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US3946833A Expired / Lapsed US ⏱️ 0.0 years remaining

Collapsible ladder suitable for use as fire escape

Assignee: Individual
•
Filing: 1973-12-13
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Granted: 1976-03-30
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Expires: 1993-12-13
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Abstract

Abstract A collapsible ladder suitable for installation on high-rise buildings and capable of modification to be architecturally unobstrusive and compatible with a variety of architectural designs is described. The ladder comprises two or more telescoping stile pair sections in which the upper stile section has an attached upper rung and the lower stile section has an attached lower rung. The intermediate rungs are slidably mounted in the telescoping stile members which are made of channel stock. In the normal position covering a window the telescoping stile pairs are retracted and the rungs are stacked one over the other adjacent to the attached upper rung. In an emergency the ladder can be released to the extended position for use from inside a window whereby it falls on pivot arms down and away from the building at a distance sufficient to permit passage of a person between the building and the ladder, the lower stile section extends, and the rungs fall into spaced position held by spacer arms between them. Release of one ladder actuates a release mechanism on the similarly mounted ladder on the floor below and so on, allowing an escape passage to a safe level or, if necessary, to the ground.

Inventors

  • 👤 Joseph F. Riehlmann

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 22:17
CPC Classifications
E; E06; E06C; E06C9/00; E06C9/06; E06C9/08; E06C9/10

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 234 words
A ladder unit for installation in a building comprising a ladder, a frame suitable for mounting in a window, and means for attaching said ladder to said frame; said ladder comprising a plurality of telescoping pairs of stile means including an upper pair of stile means having a rung attached adjacent to its upper end; a lower pair of stile means having a rung attached adjacent to its lower end; a plurality of slidable rungs slidably mounted in said stile means permitting positioning of said slidable rungs substantially adjacent to the attached rung on the upper stile means in the storage position; said slidable rungs having means to maintain the rungs in substantially equal and parallel spaced relation over the length of said ladder in extended position; in which said ladder is mounted in said frame in the storage position by arms pivotally attached to said frame and said ladder which allow movement of said ladder outwardly and downwardly to an extended position and means attached to said frame and said ladder for limiting outward and downward movement of said ladder to the extended position in which the ladder is spaced parallel from said frame by a distance sufficient to permit access by a person between said frame and said ladder; said ladder unit including means responsive to actuation from inside or outside of said frame for releasing said ladder from the storage position.
Claim 2
Dependent Claim 234 words
A ladder unit for installation in a building comprising a ladder, a frame suitable for mounting in a window, and means for attaching said ladder to said frame; said ladder comprising a plurality of telescoping pairs of stile means including an upper pair of stile means having a rung attached adjacent to its upper end; a lower pair of stile means having a rung attached adjacent to its lower end; a plurality of slidable rungs slidably mounted in said stile means permitting positioning of said slidable rungs substantially adjacent to the attached rung on the upper stile means in the storage position; said slidable rungs having means to maintain the rungs in substantially equal and parallel spaced relation over the length of said ladder in extended position; in which said ladder is mounted in said frame in the storage position by arms pivotally attached to said frame and said ladder which allow movement of said ladder outwardly and downwardly to an extended position and means attached to said frame and said ladder for limiting outward and downward movement of said ladder to the extended position in which the ladder is spaced parallel from said frame by a distance sufficient to permit access by a person between said frame and said ladder; said ladder unit including means responsive to actuation from inside or outside of said frame for releasing said ladder from the storage position.

References Cited (Backward Citations)

US278865A Cited
US905529A Cited
US1047618A Cited
US1084737A Cited
US1567447A Cited
US2529112A Cited
US3444958A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-30 1979-09-29 1980-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-30 1983-09-29 1984-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-30 1987-09-29 1988-03-30 $7700.00 Window Closed / Lapsed

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