US3199071A - Electroacoustic transducer construction suitable for operation in deep water - Google Patents

Electroacoustic transducer construction suitable for operation in deep water Download PDF

Info

Publication number
US3199071A
US3199071A US104420A US10442061A US3199071A US 3199071 A US3199071 A US 3199071A US 104420 A US104420 A US 104420A US 10442061 A US10442061 A US 10442061A US 3199071 A US3199071 A US 3199071A
Authority
US
United States
Prior art keywords
housing structure
enclosure
transducer
transducer means
sealed compartment
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
US104420A
Inventor
Massa Frank
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.)
Dynamics Corp of America
Original Assignee
Dynamics Corp of America
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 Dynamics Corp of America filed Critical Dynamics Corp of America
Priority to US104420A priority Critical patent/US3199071A/en
Application granted granted Critical
Publication of US3199071A publication Critical patent/US3199071A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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

  • an efficient electroacoustic transducer may be designed by employing piezoelectric materials for the conversion of electrical signals to mechanical vibrations.
  • a conventional design of such a transducer makes use of an assembly of piezoelectric expander plates, cut from ammonium dihydrogen phosphate or some other suitable piezoelectric material, which are operated at their natural resonant frequency as illustrated, for example, in U.S. Patent 2,521,642
  • Such a design is limited to relatively high frequency efiicient operation because the natural frequency of typical prior art crystal plate assemblies usually falls in the frequency range above 15,000 cycles per second. For lower frequencies, the plates of these prior art arrangements become impractically long in their dimensions and are subject to easy fracture when their assembly is attempted.
  • Another object of this invention is to provide a new and highly efiicient transducer construction which is pres sure equalized so that satisfactory operation can be achieved at great submerged depths under water.
  • FIGURE 1 is an end View showing the radiating surface of a new transducer embodying the invention
  • FIGURE 2 is an elevational View, partially in cross section, of a new transducer taken along the line 22 of FIGURE 1;
  • FIGURE 3 is a partial sectional view, similar to FIG- URE 2, showing another illustrative embodiment of active transducer element adapted for use in the transducer assembly of the present invention
  • FIGURE 4 is a perspective view of one of the crystal plates used in the embodiment of FIGURE 2 and arsaan Patented Aug. 3, 1965
  • FIGURE 5 is a perspective view of a split polarized ceramic cylinder which may be used as an alternative construction to the illustrative embodiment of FIGURE 3.
  • the reference numeral 10 identifies the radiating plane surface of a transducer assembly 12.
  • the radiating surface 10 is shown as a square, it will be appreciated that any other configuration, such as a circle or a polygon could be used.
  • the transducer assembly 12 is shown as comprising a vibratile plate member 14 mounted within the frame-like portion 16 of the housing structure and flexibly attached to the housing structure by the molded rubber member 13.
  • the rubber member 18 also is molded over the front radiating surface of the vibratile plate member 14 to provide a protective surface 2% for permitting improved long-life performance under water.
  • a cylindrical housing member 22 is secured as by brazing or any other suitable means, to the frame-like portion 16 to provide a completely sealed 7 housing to enclose the active transducer assembly.
  • the unique transducer structure comprises the vibratile plate member 14 and an assembly of piezoelectric crystal plates 24, such as 45 Z-cut ammonium dihydrogen phosphate, or 45 X-cut rochelle salt, or any other piezoelectric crystals which may be set into vibration by the application of an alternat ing voltage to a set of electrodes 26.
  • the crytsal plate assembly is firmly bonded to a prepared flat face 84 of the Vibratile plate member 14, and to a similarly prepared flat surface 86 of a weight 28 as shown in FIGURE 2.
  • a thin insulating Bakelite sheet (not shown) may be interposed and securely bonded between the ends of the crystal plates 24 and the surfaces of the adjoining plate 14 j and weight 28, if desired.
  • the purpose of providing the weight member 28 to load the crystal structure is to resonate the vibrating crystals at a lower frequency than would be possible were the loading weight omitted.
  • the crystal vibration amplitude may be held at a minimum with the corresponding advantageous reduction in stress, it is advantageous to make the vibratile plate 14 as light as possible, While making most of the load for frequency reduction reside in the non-radiating weight member 28.
  • the vibratile plate 14 therefor in one illustrative embodiment, is made of aluminum and, in cases where still further weight reduction is desired, the aluminum may be cast as a porous sponge-like mass which will preserve the rigidity of the plate, which is essential for satisfactory radiation of sound under water.
  • the vibratile plate 14 illustratedin FIGURE 2 is shown as a porous spongelike aluminum mass having inclusions of gas pockets 88 dispersed through its volume whereby its density is reduced.
  • the magnitude of the weight 23 is adjusted to result in a combined resonant frequency of the crystal plates 24, and the masses of the plate 14 and Weight 28 as desired for the operating frequency of the transducer.
  • Advan tageously a flexible spider member 343 is securely fastened to the center of the weight 28 as by the threaded fastener and spacer 34, and is also secured at its periphery to a ring member 36, which, in turn, is secured by any suitable means, such as brazing or welding, to the inner periphery of the housing structure 22.
  • the spider member 3% has transverse rigidity and keeps the weight 23 from being sheared off as at the bonded crystal surface during shock and vibration ml? "the transducer.
  • An end cap 38 is fastened to the housing 22, as by means of the radially dispose-d screws 4%.
  • an O-ring 42 provides a seal between end cap 38 and housing 22, as shown.
  • Insulated terminals 44 are provided to permit transfer of the electrical connections from the electrodes 26 of the crystal plates 24 to the external cable 46'.
  • a cable gland housing 43 is fastened .to the end cap 38 as by means of the screws 50 and and O-ring 52 provides the necessaryy underwater seal.
  • the cable 46 is sealed by the assembly of the compression rubber gland 54, the washer 56 and the nut 58.
  • nut 58 is tightened sufliciently to provide compression of the gland 54 to the surface of the cable
