169D1 (de) | 1999-01-07 |
| EP0684084B1 (de) | 1998-11-25 |
| CA2150297C (fr) | 2006-12-19 |
| CA2150297A1 (fr) | 1995-11-28 |
| FR2720589B1 (fr) | 1996-07-05 |
| DE69506169T2 (de) | 1999-05-06 |
| DK0684084T3 (da) | 1999-08-09 |
| ES2124507T3 (es) | 1999-02-01 |
| FR2720589A1 (fr) | 1995-12-01 |
| US5579287A (en) | 1996-11-26 |
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