Patent US2827218A successfully refreshed from Google Patents.
Patent US3275183A successfully refreshed from Google Patents.
US3275183A
Expired / Lapsed
US
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Secondary seal
Assignee: Helmerich and Payne Inc
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Filing: 1964-02-10
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Granted: 1966-09-27
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Expires: 1984-02-10
Abstract
No abstract record available.
Inventors
- 👤 Kenneth D Challenger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:27
CPC Classifications
B; B65; B65D; B65D88/00; B65D88/34; B65D88/42; B65D88/46; Y; Y10; Y10S; Y10S277/00; Y10S277/921
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
90 words
IN COMBINATION WITH AN OPEN END CONTAINER FOR HOLDING LIQUIDS, A FLOATING ROOF THEREFOR ADAPTED TO MOVE UPWARDLY AND DOWNWARDLY IN SAID CONTAINER WITH CHANGES IN THE LIQUID LEVEL IN SAID CONTAINER, A PRIMARY SEAL HAVING A PLURALITY OF SHOES SUPPORTED BY SAID ROOF IN CONTACT WITH THE INSIDE WALL SURFACE OF SAID CONTAINER, AND A SECONDARY SEAL AFFIXED ON THE INWARDLY EXTENDING TOP EDGES OF SAID PLURALITY OF SHOES OF SAID PRIMARY SEAL AND SLIDABLY CONTACTING SAID INSIDE WALL SURFACE, SAID SECONDARY SEAL COMPRISING A FLEXIBLE ANNULAR MEMBER HAVING
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) | 1969-09-26 | 1970-03-28 | 1970-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-26 | 1974-03-28 | 1974-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-26 | 1978-03-28 | 1978-09-27 | $7700.00 | Window Closed / Lapsed |