  • An orifice 64 is formed through the wall of the housing 22, as shown, to provide communication between the inner enclosure of the housing 22 and the reservoir enclosure 66 defined by the sealed rubber sleeve so and the outer surface of housing 22.
  • a suitable fluid such as castor oil, fills the inner enclosure of the trans :ducer assembly and the reservoir enclosure 66 of the as- :sembly. The oil may be poured into the transducer before the attachment of the end cap 38, and the rubber sleeve tit) may be pulled out from the housing as by means of a vacuum, to allow the oil to run into the formed reservoir enclosure 66.
  • a low acoustic impedance member 68 such as cork, is placed inside the transducer structure.
  • the members 68 serve as a pressure release during the vibration of the plate 14 during operation of the transducer and prevents other words, the compression of the air cells prevents the pressure from being built up in the fluid, and there- "fore, serves as a pressure release.
  • FIGURE 4 of the drawing An illustrative detailed showing of a 45 Z-cut ammonium di-hydrogen' phosphate crystal which is suitable for use in the inven- '-tion is shown in FIGURE 4 of the drawing.
  • a pair of metaltic electrode surfaces 26 are cemented to the opposite faces of the crystal plate 24 as shown. When potential surface.
  • the electrical conducting leads 70' and 72' connect the polarized ceramic cylinder 74 to the terminals of a suitable power cable so that electrical operating power may be supplied to the transducer.
  • the outer cylindrical electrode into two separate semi-cylindrical haif electrodes 7 8 and 89 as illustratively shown in FIGURE 5;
  • the D.-C. polarizing potential is applied between the half electrodes 73 and St), and a center tap from the polarizing potential is connected to the inner continuous cylinder electrode 82.
  • the two A.-C. connections will remain on the external surfaces 78 and 89 of the ceramic cylinder and thereby increase the convenience of the assembly.
  • a plurality of crystal plates 24, as shown in FIGURE 2 may be provided with all the positive polarities connected together as shown.
  • Suitable electrical conducting leads '70 and '72 conect the crystal plate electrodes 26 to the terminals 44 so that electrical operating power may be supplied to the transducer, through the cable 46.
  • the crystals of FIGURE 2 may be replaced by other materials, as for example, a stack of magnetostrictive elements or by a polarized polycrystaline ceramic such as barium titanate or lead zirconate as illustrated in FIGURE 3.
  • a polarized polycrystaline ceramic such as barium titanate or lead zirconate as illustrated in FIGURE 3.
  • the crystal plates 24 of FIGURE 2 have been replaced by the polarized ceramic cylinder 74.
  • the loaded ceramic cylinder '74 will operate at reduced resonant frequency for the same reason described above with the within their true spirit and scope.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate fiexlbly mounted to said housing structure and secured to said transducer means, a solid weight member attached to said electromechanical transducer means, flexible suspension means for supporting said solid weight member from said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said exteriorly sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within .5 I/ said exteriorly sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through sa1d passageway, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted to said housing structure and secured to said transducer means, said vibratile plate being formed with cellular inclusions of gas to reduce the density of said plate, a solid weight member attached to said electromechanical transducer means, flexible suspension means supporting said solid member from said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through said passageway, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means having first and second spaced apart plane surfaces capable of being set into vibration by the application of an alternating current, a fixed housing structure definingan enclosure for said transducer means, a vibratile plate flexibly mounted to said housing structure and attached to said first plane surface of said transducer means, a solid weight member having a plane surface attached to said second plane surface of said electromechanical transducer means, flexible suspension means for supporting said solid weight member in said housing structure, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means formed of a plurality of stacked piezoelectric plates capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted in said housing structure and attached to said transducer means, a weight member attached to said electromechanical transducer means, flexible suspension means for supporting said weight member from said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through the passageway and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means formed of polarized ceramic material capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted to said housing structure and attached to said transducer means, a weight member secured to said electromechanical transducer means, flexible suspension means for supporting said weight member from said housing structure, a flexible chamber member defining a sealed compartment, said sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through said passageway and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
  • said polarized ceramic material is in the form of a polarized ceramic cylinder having first and second plane surfaces respectively at opposite ends or" the cylinder, said first plane surface being attached to said vibratile plate and said second plane surface being attached to said solid weight member.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination or" electromechanical transducer means having a pair of parallel plane surfaces capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted in said housing structure and attached to one of said parallel plane surfaces of said transducer means, a weight member secured to the other parallel plane surface of said electromechanical transducer means, flexible suspension means for supporting said weight member from said housing means, a flexible chamber member defining a compartment, said compartment being in fluid communication with the enclosure of said housing structure, -a fluid disposed within the enclosure of said housing means and within said compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the compartment.
  • an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means having first and second, spaced-apart, parallel plane surfaces, electrical conductor means connected to said transducer means for applying an alternating current to set the transducer means into vibration, a housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted in said housing structure and attached to said first parallel plane surface of said electromechanical transducer means and a weight member secured to said second parallel plane surface of said electromechanical transducer means.

