US5058339A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Curved stairway and method
Assignee: Individual
•
Filing: 1990-10-11
•
Granted: 1991-10-22
•
Expires: 2010-10-11
Abstract
Abstract A curved stairway is illustrated wherein the usual wooden components, including the stringers A, are provided with steel reinforcement, including metallic stringers B provided with cross bracing D and E in order to provide a composite structure affording rigidity with minimal reinforcement.
Inventors
- 👤 Alexander P. Krstovic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:58
CPC Classifications
E; E04; E04F; E04F11/00; E04F11/02; E04F11/104; E04F11/108; E04F11/022; E04F11/025
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
141 words
A curved stairway extending between a floor and a balcony comprising: spaced opposed upright curved wooden stringers extending vertically along and forming marginal portions of said stairway; flat metal bars forming metal stringers extending along an inside surface of said wooden stringers conforming to the curvature of said wooden stringers; a fastener securing said flat metal bar stringers to said wooden stringers causing the stringers to function as a structural unit; a plurality of first spaced structural sections extending transversely across said stairway between said metal stringers; means fixing said first structural sections to said metal stringers adjacent respective ends thereof; and a plurality of second structural sections extending between next adjacent first structural sections forming cross bracing extending between opposite corners of said first structural sections; whereby rigidity and structural integrity is imparted to said curved stairway with minimal reinforcing.
Claim 2
Dependent Claim
141 words
A curved stairway extending between a floor and a balcony comprising: spaced opposed upright curved wooden stringers extending vertically along and forming marginal portions of said stairway; flat metal bars forming metal stringers extending along an inside surface of said wooden stringers conforming to the curvature of said wooden stringers; a fastener securing said flat metal bar stringers to said wooden stringers causing the stringers to function as a structural unit; a plurality of first spaced structural sections extending transversely across said stairway between said metal stringers; means fixing said first structural sections to said metal stringers adjacent respective ends thereof; and a plurality of second structural sections extending between next adjacent first structural sections forming cross bracing extending between opposite corners of said first structural sections; whereby rigidity and structural integrity is imparted to said curved stairway with minimal reinforcing.
Claim 3
Dependent Claim
22 words
The structure set forth in claim 1 wherein said first structural sections are channel members and said second structural sections are angles.
Claim 4
Dependent Claim
33 words
The structure set forth in claim 1 wherein said fastener includes a plurality of spaced screws, and wherein respective ends of said first and second structural sections are welded to said metal stringers.
References Cited (Backward Citations)
US983213A
Cited
FR557883A
Cited
AT162250B
Cited
GB617432A
Cited
DE818687C
Cited
US3616585A
Cited
US3902948A
Cited
US4135508A
Cited
US4143740A
Cited
US4527366A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-10-21 | 1995-04-22 | 1995-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-21 | 1999-04-22 | 1999-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-21 | 2003-04-22 | 2003-10-22 | $7700.00 | Window Closed / Lapsed |