US843563A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of toughening or annealing steel, iron, and other metals.
Assignee: Individual
•
Filing: 1902-02-24
•
Granted: 1907-02-05
•
Expires: 1922-02-24
Abstract
No abstract record available.
Inventors
- 👤 William F L Frith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:39
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/34; C21D1/40; Y; Y10; Y10S; Y10S425/00; Y10S425/131
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) | 1910-02-04 | 1910-08-06 | 1911-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1914-02-04 | 1914-08-06 | 1915-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1918-02-04 | 1918-08-06 | 1919-02-05 | $7700.00 | Window Closed / Lapsed |