Description

Aug. 3, 1965 F. MASSA 3,199,071 ELECTROACOUSTIC TRANSDUCER CONSTRUCTION SUITABLE FOR OPERATION IN DEEP WATER Filed April 20. 1961 ATTORNEYS.
United States Patent F 3,199,071 ELECTRGACGUSTIQ TRANEDUCER CONSTRUG TKQN SUITABLE EUR fiPERATEON EN DEER? WATER Frank Massa, Cohasset, l lorfolh, Mass, assignor, by rncsne assignments, to Dynamics (lorporation of America, New York, N.Y., a corporation of New York Filed Apr. 20, 1961, Ser. No. 104,42ti 16 Claims. (Cl. 346-) This invention relates generally to underwater sound transducers and more particularly to new and improved electro-acoustic transducers adapted for the conversion of electrical energy to acoustic energy and also for the converison of acoustic energy to electrical energy;
It is well known in the art that an efficient electroacoustic transducer may be designed by employing piezoelectric materials for the conversion of electrical signals to mechanical vibrations. A conventional design of such a transducer makes use of an assembly of piezoelectric expander plates, cut from ammonium dihydrogen phosphate or some other suitable piezoelectric material, which are operated at their natural resonant frequency as illustrated, for example, in U.S. Patent 2,521,642 Such a design is limited to relatively high frequency efiicient operation because the natural frequency of typical prior art crystal plate assemblies usually falls in the frequency range above 15,000 cycles per second. For lower frequencies, the plates of these prior art arrangements become impractically long in their dimensions and are subject to easy fracture when their assembly is attempted.
Accordingly, it is a general object of this invention to improve the construction of underwater transducers, and especially transducers operating at frequencies generally in the region below approximately 15,000 cycles per second.
Another object of this invention is to provide a new and highly efiicient transducer construction which is pres sure equalized so that satisfactory operation can be achieved at great submerged depths under water.
It is still another object of this invention to provide a transducer of an etficient size wherein the radiating surface occupies a large portion of the housing dimensions.
It is another object of the invention to provide a transducer unit that may be conveniently assembled in multiple arrays whereby a very large radiating surface may be achieved with low manufacturing cost.
Other objects of the invention will become obvious to those skilled in the art from the following description in which the novel features which characterize the invention are set forth with particularity in the appended claims. The invention, itself, however, both as to its organization and method of operation, as well as advantages thereof, will best be understood from the following description of several embodiments thereof taken in conjunction with the accompanying drawings wherein:
FIGURE 1 is an end View showing the radiating surface of a new transducer embodying the invention;
FIGURE 2 is an elevational View, partially in cross section, of a new transducer taken along the line 22 of FIGURE 1;
FIGURE 3 is a partial sectional view, similar to FIG- URE 2, showing another illustrative embodiment of active transducer element adapted for use in the transducer assembly of the present invention;
FIGURE 4 is a perspective view of one of the crystal plates used in the embodiment of FIGURE 2 and arsaan Patented Aug. 3, 1965 FIGURE 5 is a perspective view of a split polarized ceramic cylinder which may be used as an alternative construction to the illustrative embodiment of FIGURE 3.
Referring now to the drawings, and more particularly to EGURE 1 thereof, the reference numeral 10 identifies the radiating plane surface of a transducer assembly 12. Although the radiating surface 10 is shown as a square, it will be appreciated that any other configuration, such as a circle or a polygon could be used.
Referring now to FIGURE 2, the transducer assembly 12 is shown as comprising a vibratile plate member 14 mounted within the frame-like portion 16 of the housing structure and flexibly attached to the housing structure by the molded rubber member 13. The rubber member 18 also is molded over the front radiating surface of the vibratile plate member 14 to provide a protective surface 2% for permitting improved long-life performance under water.
Advantageously, a cylindrical housing member 22 is secured as by brazing or any other suitable means, to the frame-like portion 16 to provide a completely sealed 7 housing to enclose the active transducer assembly. In accordance with a feature of this invention, the unique transducer structure comprises the vibratile plate member 14 and an assembly of piezoelectric crystal plates 24, such as 45 Z-cut ammonium dihydrogen phosphate, or 45 X-cut rochelle salt, or any other piezoelectric crystals which may be set into vibration by the application of an alternat ing voltage to a set of electrodes 26. The crytsal plate assembly is firmly bonded to a prepared flat face 84 of the Vibratile plate member 14, and to a similarly prepared flat surface 86 of a weight 28 as shown in FIGURE 2. A thin insulating Bakelite sheet (not shown) may be interposed and securely bonded between the ends of the crystal plates 24 and the surfaces of the adjoining plate 14 j and weight 28, if desired.
