Patent US3283904A successfully refreshed from Google Patents.
US3283904A
Expired / Lapsed
US
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Filter element having dual porosities
Assignee: Motors Liquidation Co
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Filing: 1963-09-09
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Granted: 1966-11-08
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Expires: 1983-09-09
Abstract
No abstract record available.
Inventors
- 👤 Buckman Kenneth Ernest
- 👤 Kemp Stanley William
- 👤 Tuffnell Derrick Percival
- 👤 Cross Ronald Arthur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:45
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/14; B01D35/147; B01D27/00; B01D27/04; B01D27/06; B01D29/00; B01D29/50; B01D29/52; B01D29/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
A FILTER FOR LIQUID COMPRISING A TUBULAR SUPPORT HAVING OPENINGS THEREIN, TWO FIXED PORTIONS OF FILTER MATERIAL, ONE OF SAID PORTIONS HAVING A FINE POROSITY AND THE OTHER A LESS FINE POROSITY, SAID PORTIONS BEING IN CONTACT WITH AND COVERING AN EXTERIOR SURFACE OF SAID TUBULAR SUPPORT, A PART OF THE SAID EXTERIOR SUPPORT SURFACE CORRESPONDING WITH SAID FINE POROSITY PORTION HAVING A NUMBER OF SAID OPENINGS PER SQUARE INCH OF AREA GREATER THAN A NUMBER OF SAID OPENINGS PER SQUARE INCH OF AREA IN PART OF THE SAID EXTERIOR SUPPORT SURFACE CORRESPONDING WITH SAID LESS FINE POROSITY PORTION.
Claim 2
Dependent Claim
99 words
A FILTER FOR LIQUID COMPRISING A TUBULAR SUPPORT HAVING OPENINGS THEREIN, TWO FIXED PORTIONS OF FILTER MATERIAL, ONE OF SAID PORTIONS HAVING A FINE POROSITY AND THE OTHER A LESS FINE POROSITY, SAID PORTIONS BEING IN CONTACT WITH AND COVERING AN EXTERIOR SURFACE OF SAID TUBULAR SUPPORT, A PART OF THE SAID EXTERIOR SUPPORT SURFACE CORRESPONDING WITH SAID FINE POROSITY PORTION HAVING A NUMBER OF SAID OPENINGS PER SQUARE INCH OF AREA GREATER THAN A NUMBER OF SAID OPENINGS PER SQUARE INCH OF AREA IN PART OF THE SAID EXTERIOR SUPPORT SURFACE CORRESPONDING WITH SAID LESS FINE POROSITY PORTION.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-11-07 | 1970-05-09 | 1970-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-11-07 | 1974-05-09 | 1974-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-11-07 | 1978-05-09 | 1978-11-08 | $7700.00 | Window Closed / Lapsed |