US2820910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage regulating vibrator
Assignee: Duracell Inc USA
•
Filing: 1955-12-14
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Granted: 1958-01-21
•
Expires: 1975-12-14
Abstract
No abstract record available.
Inventors
- 👤 Robert E Barnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:04
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/54; H02M7/58; H02M7/62
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2235316A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |