Patent US2820263A successfully refreshed from Google Patents.
US2820263A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for ultrasonic treatment of molten metal
Assignee: Individual
•
Filing: 1955-05-13
•
Granted: 1958-01-21
•
Expires: 1975-05-13
Abstract
No abstract record available.
Inventors
- 👤 Fruengel Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:33
CPC Classifications
B; B22; B22D; B22D1/00; B01; B01J; B01J19/00; B01J19/08; B01J19/10; B22D27/00; B22D27/08
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1318740A
Cited
US726515A
Cited
US1689196A
Cited
US1939712A
Cited
GB456657A
Cited
GB480554A
Cited
US2419373A
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 |