Patent GB2120902A successfully refreshed from Google Patents.
GB2120902A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
Underwater acoustic devices
Assignee: SECR DEFENCE
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Filing: 1983-05-24
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Granted: —
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Expires: 2003-05-24
Abstract
Abstract An underwater acoustic transducer which, for example, is suspended in water from a buoy, comprises a thin gas-pressurised spherical structure (1) composed of polymeric piezoelectric material, preferably polyvinylidene difluoride (PVDF), which has a high piezoelectric stress constant and a low Young's modulus, films of layers (10, 11) of electrically conductive material on the inner and outer surfaces of the structure, and electrical terminal means (12,13) for connecting the films or layers with cables (6,7). The transducer is preferably inflatable with nitrogen through above (9). <IMAGE>
Inventors
- 👤 Dennis Stansfield
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-10-23 13:37
CPC Classifications
H; H04; H04R; H04R17/00; H04R17/005; B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0688
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
64 words
An underwater acoustic device comprising a thin spherical structure composed of polymeric piezoelectric material having a high piezoelectric stress constant and a low Young's modulus, wherein the spherical structure is gas pressurised, a film or layer of electrically conductive material on the inner end outer surfaces of the structure, and electrical terminal means contacting the film or layer on said inner and outer surfaces.
Claim 2
Dependent Claim
64 words
An underwater acoustic device comprising a thin spherical structure composed of polymeric piezoelectric material having a high piezoelectric stress constant and a low Young's modulus, wherein the spherical structure is gas pressurised, a film or layer of electrically conductive material on the inner end outer surfaces of the structure, and electrical terminal means contacting the film or layer on said inner and outer surfaces.
Claim 3
Dependent Claim
18 words
An underwater acoustic device according to claim 1 wherein the spherical structure is composed of polyvinylidene fluoride (pvdf).
Claim 4
Dependent Claim
38 words
An underwater acoustic device according to claim 1 or claim 2 wherein the spherical structure has an aperture and a closure member therefore wherein the closure member includes a valved inlet through which the structure may be pressurised.
Claim 5
Dependent Claim
27 words
An underwater acoustic device according to any ofthe preceding claims including attachment means for connection to a cable for downwardly suspending, or towing, the structure in water.
Claim 6
Dependent Claim
37 words
An underwater acoustic device according to any of the preceding claims wherein the electrical terminal contacting the film or layer on the inner surface is connected to a power supply line which extends through the closure member.
Claim 7
Dependent Claim
35 words
An underwater acoustic device according to any of the preceding claims wherein the spherical structure is pressurised such at the working depth there is a pressure differential across the structure wall of about 0.2 atmospheres.
Claim 8
Dependent Claim
13 words
An underwater acoustic device substantially as described herein with reference to the drawings.
Claim 9
Dependent Claim
13 words
An underwater acoustic device substantially as described herein with reference to the drawings.
References Cited (Backward Citations)
GB819644A
Cited
GB2087687A
Cited
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