US3890591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grouping of electro-acoustic transducers particularly for use in underwater detection systems
Assignee: Thales SA
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Filing: 1974-02-21
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Granted: 1975-06-17
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Expires: 1994-02-21
Abstract
Abstract A grouping of electro-acoustic transducer units forming a directional array for acoustic waves multibeams reception. In the array, groups are formed with transducer units of the Langevin piezoelectric sandwich type in which at least one electrode has sectors with a flat conductive surface which form separate isolated sub-electrodes. In one embodiment a printed circuit provides said sub-electrodes and the areas of the conductive surfaces are selected to be proportional to desired weighting coefficients. The fixed beams are preformed by the way in which the separate subelectrodes associated with the various transducer units of the array are wired up.
Inventors
- 👤 Francois Bocquillon
- 👤 Roger Massiera
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:05
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0607; B06B1/0611; B06B1/0618; G; G10; G10K; G10K11/00; G10K11/18; G10K11/26; G10K11/34; G10K11/341; G10K11/346; Y; Y10; Y10S; Y10S367/00; Y10S367/905
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
90 words
A grouping of electro-acoustic transducer units into a directional array, wherein each said unit comprises: a front metal plate and a back metal plate, at least two piezoelectric wafers with two opposing parallel faces provided with electrodes forming an active part, termed the driver, stacked between said front and back metal plates of said transducer and wherein at least one of said electrodes comprises conductive areas formed by electrically insulated sectors which divide said electrode into a plurality of separate sub-electrodes located in identical cross section planes of said wafers.
Claim 2
Dependent Claim
90 words
A grouping of electro-acoustic transducer units into a directional array, wherein each said unit comprises: a front metal plate and a back metal plate, at least two piezoelectric wafers with two opposing parallel faces provided with electrodes forming an active part, termed the driver, stacked between said front and back metal plates of said transducer and wherein at least one of said electrodes comprises conductive areas formed by electrically insulated sectors which divide said electrode into a plurality of separate sub-electrodes located in identical cross section planes of said wafers.
Claim 3
Dependent Claim
48 words
A grouping according to claim 1, wherein the sector sub-electrode areas present different surface values, said values being proportional to desired amplitude-weighting coefficientS which permit, by parallel connection of given sectors, realization of surfaces with surface values proportional to other amplitude-weighting coefficients in accordance with a predetermined relationship.
Claim 4
Dependent Claim
17 words
A grouping according to claim 1, wherein the sector subelectrodes are annular in shape and are concentric.
Claim 5
Dependent Claim
32 words
A grouping according to claim 1, wherein the electrodes are formed by the conductive surfaces of printed-circuit boards associated with the opposing and un-metallised parallel faces of the wafers of piezoelectric material.
Claim 6
Dependent Claim
64 words
A grouping according to claim 2, used for receiving acoustic waves and having amplitude-weighted pre-formed reception beams, wherein the signals combination providing the beams formation is realized by connecting together selected electrode sectors associated with the different transducers used for the same beam, the amplitude weighting being accomplished by selecting sectors the areas Si of which are proportional to the desired weighting coefficients Ai.
Claim 7
Dependent Claim
40 words
A grouping according to claim 5, in which at least two of the preformed reception beams overlap, wherein said overlapping is achievied by using two separate electrode sectors simultaneously in each of the transducer units common to these two beams.
Claim 8
Dependent Claim
66 words
A grouping according to claim 5, in which the preformed and amplitude-weighted reception beams present an angle departure, wherein the electrodes associated with the transducer units employed have an even number of sectors, the areas of half of which are proportional to the coefficients A1 cos Alpha i and those of the other half of which are proportional to coefficients A1 sin Alpha i , with
Claim 9
Dependent Claim
85 words
A grouping according to claim 7, wherein the said summing unit comprises two adders each of which has one sign-changing input, the first adder supplying to one input of a third adder the sum Sigma ui Ai cos Alpha i , whereas the second adder supplies to another input of this same adder, via a ( pi /2 ) phase shifter, a value j Sigma ui Aphd i sin Alpha i , the required voltage U being obtained at the output from this third adder.
Claim 10
Dependent Claim
26 words
A grouping according to claim 3, wherein the sector sub-electrodes are annular in shape and comprise a plurality of concentric unclosed rings having individual terminal connections.
Claim 11
Dependent Claim
51 words
A grouping according to claim 4, wherein the electrodes are formed by the conductive surfaces of printed-circuit boards associated with the opposing and un-metallised parallel faces of the wafers of piezoelectric material, the sector sub-electrodes being formed by unclosed rings having terminal connections provided at the edges of said printed-circuit boards.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |