US3891871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure release hemispherical piezoelectric type transducer
Assignee: United States Department of the Navy
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Filing: 1974-05-24
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Granted: 1975-06-24
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Expires: 1994-05-24
Abstract
Abstract A transducer including a hemispherical piezoelectric element backed by a mass of material and enclosed by a rubber boot. Oneway pressure valves are included in the structure to permit passage of oil into and from the area between the piezoelectric element and the mass to the area between the piezoelectric element and the rubber boot in order to maintain substantially constant pressure within the piezoelectric element.
Inventors
- 👤 Theodore A Henriquez
- 👤 Allan C Tims
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:07
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0607; B06B1/0622; B06B1/0637
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
57 words
A piezoelectric transducer; which comprises, a solid cylindrical backing mass, a hemispherical piezoelectric ceramic active element secured at the major diameter thereof to one end face of said backing mass, a ring of insulating material insulating said active element from said backing mass, and a layer of fiberglass bonded between said backing mass and said insulating ring.
Claim 2
Dependent Claim
57 words
A piezoelectric transducer; which comprises, a solid cylindrical backing mass, a hemispherical piezoelectric ceramic active element secured at the major diameter thereof to one end face of said backing mass, a ring of insulating material insulating said active element from said backing mass, and a layer of fiberglass bonded between said backing mass and said insulating ring.
Claim 3
Dependent Claim
45 words
A piezoelectric transducer as claimed in claim 1; which includes, a casing surrounding said backing mass, means to prevent leakage of water between said casing and said backing mass, and a hemispherical acoustic window surrounding said active element, spaced therefrom and secured to said casing.
Claim 4
Dependent Claim
67 words
A piezoelectric transducer as claimed in claim 2; which includes, an acoustical energy transmitting fluid in the area confined by said active element and between said window and said active element, means for admitting said fluid into said areas, and intake and relief valves for compensating for differences in hydrostatic pressure of the fluid confined by said active element and between said active element and said window.
Claim 5
Dependent Claim
22 words
A piezoelectric transducer as claimed in claim 3; wherein said intake and relief valves operate at a differential pressure of 12 psi.
References Cited (Backward Citations)
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US2783449A
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US2922140A
Cited
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |