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US2820549A
Expired / Lapsed
US
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Filters
Assignee: Belke Manuf Co
•
Filing: 1955-04-18
•
Granted: 1958-01-21
•
Expires: 1975-04-18
Abstract
No abstract record available.
Inventors
- 👤 William E Belke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:27
CPC Classifications
B; B01; B01D; B01D33/00; B01D33/44; B01D33/46; B01D33/466; B01D33/06; B01D33/073; B01D2201/00; B01D2201/26; B01D2201/265
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1253162A
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GB265856A
Cited
US1856452A
Cited
GB416097A
Cited
US2035851A
Cited
US2460280A
Cited
US2655265A
Cited
US2703177A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |