Patent US1923145A successfully refreshed from Google Patents.
US1923145A
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US
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Method and apparatus for heat treating
Assignee: Leeds and Northrup Co
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Filing: 1931-01-28
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Granted: 1933-08-22
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Expires: 1951-01-28
Abstract
No abstract record available.
Inventors
- 👤 John W Harsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:01
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/52; C21D9/54; C21D9/663
Claims Analysis
Total Claims: 0
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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) | 1936-08-21 | 1937-02-20 | 1937-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-08-21 | 1941-02-20 | 1941-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-08-21 | 1945-02-20 | 1945-08-22 | $7700.00 | Window Closed / Lapsed |