US3094636A - Underwater transducer - Google Patents
Underwater transducer Download PDFInfo
- Publication number
- US3094636A US3094636A US591602A US59160256A US3094636A US 3094636 A US3094636 A US 3094636A US 591602 A US591602 A US 591602A US 59160256 A US59160256 A US 59160256A US 3094636 A US3094636 A US 3094636A
- Authority
- US
- United States
- Prior art keywords
- disk
- ceramic
- transducer
- vibrator
- ring
- 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
Links
- 239000011343 solid material Substances 0.000 claims description 2
- 239000000919 ceramic Substances 0.000 description 23
- 239000004020 conductor Substances 0.000 description 9
- 239000000463 material Substances 0.000 description 6
- 238000005452 bending Methods 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 239000011810 insulating material Substances 0.000 description 3
- 229910052709 silver Inorganic materials 0.000 description 3
- 239000004332 silver Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 230000003467 diminishing effect Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 229920001084 poly(chloroprene) Polymers 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
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
- B06B1/0644—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 a single piezoelectric element
- B06B1/0655—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 a single piezoelectric element of cylindrical shape
Definitions
- An object of the invention is to provide a simple, eifieient, reliable and inexpensive transducer of this type.
- a more specific object is to provide an effective transducer having a single electromechanically-sensitive vibratile element of relatively small cross-sectional area and a sound-radiating and absorbing face of substantially larger area.
- transducers having a single longitudinal-vibratile ceramic element, one end of which constitutes the working face in acoustic coupling relation with the water.
- the coupling efficiency and directional characteristics of a transducer vary with the area of the working face, and it is often impractical to employ ceramic elements of large enough end area to provide the desired directional characteristics.
- the usual solution has been to use an array of small elements.
- One such transducer is disclosed and claimed in Camp et a1.
- Such an array has the advantages over a single large solid ceramic cylinder of being much cheaper, because of difficulties in manufacturing large ceramic elements.
- the transducer of the present invention utilizes a single ceramic element and has substantially the same electrical and acoustical characteristics as the seven-element transducer of the prior application. This is accomplished by employing a composite integral vibrator element consisting of a longitudinally vibratile ceramic ring having a rigid disk bonded to its front end and a heavy ring bonded to its rear end.
- the disk constitutes the working face and is made as rigid as possible to vibrate as a piston; to this end, it is preferably relatively thick and of some relatively light, strong material, such as aluminum.
- the rear ring is to provide mass at the rear end of the vibrator element and is preferably made of lead or other dense material. It is substanatially coextensive laterally with the ceramic ring, so that it is not subject to bending stresses, and its thickness is determined by the mass required and not by stiffness requirements.
- FIG. 2 is a sectional view taken along the line II-II of FIG. 1.
- the recess 11a is located adjacent one end of the body, and the latter 3,094,635 Patented June 18, 1963 is extended therefrom in wedge form to a leading edge 112 which is pointed toward the forward end of the boat so that it divides the water and reduces turbulence at the active face 11d.
- a cable 12 containing the electrical conductors is preferably extended from the rear end of the body (the end opposite the leading edge 112). The cable extends through an aperture in a neck portion 11 of the body which is compressed tightly about the cable by a clamp 13.
- the front end of the recess 11a is closed by a rubber sound window 14, the outer surface of which is flush with the front surface 11d of the remainder of the body.
- the vibrator 10 is a composite element comprising an electromechanicallyresponsive ring 10a, a front aluminum disk 10b, and a rear lead ring 100, all firmly bonded together at their contact faces.
- the ceramic and lead rings 10a and 10c have cylindrical inner and outer faces, and flat end faces.
- the outside diameter disk 10b is at least as great as that of the ceramic ring 10a, and is preferably slightly larger, as shown in the drawing. To facilitate axial alignment of the ceramic and lead rings in assembly (as by use of a mandril), their inside diameters may be exactly the same. Likewise, to facilitate axial alignment of the disk 10b with the rings, the outside diameter of the disk and lead ring may be the same.
- the hollow rear mass in the form of the lead ring 100, has the advantage of providing a desirable mass at the rear end of the vibrator that may be constructed of relatively weak material (with respect to bending).