The purpose of providing the weight member 28 to load the crystal structure is to resonate the vibrating crystals at a lower frequency than would be possible were the loading weight omitted. In order that the crystal vibration amplitude may be held at a minimum with the corresponding advantageous reduction in stress, it is advantageous to make the vibratile plate 14 as light as possible, While making most of the load for frequency reduction reside in the non-radiating weight member 28. The vibratile plate 14 therefor, in one illustrative embodiment, is made of aluminum and, in cases where still further weight reduction is desired, the aluminum may be cast as a porous sponge-like mass which will preserve the rigidity of the plate, which is essential for satisfactory radiation of sound under water. The vibratile plate 14 illustratedin FIGURE 2 is shown as a porous spongelike aluminum mass having inclusions of gas pockets 88 dispersed through its volume whereby its density is reduced.
The magnitude of the weight 23 is adjusted to result in a combined resonant frequency of the crystal plates 24, and the masses of the plate 14 and Weight 28 as desired for the operating frequency of the transducer. Advan tageously a flexible spider member 343 is securely fastened to the center of the weight 28 as by the threaded fastener and spacer 34, and is also secured at its periphery to a ring member 36, which, in turn, is secured by any suitable means, such as brazing or welding, to the inner periphery of the housing structure 22. In accordance with the invention, the spider member 3% has transverse rigidity and keeps the weight 23 from being sheared off as at the bonded crystal surface during shock and vibration ml? "the transducer.
An end cap 38 is fastened to the housing 22, as by means of the radially dispose-d screws 4%. Advantageously an O-ring 42 provides a seal between end cap 38 and housing 22, as shown. Insulated terminals 44 are provided to permit transfer of the electrical connections from the electrodes 26 of the crystal plates 24 to the external cable 46'. A cable gland housing 43 is fastened .to the end cap 38 as by means of the screws 50 and and O-ring 52 provides the necesary underwater seal. The cable 46 is sealed by the assembly of the compression rubber gland 54, the washer 56 and the nut 58. Those .skilled in the art will appreciate that nut 58 is tightened sufliciently to provide compression of the gland 54 to the surface of the cable In order to pressure equalize the assembly so that the structure will not be damaged due to the higher static pressure developed in deep water, it is a feature of this invention to provide a flexible rubber sleeve 6t? which is :sealed to opposite ends of the cylindrical housing 22, as
by means of the metallic bands 62. or other suitable means. An orifice 64 is formed through the wall of the housing 22, as shown, to provide communication between the inner enclosure of the housing 22 and the reservoir enclosure 66 defined by the sealed rubber sleeve so and the outer surface of housing 22. A suitable fluid, such as castor oil, fills the inner enclosure of the trans :ducer assembly and the reservoir enclosure 66 of the as- :sembly. The oil may be poured into the transducer before the attachment of the end cap 38, and the rubber sleeve tit) may be pulled out from the housing as by means of a vacuum, to allow the oil to run into the formed reservoir enclosure 66.
In accordance with a further feature of this invention, :a low acoustic impedance member 68, such as cork, is placed inside the transducer structure. The members 68 serve as a pressure release during the vibration of the plate 14 during operation of the transducer and prevents other words, the compression of the air cells prevents the pressure from being built up in the fluid, and there- "fore, serves as a pressure release.
The above description of the new low frequency transducer contemplates the use of piezoelectric crystals forming the vibrating transducer material. An illustrative detailed showing of a 45 Z-cut ammonium di-hydrogen' phosphate crystal which is suitable for use in the inven- '-tion is shown in FIGURE 4 of the drawing. A pair of metaltic electrode surfaces 26 are cemented to the opposite faces of the crystal plate 24 as shown. When potential surface.
crystal structure. The electrical conducting leads 70' and 72' connect the polarized ceramic cylinder 74 to the terminals of a suitable power cable so that electrical operating power may be supplied to the transducer.
