US 5,158,151 AGranted

Bidirectionally foldable step ladder

OwnerWan-Li Changinventor

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Abstract

A step ladder which folds with respect to a width and a depth thereof. Two sets of unidirectionally foldable steps are pivotally attached between two pairs of side rails, and foldable spreaders are pivotally attached between opposing side rails. Each step has two halves, and a brace is pivotally attached to each half. A translation assembly is disposed in each side rail to which each brace is attached. A head step is disposed on a top of the ladder and is pivotal in the two directions of the step ladder. When the ladder is folded with respect to its width, the step fold upward, drawing the braces upward by means of the translation assembly. When the ladder is folded with respect to its depth, the spreaders are folded, resulting in a completely folded ladder with the steps and the braces substantially contained within the side rails. A locking assembly is disposed between the side rails for preventing the ladder from folding. A retaining assembly prevents the ladder from unfolding.

Claims10

Dependent claims

A foldable step ladder comprising:

a first pair of side rails and a second pair of side rails, said pairs of side rails in opposition;
a first set of foldable steps and a second set of foldable steps being respectively disposed in spaced relationships between said first pair and said second pair of side rails, said steps being pivotally attached to said side rails by suitable means, said steps being foldable in a single direction;
a head step being pivotally attached to tops of said side rails by suitable means, being foldable in a same direction of said steps, and being foldable in a direction perpendicular to said direction of said steps;
and
a pair of foldable spreaders each being pivotally attached between said first and said second side rails by suitable means;
whereby said step ladder is foldable with respect to a width thereof by pivoting said steps and said head step, drawing said first pair of side rails together and drawing said second pair of side rails together, and is foldable with respect to a depth thereof by pivoting said spreaders and said head step, drawing said first pair and said second pair of side rails together.

3 more elements

Dependencies are inferred from the claim text.