Patent US2193770A successfully refreshed from Google Patents.
US2193770A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for spot-hardening
Assignee: Thomas & Skinner Steel Product
•
Filing: 1938-07-05
•
Granted: 1940-03-12
•
Expires: 1958-07-05
Abstract
No abstract record available.
Inventors
- 👤 Earl R Piercy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:30
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/34; C21D1/40
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) | 1943-03-12 | 1943-09-11 | 1944-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-03-12 | 1947-09-11 | 1948-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-03-12 | 1951-09-11 | 1952-03-12 | $7700.00 | Window Closed / Lapsed |