US4578611A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric stress wave transducer with boron nitride piezo support
Assignee: Rolls Royce PLC
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Filing: 1985-01-22
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Granted: 1986-03-25
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Expires: 2005-01-22
Abstract
Abstract A transducer for detecting stress waves comprises a piezo-electric member which is mounted on a brass backing member and carried by a boron nitride support member. The piezo-electric member is deformed under the influence of stress waves to generate an electrical output, the magnitude of which is indicative of the magnitude of the stress waves.
Inventors
- 👤 Michael Sadler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:27
CPC Classifications
G; G01; G01H; G01H11/00; G01H11/06; G01H11/08
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
88 words
A transducer for detecting stress waves comprising a piezo-electric member, an electrically conductive backing member upon which said piezo-electric member is mounted and which is in electrical contact therewith and a boron nitride support member which carries both said piezo-electric member and said backing member, said piezo-electric member being so disposed as to be operationally exposed to stress waves whereby any such stress waves cause said piezo-electric to deform and thereby generate an electrical output, the magnitude of which is indicative of the magnitude of said stress waves.
Claim 2
Dependent Claim
88 words
A transducer for detecting stress waves comprising a piezo-electric member, an electrically conductive backing member upon which said piezo-electric member is mounted and which is in electrical contact therewith and a boron nitride support member which carries both said piezo-electric member and said backing member, said piezo-electric member being so disposed as to be operationally exposed to stress waves whereby any such stress waves cause said piezo-electric to deform and thereby generate an electrical output, the magnitude of which is indicative of the magnitude of said stress waves.
Claim 3
Dependent Claim
44 words
A transducer as claimed in claim 1 wherein said transducer is provided with a protective barrier which barrier is interposed between said piezo-electric member and the source of said any such stress waves, said barrier being substantially transparent to said any such stress waves.
Claim 4
Dependent Claim
20 words
A transducer as claimed in claim 2 wherein said protective barrier comprises a silica element provided with a metallic coating.
Claim 5
Dependent Claim
16 words
A transducer as claimed in claim 3 wherein said protective barrier additionally comprises a metallic diaphragm.
Claim 6
Dependent Claim
55 words
A transducer as claimed in claim 3 wherein said piezo-electric member and said metal coated silica element are disc-shaped, and said boron nitride support member is generally in the shape of a hollow cylinder, said piezo-electric member and said metal coated silicon element being enclosed within said boron nitride support member in coaxial relationship therewith.
Claim 7
Dependent Claim
21 words
A transducer as claimed in claim 1 wherein said piezo-electric member is in the form of a lead zirconate titanate crystal.
Claim 8
Dependent Claim
17 words
A transducer as claimed in claim 1 wherein said electrically conductive backing member is made from brass.
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) | 1989-03-24 | 1989-09-23 | 1990-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-24 | 1993-09-23 | 1994-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-24 | 1997-09-23 | 1998-03-25 | $7700.00 | Window Closed / Lapsed |