Patent US2666632A successfully refreshed from Google Patents.
US2666632A
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US
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Perlite popping furnace
Assignee: Individual
•
Filing: 1949-10-29
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Granted: 1954-01-19
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Expires: 1969-10-29
Abstract
No abstract record available.
Inventors
- 👤 Culver Perrin Curtis
- 👤 James G Kelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:08
CPC Classifications
C; C04; C04B; C04B20/00; C04B20/02; C04B20/04; C04B20/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US212508A
Cited
US1194118A
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FR412478A
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US1163650A
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US1173708A
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US2335732A
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US2334578A
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US2421902A
Cited
US2375180A
Cited
US2563024A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-01-18 | 1957-07-20 | 1958-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-01-18 | 1961-07-20 | 1962-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-01-18 | 1965-07-20 | 1966-01-19 | $7700.00 | Window Closed / Lapsed |