Fire escape – ladder – or scaffold – Unitary foldable – rigid scaffold or ladder – Collapsible ladder
Reexamination Certificate
2003-01-17
2004-08-03
Chin-Shue, Alvin (Department: 3634)
Fire escape, ladder, or scaffold
Unitary foldable, rigid scaffold or ladder
Collapsible ladder
Reexamination Certificate
active
06769515
ABSTRACT:
BACKGROUND AND SUMMARY
The present disclosure relates to a ladder, and particularly to a collapsible ladder. More particularly, the present disclosure relates to a collapsible ladder including steps mounted on a frame for movement relative to the frame.
Ladders have a frame and one or more steps that people use for elevation when reaching for objects, painting walls, or any everyday task where extra elevation would be helpful. Ladders are often foldable for ease of storage when the ladder is not being used.
According to the present disclosure, a collapsible ladder includes left and right legs and several foldable steps extending between the left and right legs. Each step includes a left step section pivotably coupled to the left leg and a right step section pivotably coupled to the right leg. In an opened position of the ladder, the left and right legs are arranged to lie in non-parallel relation to one another and the left and right step sections cooperating to form each step are “aligned” to lie in end-to-end relation to one another. Higher steps are shorter in length while lower steps are longer in length. In a closed position of the ladder, the left and right legs are arranged to lie in parallel relation to one another and the left and right step sections cooperating to form each step are “folded” to lie in side-by-side relation to one another.
The ladder further includes a step mover for moving the left and right sections of each step between the aligned, end-to-end position and the folded, side-by-side position during movement of the left and right legs from the closed position to the opened position. Thus, the steps are equidistantly spaced apart from one another when the left and right legs are arranged to lie in non-parallel (splayed) relation in the opened position. This equidistant spacing is accomplished even though the higher steps are shorter in length and the lower steps are longer in length owing to he non-parallel, splayed orientation of the right and left legs in the opened position of the ladder. When opened, the spacing between the left and right legs is wider at the bottom and narrower at the top.
In an illustrative embodiment, a collapsible auxiliary frame is pivotably coupled to the left and right legs. A linkage is coupled to the collapsible auxiliary frame and to the left and right legs to support the left and right legs (and the steps mounted thereto) in a predetermined inclined position upon lateral spreading movement of the left and right legs relative to one another to the opened position and upon pivoting movement of the left and right legs relative to the auxiliary frame.
Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the disclosure as presently perceived.
REFERENCES:
patent: 2088878 (1937-08-01), Stogner
patent: 4106590 (1978-08-01), Tarran
patent: 5685394 (1997-11-01), Simson
“Fold-Away Four-Foot Ladder” Advertisement Literature (May 28, 2002 two pages) (website http://www.hammacher.com/publish/60156.asp).
Prior Arts Photos 1-6 of Hammacher Schlemmer Item 60156.
Gibson William R.
Hillebrecht Luke
Meeker Paul K.
Barnes & Thornburg
Chin-Shue Alvin
Cosco Management Inc.
LandOfFree
Multi-fold collapsible ladder does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multi-fold collapsible ladder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multi-fold collapsible ladder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3343684