In accordance with another feature of this invention, it has been found advantageous to split the outer cylindrical electrode into two separate semi-cylindrical haif electrodes 7 8 and 89 as illustratively shown in FIGURE 5; In polarizing the ceramic cylinder, the D.-C. polarizing potential is applied between the half electrodes 73 and St), and a center tap from the polarizing potential is connected to the inner continuous cylinder electrode 82. By this polarizing arrangement, the two A.-C. connections will remain on the external surfaces 78 and 89 of the ceramic cylinder and thereby increase the convenience of the assembly. It will be appreciated by those skilled in the art that it is, of course, equally possible to polarize the'cer'amic cylinder in a conventional manner usmg a continuous outer cylindrical electrode for one potential surface and the inner cylindrical electrode for the second The inner electrode connecting wire would then be passed through a hole that would be provided through the loading weight 28 in order to permit electrical connection to be established between the inner surface of the cylinder andthe terminals 44.
While there has been shown and described several specific embodiments of the present invention, it will of course, be understood that various modifications and alternative constructions may be made without departing from the true spirit and scope of the invention. Therefore, it is intended by the appended claims to cover all such modifications and alternative constructions as fall alternating potentials are applied to the electrodes 26, i
the crystal plate will vibrate correspondingly in a manner well known in the art. Advantageously, a plurality of crystal plates 24, as shown in FIGURE 2, may be provided with all the positive polarities connected together as shown. Suitable electrical conducting leads '70 and '72 conect the crystal plate electrodes 26 to the terminals 44 so that electrical operating power may be supplied to the transducer, through the cable 46.
As an alternate transducer material which may be utilized in the invention, the crystals of FIGURE 2 may be replaced by other materials, as for example, a stack of magnetostrictive elements or by a polarized polycrystaline ceramic such as barium titanate or lead zirconate as illustrated in FIGURE 3. As shown in FIG URE 3, the crystal plates 24 of FIGURE 2 have been replaced by the polarized ceramic cylinder 74. The loaded ceramic cylinder '74 will operate at reduced resonant frequency for the same reason described above with the within their true spirit and scope.
What is claimed as the invention is: w l. The improvement of an electroacoustic transducer assemblyfo'r generatin underwater sound comprising the combination of electromechanical transducer means hav* ing first and second plane surfaces spaced from each other and capable of being set into vibration by the appli= cation of an alternating current to sai-d transducer means a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted t6 said housing structure, and secured to said first plane surface of said transducer means, a solid weight member having a plane surface secured to said second plane surface of said transducer means, flexible suspension means for supporting said solid Weight member in said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said exteriorly sealed compartment being in internal fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said exteriorly sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the exteriorly sealed compartment, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
2. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate fiexlbly mounted to said housing structure and secured to said transducer means, a solid weight member attached to said electromechanical transducer means, flexible suspension means for supporting said solid weight member from said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said exteriorly sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within .5 I/ said exteriorly sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through sa1d passageway, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
3. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted to said housing structure and secured to said transducer means, said vibratile plate being formed with cellular inclusions of gas to reduce the density of said plate, a solid weight member attached to said electromechanical transducer means, flexible suspension means supporting said solid member from said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through said passageway, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
4-. The improvement of an electroacoustic transducer assembly in accordance with claim 3 wherein said housing structure and sealed enclosure are filled with a liquid.
5. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means having first and second spaced apart plane surfaces capable of being set into vibration by the application of an alternating current, a fixed housing structure definingan enclosure for said transducer means, a vibratile plate flexibly mounted to said housing structure and attached to said first plane surface of said transducer means, a solid weight member having a plane surface attached to said second plane surface of said electromechanical transducer means, flexible suspension means for supporting said solid weight member in said housing structure, and electrical terminal means on said housing structure for connecting external electrical power to said transducer means. 7