- a watertight casing defining a cavity and having juxtaposed flat front and rear walls, said front wall constituting a sound window; a layer of acoustic insulating material positioned against said rear wall; a unitary longitudinally-vibratile vibrator positioned in said cavity and extending between and supported by said layer of insulating material and said front wall, respectively, the front end of the vibrator being bonded to said front wall for acoustic connection therewith and present construction lateral support thereby; said vibrator comprising a longitudinally vibratile, electromechanically-responsive element and front and rear mass element-s bonded thereto,
- An electromechanical transducer system comprising electromechanical transducer means sandwiched between two pieces of solid materials which have relatively dissimilar densities and constituting with said pieces a mechanical vibrator, said system being dimensioned to vibrate as a half-wave vibrator in the direction of a line through said pieces and said transducer means.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Transducers For Ultrasonic Waves (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Description
June 18, 1963 B. B. GAULD 3,094,536
UNDERWATER TRANSDUCER Filed June 15, 1956 I2 I //f I3 INVENTOR.
B. B. GA ULD ATTORNEY United States Patent "ice This invention relates to underwater transducers utilizing electromechanically-responsive ceramic elements for converting electric oscillations into sound waves, and vice versa.
An object of the invention is to provide a simple, eifieient, reliable and inexpensive transducer of this type.
A more specific object is to provide an effective transducer having a single electromechanically-sensitive vibratile element of relatively small cross-sectional area and a sound-radiating and absorbing face of substantially larger area.
Other more specific objects and features of the invention will appear from the description to follow.
It is old to use transducers having a single longitudinal-vibratile ceramic element, one end of which constitutes the working face in acoustic coupling relation with the water. However, the coupling efficiency and directional characteristics of a transducer vary with the area of the working face, and it is often impractical to employ ceramic elements of large enough end area to provide the desired directional characteristics. The usual solution has been to use an array of small elements. One such transducer is disclosed and claimed in Camp et a1. Patent No. 2,797,399, issued June 25, 1957, assigned to The Bendix Corporation, which transducer contains an array of seven small solid cylindrical ceramic elements. Such an array has the advantages over a single large solid ceramic cylinder of being much cheaper, because of difficulties in manufacturing large ceramic elements.
The transducer of the present invention utilizes a single ceramic element and has substantially the same electrical and acoustical characteristics as the seven-element transducer of the prior application. This is accomplished by employing a composite integral vibrator element consisting of a longitudinally vibratile ceramic ring having a rigid disk bonded to its front end and a heavy ring bonded to its rear end. The disk constitutes the working face and is made as rigid as possible to vibrate as a piston; to this end, it is preferably relatively thick and of some relatively light, strong material, such as aluminum. The rear ring is to provide mass at the rear end of the vibrator element and is preferably made of lead or other dense material. It is substanatially coextensive laterally with the ceramic ring, so that it is not subject to bending stresses, and its thickness is determined by the mass required and not by stiffness requirements.
A full understanding of the invention may be had from the following detailed description, with reference to the drawing, in which:
FIG. 1 is a front view of a transducer in accordance with the invention.
FIG. 2 is a sectional view taken along the line II-II of FIG. 1.
Referring to the drawing, the transducer therein disclosed comprises a body 11 molded or otherwise formed from rubber or similar material defining a closed recess 11a in which a vibrator 10 is positioned. Two mounting holes 1112 are provided near the middle of the body for screwing or bolting it against the under surface of a boat with the rear surface 110 lying against the boat and the front surface 11d facing downwardly.
It will be observed from FIG. 1 that the recess 11a is located adjacent one end of the body, and the latter 3,094,635 Patented June 18, 1963 is extended therefrom in wedge form to a leading edge 112 which is pointed toward the forward end of the boat so that it divides the water and reduces turbulence at the active face 11d. A cable 12 containing the electrical conductors is preferably extended from the rear end of the body (the end opposite the leading edge 112). The cable extends through an aperture in a neck portion 11 of the body which is compressed tightly about the cable by a clamp 13.
The front end of the recess 11a is closed by a rubber sound window 14, the outer surface of which is flush with the front surface 11d of the remainder of the body.
