Patent US4646876A successfully refreshed from Google Patents.
US4646876A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Walking ladder
Assignee: Individual
•
Filing: 1986-05-08
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Granted: 1987-03-03
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Expires: 2006-05-08
Abstract
Abstract A walking ladder is provided and consists of a spring loaded tripod suspended from a step ladder which converts the step ladder into a self moving support. A person standing on the step ladder can shift their weight from the ladder to the tripod and then back onto the ladder while always remaining on the ladder so as to reposition the ladder anywhere in the immediate area of the tripod.
Inventors
- 👤 Robert S. Grawi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:57
CPC Classifications
E; E06; E06C; E06C1/00; E06C1/02; E06C1/14; E06C1/16; E06C1/20; E06C7/00; E06C7/42; E06C7/423
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
139 words
A walking ladder comprising: (a) a step ladder having a pair of side rails, a plurality of steps and a cross brace thereon; (b) a tripod having a top platform; and (c) means for movably suspending said tripod from said step ladder in which said tripod is normally suspended above a floor with said top platform under and extending outwardly from one of said steps so that user of said walking ladder can place one foot on said step and other foot on said top platform, whereby when said user shifts weight onto said top platform said tripod will travel down to rest on said floor allowing said user to reposition said step ladder anywhere in immediate area of said tripod and when said user shifts weight back onto said step said tripod will travel up above said floor.
Claim 2
Dependent Claim
139 words
A walking ladder comprising: (a) a step ladder having a pair of side rails, a plurality of steps and a cross brace thereon; (b) a tripod having a top platform; and (c) means for movably suspending said tripod from said step ladder in which said tripod is normally suspended above a floor with said top platform under and extending outwardly from one of said steps so that user of said walking ladder can place one foot on said step and other foot on said top platform, whereby when said user shifts weight onto said top platform said tripod will travel down to rest on said floor allowing said user to reposition said step ladder anywhere in immediate area of said tripod and when said user shifts weight back onto said step said tripod will travel up above said floor.
Claim 3
Dependent Claim
107 words
A walking ladder as recited in claim 1 wherein said tripod is foldable and comprises: (a) an inverted U-shaped member forming front legs thereof; (b) a stationary horizontal inwardly bent support member extending between said front legs so as to fit under one of said lower steps of said step ladder; (c) a lock joint extending rearwardly from said top platform; (d) a foldable rear leg extending downwardly from said lock joint; and (e) a foldable horizontal support member extending between said rear leg and middle of said stationary horizontal support member so that said tripod can fold with said step ladder when storing said step ladder.
Claim 4
Dependent Claim
53 words
A walking ladder as recited in claim 2 wherein said movably suspending means includes three elastic cords, two of said cords extend between said front legs of said tripod and said side rails while said third cord extends between said rear leg of said tripod and said cross brace of said step ladder.
Claim 5
Dependent Claim
33 words
A walking ladder as recited in claim 3 wherein said lock joint, said foldable rear leg and said foldable support member of said tripod all fold upwardly when placed in a stored position.
Claim 6
Dependent Claim
33 words
A walking ladder as recited in claim 3 wherein said lock joint, said foldable rear leg and said foldable support member of said tripod all fold sidewardly when placed in a stored position.
Claim 7
Dependent Claim
39 words
A walking ladder as recited in claim 5 wherein said lock joint further comprises radial teeth and a threaded bolt with a nut so as to lock said lock joint in a useable position and in a stored position.
Claim 8
Dependent Claim
35 words
A walking ladder as recited in claim 4 wherein said each of said legs of said tripod are height adjustable so as to fit various sized step ladders and are also fitted with non-skid tips.
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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) | 1990-03-02 | 1990-09-01 | 1991-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-02 | 1994-09-01 | 1995-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-02 | 1998-09-01 | 1999-03-03 | $7700.00 | Window Closed / Lapsed |