6. The improvement of an electroacoustic transducer assembly in accordance with claim wherein said vibratile plate is formed with cellular inclusions of gas to reduce the density of said plate.
7. The improvement of an electroacoustic transducer assembly in accordance with claim 5 wherein one face of said vibratile plate is exposed to the exterior of said housing structure and further comprising a flexible water impervious material covering the exposed face of said vibratile plate.
8. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means formed of a plurality of stacked piezoelectric plates capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted in said housing structure and attached to said transducer means, a weight member attached to said electromechanical transducer means, flexible suspension means for supporting said weight member from said housing structure, a flexible chamber member defining an exteriorly sealed compartment, said sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through the passageway and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
9. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means formed of polarized ceramic material capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted to said housing structure and attached to said transducer means, a weight member secured to said electromechanical transducer means, flexible suspension means for supporting said weight member from said housing structure, a flexible chamber member defining a sealed compartment, said sealed compartment being in fluid communication with the enclosure of said housing structure through a passageway formed in said housing structure, a fluid disposed within the enclosure of said housing structure and within said sealed compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the sealed compartment through said passageway and electrical terminal means on said housing structure for connecting external electrical power to said transducer means.
it). The improvement of an electroacoustic transducer assembly in accordance with claim 9 wherein said polarized ceramic material is in the form of a polarized ceramic cylinder having first and second plane surfaces respectively at opposite ends or" the cylinder, said first plane surface being attached to said vibratile plate and said second plane surface being attached to said solid weight member.
11. The improvement of an electroacoustic transducer assembly in accordance with ciaim 10 wherein said polarized ceramic cylinder is provided with at least two electrically separated metallic electrodes.
12. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination or" electromechanical transducer means having a pair of parallel plane surfaces capable of being set into vibration by the application of an alternating current, a fixed housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted in said housing structure and attached to one of said parallel plane surfaces of said transducer means, a weight member secured to the other parallel plane surface of said electromechanical transducer means, flexible suspension means for supporting said weight member from said housing means, a flexible chamber member defining a compartment, said compartment being in fluid communication with the enclosure of said housing structure, -a fluid disposed within the enclosure of said housing means and within said compartment, said fluid being capable of easily flowing between the enclosure of said housing structure and the compartment.
13. The improvement of an electroacoustic transducer assembly in accordance with claim 12 characterized in that said weight member is of greater mass than said vibratile plate.
14. The improvement of an electroacoustic transducer assembly for generating underwater sound comprising the combination of electromechanical transducer means having first and second, spaced-apart, parallel plane surfaces, electrical conductor means connected to said transducer means for applying an alternating current to set the transducer means into vibration, a housing structure defining an enclosure for said transducer means, a vibratile plate flexibly mounted in said housing structure and attached to said first parallel plane surface of said electromechanical transducer means and a weight member secured to said second parallel plane surface of said electromechanical transducer means.
7 8' 15. The improvement of an electroacoustic transducer tromechanical transducer means is maintained under a assemblyin accordance with claim 14 wherein the mass static pressure bias between said vibratile plate and said of said weight member is greater than the mass of said weight member.
vibratile plate. No references cited.
16. The improvement of an electroacoustic transducer 5 assembly in accordance with claim 14 wherein said elec- CHESTER L- JUSTUS, Primary Examiner.