The vibrator 10 is a composite element comprising an electromechanicallyresponsive ring 10a, a front aluminum disk 10b, and a rear lead ring 100, all firmly bonded together at their contact faces. The ceramic and lead rings 10a and 10c have cylindrical inner and outer faces, and flat end faces. The outside diameter disk 10b is at least as great as that of the ceramic ring 10a, and is preferably slightly larger, as shown in the drawing. To facilitate axial alignment of the ceramic and lead rings in assembly (as by use of a mandril), their inside diameters may be exactly the same. Likewise, to facilitate axial alignment of the disk 10b with the rings, the outside diameter of the disk and lead ring may be the same.
The vibratory force of the ceramic ring is preferably applied to the disk 1012 at an annular zone of the latter spaced radially inwardly from the outer cylindrical face thereof, to increase the area of the disk that can be used with a given size of ceramic ring without increasing the bending stresses in the disk. In this connection, it will be understood that a large disk diameter is desirable to improve the efficiency of transfer of acoustic energy between it and the water, and to improve the directional characteristics. The use of a disk of larger diameter than the outside diameter of the ceramic ring has the further advantage that it permits a smaller and cheaper ceramic ring to be used, and also reduces the bending stresses in the disk and its tendency to vibrate in secondary modes.
The ceramic ring has the usual silver electrodes 10d and 10e on its front and rear annular faces, respectively, to which are connected the conductors in the cable 12. The electrodes may be formed by painting the front and rear surfaces of the ceramic element with silver paint and baking them to leave a thin film of metallic silver.
The longitudinal or axial dimension of the vibrator assembly is less than the depth of the recess 11a, and the vibrator is supported with the front face of the disk 1% in contact with the sound window 14 by a disk 15 of acoustic insulating material such as cellular neoprene. This disk 15 fills the space between the rear wall of the recess 11a and the lead ring so that the vibrator 10 is supported within the body by the disk 15 and the diaphragm 14. The front face of the disk 10b is firmly bonded to the sound window 14, so that the latter prevents any lateral shifting of the vibrator within the recess 11a.
It is usually desirable to provide in the cable 12 a central conductor 12a and a concentric conductor 12b surrounding the conductor 12a. The conductor 12a is connected to the rear electrode 102 of the ceramic element 10a, and the outer conductor 12b is connected to the front electrode 10d. The concentric conductor 12b is preferably at ground potential, and to shield the electrode 10c from extraneous electric fields a metallic shield disk 16 is provided between the disk 15 and the rear wall of the recess 11a and is connected to the conductor 12b of the cable.
The ceramic element 10a may be of any well known material, such as barium titanate, and is prepolarized in accordance with well-known practice so that it responds to mechanical vibrations applied thereto through the sound window 14 to generate potential between its electrodes d and 102, and responds to alternating electrical potentials applied to said electrodes to expand and contract longitudinally and thereby cause the entire element 10 to vibrate longitudinally by contraction and expansion, with resultant vibratory movement of the front face of the disk 10b. The entire vibrating device is preferably of length equal to one-half the wave length of sound therein at the operating frequency. At a frequency in the neighborhood of 100,000 cycles per second, the ceramic element 10a may be .245 inch thick; the aluminum disk 1 10b may be .301 inch thick; and the lead ring 100 may be .125 inch thick.
The particular advantages of the may be summarized as follows:
(a) The use of the hollow ceramic cylinder enables a reduction of the capacity without diminishing the effective area of the vibrating face in acoustic coupling relation with the water.
(b) The hollow rear mass, in the form of the lead ring 100, has the advantage of providing a desirable mass at the rear end of the vibrator that may be constructed of relatively weak material (with respect to bending).
(c) The combination of the ceramic ring with the front disk of larger diameter provides an active element employing a relatively small amount of material with a working face of relatively large area.
Although for the purpose of explaining the invention a particular embodiment thereof has been shown and described, obvious modifications will occur to a person skilled in the art, and I do not desire to be limited to the exact detail-s shown and described.
