Patent US3633708A successfully refreshed from Google Patents.
US3633708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible ladder
Assignee: Sidewinder International Ltd
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Filing: 1970-10-12
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Granted: 1972-01-11
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Expires: 1990-10-12
Abstract
Abstract A ladder for use such as in painting spherical structures permitting facilitated movement of the ladder about the structures for facilitated work on the structures such as painting thereof. The ladder includes wheel means for permitting facilitated movement thereof about the structures and includes flexible side members to provide for accommodation of the ladder to the spherical configuration.
Inventors
- 👤 Jens A Heilskov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:16
CPC Classifications
E; E06; E06C; E06C1/00; E06C1/52; E06C1/56
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
156 words
In an apparatus for supporting workmen for working on a ball having a topside ball surface, an underside ball surface, an apical support at the top of said topside ball surface, and a stem supporting the ball above the ground, structure comprising: a flexible ladder having flexible side elements, a plurality of rigid rungs, a plurality of wheels, and securing means for fixedly retaining the rungs at preselected intervals on said side elements and for rotatably mounting the wheels on said side elements at preselected intervals for rotation about the axis of said side elements; and means for movably connecting a top end of the ladder to a support whereby said ladder may be manually moved circumferentially on the topside ball surface and spacing the rungs away from the topside ball surface sufficiently to define a toe space for a workman''s foot resting on the rung and extending from the run toward the topside ball surface.
Claim 2
Dependent Claim
156 words
In an apparatus for supporting workmen for working on a ball having a topside ball surface, an underside ball surface, an apical support at the top of said topside ball surface, and a stem supporting the ball above the ground, structure comprising: a flexible ladder having flexible side elements, a plurality of rigid rungs, a plurality of wheels, and securing means for fixedly retaining the rungs at preselected intervals on said side elements and for rotatably mounting the wheels on said side elements at preselected intervals for rotation about the axis of said side elements; and means for movably connecting a top end of the ladder to a support whereby said ladder may be manually moved circumferentially on the topside ball surface and spacing the rungs away from the topside ball surface sufficiently to define a toe space for a workman''s foot resting on the rung and extending from the run toward the topside ball surface.
Claim 3
Dependent Claim
31 words
The supporting apparatus of claim 1 wherein said securing means comprises means for mounting a pair of said wheels on the side elements closely adjacent the opposite ends of a rung.
Claim 4
Dependent Claim
28 words
The supporting apparatus of claim 1 wherein the securing means cooperatively retain a wheel and one end of a rung in fixed position longitudinally of a side element.
Claim 5
Dependent Claim
19 words
The supporting apparatus of claim 1 wherein said wheels are mounted on said side elements in laterally aligned pairs.
Claim 6
Dependent Claim
40 words
The supporting apparatus of claim 1 wherein said wheels are mounted on said side elements in laterally aligned pairs and at intervals longitudinally of said side elements at least twice as great as the preselected intervals between the rungs thereon.
Claim 7
Dependent Claim
18 words
The supporting apparatus of claim 1 wherein said wheels are provided with tires for engaging the ball surface.
Claim 8
Dependent Claim
27 words
The supporting apparatus of claim 1 wherein said ladder has a length preselected to dispose a lower portion thereof at the level of an underside ball surface.
Claim 9
Dependent Claim
19 words
The supporting apparatus of claim 1 wherein said connecting means has a length of less than approximately 4 feet.
Claim 10
Dependent Claim
27 words
The supporting apparatus of claim 1 further including a cage and means carried by the ladder for supporting the cage below the lower end of the ladder.
Claim 11
Dependent Claim
56 words
The supporting apparatus of claim 9 wherein said means for supporting the cage comprises a cable lying against the rungs and having means for connecting a top end of the cable to the support on the topside ball surface and having a lower portion extending to below the bottom of the ladder for supporting the cage.
Claim 12
Dependent Claim
48 words
A ladder construction comprising: a rung having an aperture; a flexible cable extending through said aperture; a wheel rotatably mounted on said cable adjacent said rung for rotation about the longitudinal extent of said cables; and means retaining said rung and wheel against displacement axially of said cable.
Claim 13
Dependent Claim
48 words
A ladder construction comprising: a rung having an aperture; a flexible cable extending through said aperture; a wheel rotatably mounted on said cable adjacent said rung for rotation about the longitudinal extent of said cables; and means retaining said rung and wheel against displacement axially of said cable.
Claim 14
Dependent Claim
40 words
The ladder construction of claim 11 wherein said retaining means comprises a pair of sleeves secured to said cable one above the uppermost of said juxtaposed rung and wheel and one below the lowermost of said juxtaposed rung and wheel.
Claim 15
Dependent Claim
25 words
The ladder construction of claim 11 wherein said wheel is provided with an axial bearing for free rotation thereof about the axis of said cable.
Claim 16
Dependent Claim
33 words
The ladder construction of claim 11 wherein the diameter of said wheel is at least approximately 8 inches to define a toe space perpendicular to said rung of at least approximately 4 inches.
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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |