Patent US3339791A successfully refreshed from Google Patents.
US3339791A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Emergency venting manhole cover
Assignee: Individual
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Filing: 1965-10-22
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Granted: 1967-09-05
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Expires: 1985-10-22
Abstract
No abstract record available.
Inventors
- 👤 Frees Joseph H De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:37
CPC Classifications
F; F16; F16J; F16J13/00; F16J13/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
116 words
A MANHOLE COVER FOR A LIQUID CONTAINER COMPRISING (A) A SEAT WHICH DEFINEES AND EXTENDS COMPLETELY AROUND AN OPENING INTO SAID CONTAINER, (B) A COVER WHICH CLOSES SAID OPENING AND IS POSITIONED TO MOVE INTO AND OUT OF ENGAGEMENT WITH SAID SEAT, (C) A LOCK ARM WITH A PIVOT MOUNTING UPON SAID CONTAINER ADJACENT SAID SEAT AND DISPOSED TO EXTEND OVER SAID OPENING AND SAID COVER AND BEING SPACED APART FROM SAID COVER, (D) SAID LOCK ARM INCLUDING A FIRST SPRING MOUNTING WHICH EXTENDS TOWARDS SAID COVER, (E) SAID COVER INCLUDING A SECOND SPRING MOUNTING SUBSTANTIALLY IN ALIGNMENT WITH AND SPACED APART FROM SAID FIRST SPRING SEAT, (F) SPRING MEANS DISPOSED UPON SAID TWO SPRING MOUNTINGS,
Claim 2
Dependent Claim
116 words
A MANHOLE COVER FOR A LIQUID CONTAINER COMPRISING (A) A SEAT WHICH DEFINEES AND EXTENDS COMPLETELY AROUND AN OPENING INTO SAID CONTAINER, (B) A COVER WHICH CLOSES SAID OPENING AND IS POSITIONED TO MOVE INTO AND OUT OF ENGAGEMENT WITH SAID SEAT, (C) A LOCK ARM WITH A PIVOT MOUNTING UPON SAID CONTAINER ADJACENT SAID SEAT AND DISPOSED TO EXTEND OVER SAID OPENING AND SAID COVER AND BEING SPACED APART FROM SAID COVER, (D) SAID LOCK ARM INCLUDING A FIRST SPRING MOUNTING WHICH EXTENDS TOWARDS SAID COVER, (E) SAID COVER INCLUDING A SECOND SPRING MOUNTING SUBSTANTIALLY IN ALIGNMENT WITH AND SPACED APART FROM SAID FIRST SPRING SEAT, (F) SPRING MEANS DISPOSED UPON SAID TWO SPRING MOUNTINGS,
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) | 1970-09-04 | 1971-03-06 | 1971-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-09-04 | 1975-03-06 | 1975-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-09-04 | 1979-03-06 | 1979-09-05 | $7700.00 | Window Closed / Lapsed |