"I claim:
1. In an underwater transducer: a watertight casing defining a cavity and having juxtaposed flat front and rear walls, said front wall constituting a sound window; a layer of acoustic insulating material positioned against said rear wall; a unitary longitudinally-vibratile vibrator positioned in said cavity and extending between and supported by said layer of insulating material and said front wall, respectively, the front end of the vibrator being bonded to said front wall for acoustic connection therewith and present construction lateral support thereby; said vibrator comprising a longitudinally vibratile, electromechanically-responsive element and front and rear mass element-s bonded thereto,
. said front element being of lesser density and larger di- 6. "A transducer according to claim 5 in which said mass elements have the same external diameter and the electromechanically-responsive element has a lesser external diameter.
7. An electromechanical transducer system comprising electromechanical transducer means sandwiched between two pieces of solid materials which have relatively dissimilar densities and constituting with said pieces a mechanical vibrator, said system being dimensioned to vibrate as a half-wave vibrator in the direction of a line through said pieces and said transducer means.
References Cited in the file of this patent UNITED STATES PATENTS 2,508,544 Shaper May 23, 1950 2,520,938 Klein Sept. 5, 1950 2,638,577 Harris May 12, 1953 2,753,543 Rymes July 3, 1956 2,797,399 Camp June 25, 1957 FOREIGN PATENTS 527,250 Belgium Mar. 31, 1954 OTHER REFERENCES Sonics, Hueter-Bolt, pub. by John Wiley and Sons, Inc., New York, copyright 1955, pages 97-99.
Mil-C-17831A (Ships), February 16, 1956, Military Specification Communication Set, Sonar, Swimmers Underwater Telephone, 21 pp., Fig. 3 relied on (page 21).
Claims (1)
- 7. AN ELECTROMECHANICAL TRANSDUCER SYSTEM COMPRISING ELECTROMECHANICAL TRANSDUCER MEANS SANDWICHED BETWEEN TWO PIECES OF SOLID MATERIALS WHICH HAVE RELATIVELY DISSIMILAR DENSITIES AND CONSTITUTING WITH SAID PIECES A MECHANICAL VIBRATOR, SAID SYSTEM BEING DIMENSIONED TO VIBRATE AS A HALF-WAVE VIBRATOR IN THE DIRECTION OF A LINE THROUGH SAID PIECES AND SAID TRANSDUCER MEANS.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US591602A US3094636A (en) | 1956-06-15 | 1956-06-15 | Underwater transducer |
GB15626/57A GB815873A (en) | 1956-06-15 | 1957-05-16 | Underwater transducer |
DEB44826A DE1105211B (en) | 1956-06-15 | 1957-06-01 | Underwater transmitter for sound and ultrasonic vibrations |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US591602A US3094636A (en) | 1956-06-15 | 1956-06-15 | Underwater transducer |
Publications (1)
Publication Number | Publication Date |
---|---|
US3094636A true US3094636A (en) | 1963-06-18 |
Family
ID=24367117
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US591602A Expired - Lifetime US3094636A (en) | 1956-06-15 | 1956-06-15 | Underwater transducer |
Country Status (3)
Country | Link |
---|---|
US (1) | US3094636A (en) |
DE (1) | DE1105211B (en) |
GB (1) | GB815873A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3460061A (en) * | 1965-10-07 | 1969-08-05 | Dynamics Corp America | Electroacoustic transducer with improved shock resistance |
US3553393A (en) * | 1966-06-10 | 1971-01-05 | Akg Akustische Kino Geraete | Electro-acoustic transducer housing for dampening vibrations |
US3573515A (en) * | 1969-02-28 | 1971-04-06 | United States Steel Corp | Transducer-holding block adapted to be mounted within a liquid-filled work-engaging roller |
US3631383A (en) * | 1969-07-25 | 1971-12-28 | Bendix Corp | Piezoelectric transducer configuration |
US3806909A (en) * | 1972-03-23 | 1974-04-23 | Texas Instruments Inc | Stress sensor for a perimeter intrusion detector system |
