US3142356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ladder construction
Assignee: Howard B Rich Inc
•
Filing: 1963-08-02
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Granted: 1964-07-28
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Expires: 1983-08-02
Abstract
No abstract record available.
Inventors
- 👤 Howard B Rich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:39
CPC Classifications
E; E06; E06C; E06C7/00; E06C7/08; E06C7/082; E06C7/088
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
145 words
A LADDER WHICH COMPRISES A PAIR OF ELONGATED SPACED RAILS, A PLURALITY OF TUBULAR RUNGS SPANNING THE RAILS, THE RAILS HAVING ANNULAR SOCKETS OF SUBSTANTIAL DEPTH ON THEIR INSIDE FACES, EACH ANNULAR SOCKET HAVING A PLUG IN FIXED RELATION TO THE RAIL AND COAXIAL WITH THE SOCKET, END PORTIONS OF THE RUNGS BEING RECEIVED IN SAID ANNULAR SOCKETS, THERE BEING OUTWARDLY EXTENDING RETURN BENT FLANGES ON EACH RUNG ENGAGING INNER FACES OF THE RAILS, THERE BEING RIBS EXTENDING LENGTHWISE OF THE RUNGS, THE ENDS OF THE RUNGS WHEN RECEIVED IN SUCH SOCKETS BEING SUBSTANTIALLY FILLED BY SAID PLUGS AND MEANS FOR DRAWING THE RAILS TOWARD EACH OTHER TO CAUSE THE RAILS TO ENGAGE THE RETURN BENT FLANGES TO BRACE THE LADDER AGAINST RACK AND LIMIT ADVANCE OF ENDS OF THE RUNGS INTO SAID SOCKETS AND FRICTIONALLY LOCK THE RUNGS AGAINST TURNING RELATIVE TO THE RAILS.
Claim 2
Dependent Claim
145 words
A LADDER WHICH COMPRISES A PAIR OF ELONGATED SPACED RAILS, A PLURALITY OF TUBULAR RUNGS SPANNING THE RAILS, THE RAILS HAVING ANNULAR SOCKETS OF SUBSTANTIAL DEPTH ON THEIR INSIDE FACES, EACH ANNULAR SOCKET HAVING A PLUG IN FIXED RELATION TO THE RAIL AND COAXIAL WITH THE SOCKET, END PORTIONS OF THE RUNGS BEING RECEIVED IN SAID ANNULAR SOCKETS, THERE BEING OUTWARDLY EXTENDING RETURN BENT FLANGES ON EACH RUNG ENGAGING INNER FACES OF THE RAILS, THERE BEING RIBS EXTENDING LENGTHWISE OF THE RUNGS, THE ENDS OF THE RUNGS WHEN RECEIVED IN SUCH SOCKETS BEING SUBSTANTIALLY FILLED BY SAID PLUGS AND MEANS FOR DRAWING THE RAILS TOWARD EACH OTHER TO CAUSE THE RAILS TO ENGAGE THE RETURN BENT FLANGES TO BRACE THE LADDER AGAINST RACK AND LIMIT ADVANCE OF ENDS OF THE RUNGS INTO SAID SOCKETS AND FRICTIONALLY LOCK THE RUNGS AGAINST TURNING RELATIVE TO THE RAILS.
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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) | 1967-07-28 | 1968-01-27 | 1968-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-07-28 | 1972-01-27 | 1972-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-07-28 | 1976-01-27 | 1976-07-28 | $7700.00 | Window Closed / Lapsed |