Retractable Stair Assembly Interior Cavity Protection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing retractable stair assemblies for trailers are vulnerable to damage and exposure to elements due to their installation underneath the vehicle, requiring a lift mechanism that increases complexity and manufacturing cost, and lacks adjustable step platform length.

Innovation Solution

A retractable stair assembly installed within the interior cavity of the trailer frame, protected from elements, with a slide assembly allowing linear movement between stowed and deployed positions without a lift mechanism, enabling adjustable step platform length and reduced vulnerability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the retractable stair assembly is installed underneath the trailer, then it provides a transitional surface when deployed, but it is exposed to the elements and vulnerable to damage

Engineering Contradiction:

Improveprotection from elements and damageVSAvoidexposure to rain, snow, road salt, dirt, and physical damage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The stair assembly is extracted from its conventional position underneath the trailer and relocated to a protected interior cavity within the trailer frame. This extraction removes the harmful environmental factors from the stair assembly's exposure while maintaining its functional capability when deployed.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The design transitions from a single-plane deployment to a multi-dimensional solution where the stair assembly moves between storage in the interior cavity and deployment to an exterior position, utilizing vertical and horizontal space to achieve both protection and functionality.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Ease of operation

If a lift mechanism is used to elevate the step platform during deployment, then the first step is positioned at a safe height, but the complexity and manufacturing cost increase

Engineering Contradiction:

Improvesafe transition heightVSAvoidlift mechanism complexity and manufacturing cost

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The design eliminates the need for active elevation by positioning the stair assembly in the interior cavity at an appropriate height, allowing the steps to extend outward to the required elevation without requiring additional lift mechanisms. The gravitational potential is optimized to provide safe step height naturally.

Inventive Principle:

Principle #12Equipotentiality

Solution Approach 2:

Instead of using a mechanism to actively lift the platform upward during deployment, the design inverts the approach by pre-positioning the platform in the interior cavity at the correct elevation, allowing gravity to assist rather than resist the deployment motion.

Inventive Principle:

Principle #13The other way round (Inversion)

3Adaptability or versatility

If the step platform has a fixed length, then the lift mechanism can maintain proper elevation, but the platform length cannot be adjusted for different configurations

Engineering Contradiction:

Improveadjustable step platform lengthVSAvoidfixed length requirement for lift mechanism operation

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The step platform transitions from a fixed-length design to an adjustable-length configuration. The platform can be extended or retracted to different lengths while maintaining proper elevation, providing adaptability for various deployment scenarios without requiring complex active lift mechanisms.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The step platform is designed to serve multiple functions: it can be adjusted to different lengths for various configurations, stored compactly in the interior cavity, and deployed to provide safe elevation. This multi-functionality eliminates the need for separate adjustment mechanisms while maintaining versatility.

Inventive Principle:

Principle #6Universality (Multi-functionality)

4Length of moving object

If the retractable stair assembly is placed underneath the trailer frame, then it can be stowed out of the way, but it reduces clearance underneath the trailer on steep slopes

Engineering Contradiction:

Improveclearance underneath trailerVSAvoidspace occupied by stair assembly

Core Design Contradiction:

Length of moving objectVSArea of stationary object

Solution Approach 1:

The stair assembly is nested within the interior cavity of the trailer frame, utilizing the available internal space for storage. This nesting approach eliminates the need for external storage space underneath the trailer, preserving clearance and preventing interference with ground contact on steep slopes.

Inventive Principle:

Principle #7Nested doll (Nesting)

Data Source

PatentUS11731562B2Trailer step assembly

Publication Date: 2023.08.22 HONER KURT JOSEF

AI summary

A trailer, retractable stair assembly, and method of operating same is provided. The trailer includes a frame that defines an interior cavity. A retractable stair assembly is movable between a stowed position in which the retractable stair assembly is positioned within the interior cavity and a deployed position in which the retractable stair assembly extends out of the trailer frame to establish a plurality of steps out of the trailer to an egress surface.