Claims (1)

1. THE IMPROVEMENT OF AN ELECTROACOUSTIC TRANSDUCER ASSEMBLY FOR GENERATING UNDERWATER SOUND COMPRISING THE COMBINATION OF ELECTROMECHANICAL TRANSDUCER MEANS HAVING FIRST AND SECOND PLANE SURFACES SPACED FROM EACH OTHER AND CAPABLE OF BEING SET INTO VIBRATION BY THE APPLICATION OF AN ALTERNATING CURRENT TO SAID TRANSDUCER MEANS, A FIXED HOUSING STRUCTURE DEFINING AN ENCLOSURE FOR SAID TRANSDUCER MEANS, A VIBRATILE PLATE FLEXIBLY MOUNTED TO SAID HOUSING STRUCTURE, AND SECURED TO SAID FIRST PLANE SURFACE OF SAID TRANSDUCER MEANS, A SOLID WEIGHT MEMBER HAVING A PLANE SURFACE SECURED TO SAID SECOND PLANE SURFACE OF SAID TRANSDUCER MEANS, FLEXIBLE SUSPENSION MEANS FOR SUPPORTING SAID SOLID WEIGHT MEMBER IN SAID HOUSING STRUCTURE, A FLEXIBLE CHAMBER MEMBER DEFINING AN EXTERIORLY SEALED COMPARTMENT, SAID EXTERIORLY SEALED COMPARTMENT BEING IN INTERNAL FLUID COMMUNICATION WITH THE ENCLOSURE OF SAID HOUSING STRUCTURE THROUGH A PASSAGEWAY FORMED IN SAID HOUSING STRUCTURE, A FLUID DISPOSED WITHIN THE ENCLOSURE OF SAID HOUSING STRUCTURE AND WITHIN SAID EXTERIORLY SEALED COMPARTMENT, SAID FLUID BEING CAPABLE OF EASILY FLOWING BETWEEN THE ENCLOSURE OF SAID HOUSING STRUCTURE AND THE EXTERIOLY SEALED COMPARTMENT, AND ELECTRICAL TERMINAL MEANS ON SAID HOUSING STRUCTURE FOR CONNECTING EXTERNAL ELECTRICAL POWER TO SAID TRANSDUCER MEANS.
US104420A 1961-04-20 1961-04-20 Electroacoustic transducer construction suitable for operation in deep water Expired - Lifetime US3199071A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US104420A US3199071A (en) 1961-04-20 1961-04-20 Electroacoustic transducer construction suitable for operation in deep water

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US104420A US3199071A (en) 1961-04-20 1961-04-20 Electroacoustic transducer construction suitable for operation in deep water

Publications (1)

Publication Number Publication Date
US3199071A true US3199071A (en) 1965-08-03

Family

ID=22300390

Family Applications (1)

Application Number Title Priority Date Filing Date
US104420A Expired - Lifetime US3199071A (en) 1961-04-20 1961-04-20 Electroacoustic transducer construction suitable for operation in deep water

