US2939316A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High vacuum device
Assignee: National Research Corp
•
Filing: 1958-03-14
•
Granted: 1960-06-07
•
Expires: 1978-03-14
Abstract
No abstract record available.
Inventors
- 👤 Beecher Norman
- 👤 Jr Milo P Hnilicka
- 👤 Paul W Patton
- 👤 Arthur G Walsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:01
CPC Classifications
F; F02; F02K; F02K9/00; F02K9/96
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
FR1002071A
Cited
US2615331A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-07 | 1963-12-07 | 1964-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-07 | 1967-12-07 | 1968-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-07 | 1971-12-07 | 1972-06-07 | $7700.00 | Window Closed / Lapsed |