Patent US3843150A successfully refreshed from Google Patents.
Patent US2306909A successfully refreshed from Google Patents.
US2306909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric crystal apparatus
Assignee: AT&T Inc
•
Filing: 1939-06-09
•
Granted: 1942-12-29
•
Expires: 1959-06-09
Abstract
No abstract record available.
Inventors
- 👤 Roger A Sykes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:13
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/54; H03H9/56; H03H9/02; H03H9/02007; H03H9/02062; H03H9/0207; H03H9/02157; H03H9/05; H03H9/09; H03H9/15; H03H9/17; H03H9/19
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1945-12-28 | 1946-06-29 | 1946-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1949-12-28 | 1950-06-29 | 1950-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1953-12-28 | 1954-06-29 | 1954-12-29 | $7700.00 | Window Closed / Lapsed |