Patent US2538554A successfully refreshed from Google Patents.
US2538554A
Expired / Lapsed
US
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Process of producing piezoelectric transducers
Assignee: Zenith Electronics LLC
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Filing: 1947-08-22
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Granted: 1951-01-16
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Expires: 1967-08-22
Abstract
No abstract record available.
Inventors
- 👤 Jr Walter L Cherry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:16
CPC Classifications
H; H01; H01G; H01G7/00; H01G7/02; H10; H10N; H10N30/00; H10N30/01; H10N30/04; H10N30/045; H10N30/80; H10N30/85; H10N30/853; H10N30/8536; Y; Y10; Y10T; Y10T29/00; Y10T29/42; Y10T29/43; Y10T29/435
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
THE PROCESS OF PRODUCING A PERMANENT PIEZOELECTRIC EFFECT IN A SOLID POLYCRYSTALLINE AGGREGATE OF CRYSTALS INDIVIDUALLY POSSESSING PIEZO-ELECTRIC PROPERTIES BELOW A PREDETERMINED TRANSITION TEMPERATURE AND LOSING SAID PROPERTIES ABOVE SAID TRANSITION TEMPERATURE, WHICH PROCESS COMPRISES: MAINTAINING SAID AGGREGATED AT A TEMPERATURE BELOW SAID TRANSITION TEMPERATURE; PRODUCING A UNI DIRECTIONAL ELECTROSTATIC POLARIZING FIELD IN SAID AGGREGATE; AND MAINTAINING SAID POLARIZING FIELD FOR A SUBSTANTIAL TIME AT LEAST APPROACHING THAT REQUIRED FOR SATURATION OF SAID EFFECT.
Claim 2
Dependent Claim
74 words
THE PROCESS OF PRODUCING A PERMANENT PIEZOELECTRIC EFFECT IN A SOLID POLYCRYSTALLINE AGGREGATE OF CRYSTALS INDIVIDUALLY POSSESSING PIEZO-ELECTRIC PROPERTIES BELOW A PREDETERMINED TRANSITION TEMPERATURE AND LOSING SAID PROPERTIES ABOVE SAID TRANSITION TEMPERATURE, WHICH PROCESS COMPRISES: MAINTAINING SAID AGGREGATED AT A TEMPERATURE BELOW SAID TRANSITION TEMPERATURE; PRODUCING A UNI DIRECTIONAL ELECTROSTATIC POLARIZING FIELD IN SAID AGGREGATE; AND MAINTAINING SAID POLARIZING FIELD FOR A SUBSTANTIAL TIME AT LEAST APPROACHING THAT REQUIRED FOR SATURATION OF SAID EFFECT.
References Cited (Backward Citations)
GB302726A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-15 | 1954-07-17 | 1955-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-15 | 1958-07-17 | 1959-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-15 | 1962-07-17 | 1963-01-16 | $7700.00 | Window Closed / Lapsed |