US4012649A (en) * | 1975-10-09 | 1977-03-15 | Teledyne Industries, Inc. | Piezoelectric stress/strain intrusion detectors |
US4972390A (en) * | 1989-04-03 | 1990-11-20 | General Instrument Corp. | Stack driven flexural disc transducer |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3068446A (en) * | 1958-08-21 | 1962-12-11 | Stanley L Ehrlich | Tubular electrostrictive transducer with spaced electrodes and loading masses |
US3217288A (en) * | 1961-07-26 | 1965-11-09 | Claude C Sims | Noise measurement hydrophone |
US3336573A (en) * | 1966-09-14 | 1967-08-15 | Texaco Inc | Crystal pressure sensitive geophones for use in soft earth |
US4059098A (en) * | 1975-07-21 | 1977-11-22 | Stanford Research Institute | Flexible ultrasound coupling system |
DE3146949A1 (en) * | 1981-11-26 | 1983-06-01 | Siemens AG, 1000 Berlin und 8000 München | Ultrasonic transducer |
DE19742294A1 (en) * | 1997-09-25 | 1999-04-01 | Elster Produktion Gmbh | Sound receiver or producer |
DE10000924B4 (en) * | 2000-01-12 | 2011-11-24 | Volkswagen Ag | ultrasonic sensor |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE527250A (en) * | ||||
US2508544A (en) * | 1947-03-01 | 1950-05-23 | Brush Dev Co | Electroacoustic transducer device |
US2520938A (en) * | 1944-10-07 | 1950-09-05 | Klein Elias | Tourmaline crystal transducer |
US2638577A (en) * | 1949-11-15 | 1953-05-12 | Harris Transducer Corp | Transducer |
US2753543A (en) * | 1952-08-28 | 1956-07-03 | Raytheon Mfg Co | Transducers |
US2797399A (en) * | 1955-03-08 | 1957-06-25 | Bendix Aviat Corp | Underwater transducer |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR597706A (en) * | 1925-05-06 | 1925-11-27 | Indirect vibratory massage method and device for performing this method | |
FR896806A (en) * | 1940-02-22 | 1945-03-05 | Atlas Werke Ag | Piezoelectric oscillator device |
BE509494A (en) * | 1951-03-06 |
-
1956
- 1956-06-15 US US591602A patent/US3094636A/en not_active Expired - Lifetime
-
1957
- 1957-05-16 GB GB15626/57A patent/GB815873A/en not_active Expired
- 1957-06-01 DE DEB44826A patent/DE1105211B/en active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE527250A (en) * | ||||
US2520938A (en) * | 1944-10-07 | 1950-09-05 | Klein Elias | Tourmaline crystal transducer |
US2508544A (en) * | 1947-03-01 | 1950-05-23 | Brush Dev Co | Electroacoustic transducer device |
US2638577A (en) * | 1949-11-15 | 1953-05-12 | Harris Transducer Corp | Transducer |
US2753543A (en) * | 1952-08-28 | 1956-07-03 | Raytheon Mfg Co | Transducers |
US2797399A (en) * | 1955-03-08 | 1957-06-25 | Bendix Aviat Corp | Underwater transducer |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3460061A (en) * | 1965-10-07 | 1969-08-05 | Dynamics Corp America | Electroacoustic transducer with improved shock resistance |
US3553393A (en) * | 1966-06-10 | 1971-01-05 | Akg Akustische Kino Geraete | Electro-acoustic transducer housing for dampening vibrations |
US3573515A (en) * | 1969-02-28 | 1971-04-06 | United States Steel Corp | Transducer-holding block adapted to be mounted within a liquid-filled work-engaging roller |
US3631383A (en) * | 1969-07-25 | 1971-12-28 | Bendix Corp | Piezoelectric transducer configuration |
US3806909A (en) * | 1972-03-23 | 1974-04-23 | Texas Instruments Inc | Stress sensor for a perimeter intrusion detector system |
US4012649A (en) * | 1975-10-09 | 1977-03-15 | Teledyne Industries, Inc. | Piezoelectric stress/strain intrusion detectors |
US4972390A (en) * | 1989-04-03 | 1990-11-20 | General Instrument Corp. | Stack driven flexural disc transducer |
Also Published As
Publication number | Publication date |
---|---|
DE1105211B (en) | 1961-04-20 |
GB815873A (en) | 1959-07-01 |
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