Patent US3232378A successfully refreshed from Google Patents.
US3232378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ladder rungs
Assignee: White Metal Rolling and Stamping Corp
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Filing: 1963-12-19
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Granted: 1966-02-01
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Expires: 1983-12-19
Abstract
No abstract record available.
Inventors
- 👤 Clayton E Larson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:24
CPC Classifications
E; E06; E06C; E06C7/00; E06C7/08; E06C7/081; E06C7/082; E06C7/084; E06C7/085; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49908; Y10T29/49915; Y10T29/49922
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
171 words
ALIGHT METAL LADDER COMPRISING: A PAIR OF SIDERAILS EXTRUDED FROM THE LIGHT METAL COMPRISING A FLAT CENTRAL WEB PORTION AND A PAIR OF END FLANGE PORTIONS; A PLURALITY OF TUBULAR RUNGS EACH EXTRUDED FROM LIGHT METAL ALLOY TO HAVE; (A) PERIPHERALLY SPACED, SUBSTANTIALLY FLAT TOP, BOTTOM AND SIDE WALL PORTIONS EXTENDING LONGITUDINALLY OF THE RUNG, AND (B) FOUR INTERMEDIATE ARCUATE WALL PORTION INTEGRALLY CONNECTED TO SAID FLAT WALL PORTIONS, AND (C) FOUR TABS ON EACH END THEREOF THAT ARE STRAIGHT EXTENSIONS OF SAID FLAT WALL PORTIONS FORMED BY REMOVAL OF THE ARCUATE WALL PORTIONS FROM THEREBETWEEN TO THE DEPTH OF SAID TABS; SETS OF FOUR SLOTS THROUGH THE CENTRAL WEB PORTION OF SAID SIDERAILS ARRANGED TO CONFORM WITH THE CROSS-SECTIONAL CONFIGURATION OF THE FOUR TABS OF SAID TUBULAR RUNGS, THE SLOTS CORRESPONDING TO THE TABS CONSTITUTING STRAIGHT EXTENSIONS OF SAID TOP AND BOTTOM WALL PORTIONS OF THE RUNGS BEING DISPOSED IN SPACED RELATIONSHIP ALONG AND PERPENDICULAR TO THE LONGITUDINAL CENTERLINE OF THE SIDE RAILS; SAID RUNGS BEING SPACED SUBSTANTIALLY EQUIDISTANT ALONG
Claim 2
Dependent Claim
171 words
ALIGHT METAL LADDER COMPRISING: A PAIR OF SIDERAILS EXTRUDED FROM THE LIGHT METAL COMPRISING A FLAT CENTRAL WEB PORTION AND A PAIR OF END FLANGE PORTIONS; A PLURALITY OF TUBULAR RUNGS EACH EXTRUDED FROM LIGHT METAL ALLOY TO HAVE; (A) PERIPHERALLY SPACED, SUBSTANTIALLY FLAT TOP, BOTTOM AND SIDE WALL PORTIONS EXTENDING LONGITUDINALLY OF THE RUNG, AND (B) FOUR INTERMEDIATE ARCUATE WALL PORTION INTEGRALLY CONNECTED TO SAID FLAT WALL PORTIONS, AND (C) FOUR TABS ON EACH END THEREOF THAT ARE STRAIGHT EXTENSIONS OF SAID FLAT WALL PORTIONS FORMED BY REMOVAL OF THE ARCUATE WALL PORTIONS FROM THEREBETWEEN TO THE DEPTH OF SAID TABS; SETS OF FOUR SLOTS THROUGH THE CENTRAL WEB PORTION OF SAID SIDERAILS ARRANGED TO CONFORM WITH THE CROSS-SECTIONAL CONFIGURATION OF THE FOUR TABS OF SAID TUBULAR RUNGS, THE SLOTS CORRESPONDING TO THE TABS CONSTITUTING STRAIGHT EXTENSIONS OF SAID TOP AND BOTTOM WALL PORTIONS OF THE RUNGS BEING DISPOSED IN SPACED RELATIONSHIP ALONG AND PERPENDICULAR TO THE LONGITUDINAL CENTERLINE OF THE SIDE RAILS; SAID RUNGS BEING SPACED SUBSTANTIALLY EQUIDISTANT ALONG
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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) | 1969-01-31 | 1969-08-02 | 1970-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-01-31 | 1973-08-02 | 1974-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-01-31 | 1977-08-02 | 1978-02-01 | $7700.00 | Window Closed / Lapsed |