Country Status (1)

Country Link
US (1) US3199071A (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3263210A (en) * 1964-06-24 1966-07-26 Schloss Fred Wide band hydrophone
US3263208A (en) * 1963-09-12 1966-07-26 George R Douglas Pressure compensated transducer
US3284762A (en) * 1965-03-26 1966-11-08 Harry W Kompanek Mechanical-to-electrical transducer
US3337843A (en) * 1965-12-20 1967-08-22 Paul M Kendig Underwater transducer array for deep submergence
US3341721A (en) * 1964-12-16 1967-09-12 Honeywell Inc Transducer housing with flexible supports
US3474403A (en) * 1966-06-08 1969-10-21 Dynamics Corp Massa Div Electroacoustic transducer with improved shock resistance
US3539980A (en) * 1968-11-29 1970-11-10 Dynamics Corp America Underwater electroacoustic transducer which resists intense pressure
US3550071A (en) * 1968-05-10 1970-12-22 Krupp Gmbh Transducer system
US4704709A (en) * 1985-07-12 1987-11-03 Westinghouse Electric Corp. Transducer assembly with explosive shock protection
US4941202A (en) * 1982-09-13 1990-07-10 Sanders Associates, Inc. Multiple segment flextensional transducer shell
US5321333A (en) * 1993-04-06 1994-06-14 The United States Of America As Represented By The Secretary Of The Navy Torsional shear wave transducer

Non-Patent Citations (1)

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

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3263208A (en) * 1963-09-12 1966-07-26 George R Douglas Pressure compensated transducer
US3263210A (en) * 1964-06-24 1966-07-26 Schloss Fred Wide band hydrophone
US3341721A (en) * 1964-12-16 1967-09-12 Honeywell Inc Transducer housing with flexible supports
US3284762A (en) * 1965-03-26 1966-11-08 Harry W Kompanek Mechanical-to-electrical transducer
US3337843A (en) * 1965-12-20 1967-08-22 Paul M Kendig Underwater transducer array for deep submergence
US3474403A (en) * 1966-06-08 1969-10-21 Dynamics Corp Massa Div Electroacoustic transducer with improved shock resistance
US3550071A (en) * 1968-05-10 1970-12-22 Krupp Gmbh Transducer system
US3539980A (en) * 1968-11-29 1970-11-10 Dynamics Corp America Underwater electroacoustic transducer which resists intense pressure
US4941202A (en) * 1982-09-13 1990-07-10 Sanders Associates, Inc. Multiple segment flextensional transducer shell
US4704709A (en) * 1985-07-12 1987-11-03 Westinghouse Electric Corp. Transducer assembly with explosive shock protection
US5321333A (en) * 1993-04-06 1994-06-14 The United States Of America As Represented By The Secretary Of The Navy Torsional shear wave transducer

Similar Documents

Publication Publication Date Title
US2384465A (en) Submarine signaling appabatus
US3142035A (en) Ring-shaped transducer
US2565158A (en) Hydraulic electromechanical transducer
US2962695A (en) Resonant low-frequency transducer
US3199071A (en) Electroacoustic transducer construction suitable for operation in deep water
US3274537A (en) Flexural-extensional electro-mechanical transducer
US2787777A (en) Ceramic transducer having stacked elements
US3328751A (en) Electroacoustic transducer
US3922572A (en) Electroacoustical transducer
US3025359A (en) Vibration-compensated pressure sensitive microphone
US3735159A (en) Method and apparatus for translating ultrasonic energy
US3094636A (en) Underwater transducer
US2768364A (en) Underwater transducer having annular elements
US2895061A (en) Piezoelectric sandwich transducer
US3474403A (en) Electroacoustic transducer with improved shock resistance
US4219889A (en) Double mass-loaded high power piezo-electric underwater transducer
US2413462A (en) Transducer
US3460061A (en) Electroacoustic transducer with improved shock resistance
US3525071A (en) Electroacoustic transducer
US2490236A (en) Piezoelectric transducer
US2746026A (en) Half wave annular transducer
US3739327A (en) Electroacoustic transducers of the mass loaded vibratile piston type
US3546497A (en) Piezoelectric transducer element
US3497731A (en) Bender type transducers
US3150347A (en) Underwater transducer element