Nested Stepladder Assemblies for Compact Collapsed Volume

Solution Overview

Problem

Conventional stepladders are bulky in their collapsed state, making them difficult to carry and store, and increasing shipping and storage costs due to their large volume.

Innovation Solution

A stepladder design featuring a first assembly and a second assembly that are pivotally coupled, allowing the stepladder to be selectively positioned between a deployed and a collapsed state, with the second assembly being nested within the first assembly's volume, reducing the overall depth and volume when collapsed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If conventional stepladder configurations are used, then the ladder provides stable support and structural strength, but the ladder occupies large volume when collapsed

Engineering Contradiction:

Improvevolume when collapsedVSAvoidstructural strength

Core Design Contradiction:

Volume of moving objectVSStrength

Solution Approach 1:

The patent applies nesting by positioning the second assembly within the envelope defined by the first assembly when collapsed. The rails of the second assembly are received within the space occupied by the first assembly, allowing one structural component to be nested inside another, significantly reducing the overall volume of the collapsed ladder while preserving the integrity of both assemblies.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent reconfigures the spatial arrangement of ladder assemblies by transitioning from a side-by-side configuration to a nested configuration. This dimensional reorganization allows the second assembly to be positioned within the three-dimensional envelope of the first assembly, reducing the collapsed volume from a rectangular prism defined by combined depths to a more compact configuration where volumes overlap.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Ease of operation

If conventional stepladder configurations are used, then the ladder provides stable support, but it is difficult to carry and store

Engineering Contradiction:

Improveease of carrying and storingVSAvoidvolume when collapsed

Core Design Contradiction:

Ease of operationVSVolume of moving object

Solution Approach 1:

The patent applies nesting by positioning the second assembly within the envelope defined by the first assembly when collapsed. The rails of the second assembly are received within the space occupied by the first assembly, allowing one structural component to be nested inside another, significantly reducing the overall volume of the collapsed ladder while preserving the integrity of both assemblies.

Inventive Principle:

Principle #7Nested doll (Nesting)

3Strength

If conventional stepladder configurations are used, then the ladder maintains structural integrity, but shipping costs increase

Engineering Contradiction:

Improvestructural integrityVSAvoidshipping volume

Core Design Contradiction:

StrengthVSVolume of stationary object

Solution Approach 1:

The patent applies nesting by positioning the second assembly within the envelope defined by the first assembly when collapsed. The rails of the second assembly are received within the space occupied by the first assembly, allowing one structural component to be nested inside another, significantly reducing the overall volume of the collapsed ladder while preserving the integrity of both assemblies.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent merges the spatial occupation of the two assemblies by positioning them to overlap in space when collapsed. Instead of occupying separate volumes, the assemblies are configured so that the second assembly occupies space within the envelope of the first assembly, effectively combining their spatial footprints into a single reduced volume for shipping purposes.

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS9920572B2Stepladders and related methods

Publication Date: 2018.03.20 LITTLE GIANT LADDER SYSTEMS LLC

AI summary

Stepladders and related methods of using and manufacturing stepladders are provided. In one embodiment, a stepladder is provided that comprises a top cap, a first assembly and a second assembly. The first assembly has a pair of spaced apart rails pivotally coupled with the top cap. The second assembly includes at least one rail pivotally coupled with the top cap. The first assembly and second assembly are configured to be displaced relative one another such that the stepladder is selectively positionable between a first, deployed state and a second, collapsed state. The first assembly, the second assembly and the top cap are cooperatively configured such that the at least one rail of the second assembly is at least partially nested within an envelope defined by the pair of spaced apart rails of the first assembly with the step ladder is in a collapsed state.