Patent US2581878A successfully refreshed from Google Patents.
US2581878A
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US
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Valve mechanism for controlling flow through ion exchange apparatus
Assignee: Permutit Co
•
Filing: 1947-06-16
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Granted: 1952-01-08
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Expires: 1967-06-16
Abstract
No abstract record available.
Inventors
- 👤 Pick Eric
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:34
CPC Classifications
F; F16; F16K; F16K11/00; F16K11/02; F16K11/06; F16K11/072; F16K11/074; C; C02; C02F; C02F1/00; C02F1/42; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86863
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2364697A
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US1985449A
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US2093692A
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US2076321A
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US2254421A
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US2209993A
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US2309032A
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US2428410A
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US2422758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-01-07 | 1955-07-09 | 1956-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-01-07 | 1959-07-09 | 1960-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-01-07 | 1963-07-09 | 1964-01-08 | $7700.00 | Window Closed / Lapsed |