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US2589811A
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US
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Gas atmosphere generating means for heat-treating furnaces
Assignee: Holcroft and Co
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Filing: 1948-04-05
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Granted: 1952-03-18
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Expires: 1968-04-05
Abstract
No abstract record available.
Inventors
- 👤 Walter H Holcroft
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:25
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/74; C21D1/76; C21D1/763; C21D9/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-03-18 | 1955-09-17 | 1956-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-03-18 | 1959-09-17 | 1960-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-03-18 | 1963-09-17 | 1964-03-18 | $7700.00 | Window Closed / Lapsed |