Patent US4581428A successfully refreshed from Google Patents.
US2334652A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and preparation for heat treating of steel
Assignee: EDNA I BEEKMAN
•
Filing: 1941-04-22
•
Granted: 1943-11-16
•
Expires: 1961-04-22
Abstract
No abstract record available.
Inventors
- 👤 Joseph H Schmitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:46
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/20; C23C8/22; C21; C21D; C21D1/00; C21D1/74; C21D1/76
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) | 1946-11-15 | 1947-05-17 | 1947-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1950-11-15 | 1951-05-17 | 1951-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1954-11-15 | 1955-05-17 | 1955-11-16 | $7700.00 | Window Closed / Lapsed |