US2658180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum tube voltmeter
Assignee: Phillips Petroleum Co
•
Filing: 1950-04-10
•
Granted: 1953-11-03
•
Expires: 1970-04-10
Abstract
No abstract record available.
Inventors
- 👤 Boisblanc Deslonde R De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:30
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/165; G01R19/16504; G01R19/16514
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US683831A
Cited
DE432366C
Cited
GB406360A
Cited
US2039267A
Cited
US2295410A
Cited
US2378999A
Cited
US2443864A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-11-02 | 1957-05-04 | 1957-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-11-02 | 1961-05-04 | 1961-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-11-02 | 1965-05-04 | 1965-11-03 | $7700.00 | Window Closed / Lapsed |